librustc: Make vectors no longer implicitly copyable in rustc. r=graydon

~20% perf win for trans on -O0, with other minor improvements across the board.
No effect on -O2.

100 files changed, 1216 insertions, 867 deletions

diff --git a/src/librustc/back/link.rs b/src/librustc/back/link.rs
index a2b67e8380b..17222b7498b 100644
--- a/src/librustc/back/link.rs
+++ b/src/librustc/back/link.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::rpath;
 use driver::session;
 use lib::llvm::llvm;
@@ -56,11 +57,13 @@ impl output_type : cmp::Eq {
     pure fn ne(&self, other: &output_type) -> bool { !(*self).eq(other) }
 }
 
-fn llvm_err(sess: Session, msg: ~str) -> ! unsafe {
+fn llvm_err(sess: Session, +msg: ~str) -> ! unsafe {
     let cstr = llvm::LLVMRustGetLastError();
     if cstr == ptr::null() {
         sess.fatal(msg);
-    } else { sess.fatal(msg + ~": " + str::raw::from_c_str(cstr)); }
+    } else {
+        sess.fatal(msg + ~": " + str::raw::from_c_str(cstr));
+    }
 }
 
 fn WriteOutputFile(sess: Session,
@@ -147,7 +150,7 @@ pub mod jit {
             };
             let func: fn(++argv: ~[~str]) = cast::transmute(move closure);
 
-            func(~[sess.opts.binary]);
+            func(~[/*bad*/copy sess.opts.binary]);
         }
     }
 }
@@ -177,7 +180,7 @@ mod write {
         if sess.time_llvm_passes() { llvm::LLVMRustEnableTimePasses(); }
         let mut pm = mk_pass_manager();
         let td = mk_target_data(
-            sess.targ_cfg.target_strs.data_layout);
+            /*bad*/copy sess.targ_cfg.target_strs.data_layout);
         llvm::LLVMAddTargetData(td.lltd, pm.llpm);
         // FIXME (#2812): run the linter here also, once there are llvm-c
         // bindings for it.
@@ -438,17 +441,19 @@ fn build_link_meta(sess: Session, c: ast::crate, output: &Path,
         let mut name: Option<~str> = None;
         let mut vers: Option<~str> = None;
         let mut cmh_items: ~[@ast::meta_item] = ~[];
-        let linkage_metas = attr::find_linkage_metas(c.node.attrs);
-        attr::require_unique_names(sess.diagnostic(), linkage_metas);
+        let linkage_metas =
+            attr::find_linkage_metas(/*bad*/copy c.node.attrs);
+        // XXX: Bad copy.
+        attr::require_unique_names(sess.diagnostic(), copy linkage_metas);
         for linkage_metas.each |meta| {
             if attr::get_meta_item_name(*meta) == ~"name" {
                 match attr::get_meta_item_value_str(*meta) {
-                  Some(ref v) => { name = Some((*v)); }
+                  Some(ref v) => { name = Some((/*bad*/copy *v)); }
                   None => cmh_items.push(*meta)
                 }
             } else if attr::get_meta_item_name(*meta) == ~"vers" {
                 match attr::get_meta_item_value_str(*meta) {
-                  Some(ref v) => { vers = Some((*v)); }
+                  Some(ref v) => { vers = Some((/*bad*/copy *v)); }
                   None => cmh_items.push(*meta)
                 }
             } else { cmh_items.push(*meta); }
@@ -469,7 +474,7 @@ fn build_link_meta(sess: Session, c: ast::crate, output: &Path,
             return len_and_str(pprust::lit_to_str(@l));
         }
 
-        let cmh_items = attr::sort_meta_items(metas.cmh_items);
+        let cmh_items = attr::sort_meta_items(/*bad*/copy metas.cmh_items);
 
         symbol_hasher.reset();
         for cmh_items.each |m| {
@@ -504,15 +509,16 @@ fn build_link_meta(sess: Session, c: ast::crate, output: &Path,
     fn crate_meta_name(sess: Session, _crate: ast::crate,
                        output: &Path, metas: provided_metas) -> ~str {
         return match metas.name {
-              Some(ref v) => (*v),
+              Some(ref v) => (/*bad*/copy *v),
               None => {
                 let name = match output.filestem() {
                   None => sess.fatal(fmt!("output file name `%s` doesn't\
                                            appear to have a stem",
                                           output.to_str())),
-                  Some(ref s) => (*s)
+                  Some(ref s) => (/*bad*/copy *s)
                 };
-                warn_missing(sess, ~"name", name);
+                // XXX: Bad copy.
+                warn_missing(sess, ~"name", copy name);
                 name
               }
             };
@@ -521,10 +527,11 @@ fn build_link_meta(sess: Session, c: ast::crate, output: &Path,
     fn crate_meta_vers(sess: Session, _crate: ast::crate,
                        metas: provided_metas) -> ~str {
         return match metas.vers {
-              Some(ref v) => (*v),
+              Some(ref v) => (/*bad*/copy *v),
               None => {
                 let vers = ~"0.0";
-                warn_missing(sess, ~"vers", vers);
+                // Bad copy.
+                warn_missing(sess, ~"vers", copy vers);
                 vers
               }
             };
@@ -565,10 +572,11 @@ fn symbol_hash(tcx: ty::ctxt, symbol_hasher: &hash::State, t: ty::t,
 
 fn get_symbol_hash(ccx: @crate_ctxt, t: ty::t) -> ~str {
     match ccx.type_hashcodes.find(t) {
-      Some(ref h) => return (*h),
+      Some(ref h) => return (/*bad*/copy *h),
       None => {
         let hash = symbol_hash(ccx.tcx, ccx.symbol_hasher, t, ccx.link_meta);
-        ccx.type_hashcodes.insert(t, hash);
+        // XXX: Bad copy. Prefer `@str`?
+        ccx.type_hashcodes.insert(t, copy hash);
         return hash;
       }
     }
@@ -625,21 +633,26 @@ fn mangle(sess: Session, ss: path) -> ~str {
     n
 }
 
-fn exported_name(sess: Session, path: path, hash: ~str, vers: ~str) -> ~str {
+fn exported_name(sess: Session,
+                 +path: path,
+                 +hash: ~str,
+                 +vers: ~str) -> ~str {
     return mangle(sess,
                   vec::append_one(
                       vec::append_one(path, path_name(sess.ident_of(hash))),
                       path_name(sess.ident_of(vers))));
 }
 
-fn mangle_exported_name(ccx: @crate_ctxt, path: path, t: ty::t) -> ~str {
+fn mangle_exported_name(ccx: @crate_ctxt, +path: path, t: ty::t) -> ~str {
     let hash = get_symbol_hash(ccx, t);
-    return exported_name(ccx.sess, path, hash, ccx.link_meta.vers);
+    return exported_name(ccx.sess, path,
+                         hash,
+                         /*bad*/copy ccx.link_meta.vers);
 }
 
 fn mangle_internal_name_by_type_only(ccx: @crate_ctxt,
-                                     t: ty::t, name: ~str) ->
-   ~str {
+                                     t: ty::t,
+                                     +name: ~str) -> ~str {
     let s = ppaux::ty_to_short_str(ccx.tcx, t);
     let hash = get_symbol_hash(ccx, t);
     return mangle(ccx.sess,
@@ -648,17 +661,18 @@ fn mangle_internal_name_by_type_only(ccx: @crate_ctxt,
                     path_name(ccx.sess.ident_of(hash))]);
 }
 
-fn mangle_internal_name_by_path_and_seq(ccx: @crate_ctxt, path: path,
-                                        flav: ~str) -> ~str {
+fn mangle_internal_name_by_path_and_seq(ccx: @crate_ctxt,
+                                        +path: path,
+                                        +flav: ~str) -> ~str {
     return mangle(ccx.sess,
                   vec::append_one(path, path_name((ccx.names)(flav))));
 }
 
-fn mangle_internal_name_by_path(ccx: @crate_ctxt, path: path) -> ~str {
+fn mangle_internal_name_by_path(ccx: @crate_ctxt, +path: path) -> ~str {
     return mangle(ccx.sess, path);
 }
 
-fn mangle_internal_name_by_seq(ccx: @crate_ctxt, flav: ~str) -> ~str {
+fn mangle_internal_name_by_seq(ccx: @crate_ctxt, +flav: ~str) -> ~str {
     return fmt!("%s_%u", flav, (ccx.names)(flav).repr);
 }
 
@@ -669,7 +683,7 @@ fn link_binary(sess: Session,
                out_filename: &Path,
                lm: link_meta) {
     // Converts a library file-stem into a cc -l argument
-    fn unlib(config: @session::config, stem: ~str) -> ~str {
+    fn unlib(config: @session::config, +stem: ~str) -> ~str {
         if stem.starts_with("lib") &&
             config.os != session::os_win32 {
             stem.slice(3, stem.len())
@@ -689,7 +703,7 @@ fn link_binary(sess: Session,
 
         out_filename.dir_path().push(long_libname)
     } else {
-        *out_filename
+        /*bad*/copy *out_filename
     };
 
     log(debug, ~"output: " + output.to_str());
@@ -736,7 +750,7 @@ fn link_binary(sess: Session,
     }
 
     let ula = cstore::get_used_link_args(cstore);
-    for ula.each |arg| { cc_args.push(*arg); }
+    for ula.each |arg| { cc_args.push(/*bad*/copy *arg); }
 
     // # Extern library linking
 
@@ -746,7 +760,7 @@ fn link_binary(sess: Session,
     // to be found at compile time so it is still entirely up to outside
     // forces to make sure that library can be found at runtime.
 
-    let addl_paths = sess.opts.addl_lib_search_paths;
+    let addl_paths = /*bad*/copy sess.opts.addl_lib_search_paths;
     for addl_paths.each |path| { cc_args.push(~"-L" + path.to_str()); }
 
     // The names of the extern libraries
diff --git a/src/librustc/back/rpath.rs b/src/librustc/back/rpath.rs
index adb0b659b14..c6b43ff6ad5 100644
--- a/src/librustc/back/rpath.rs
+++ b/src/librustc/back/rpath.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use driver::session;
 use metadata::cstore;
 use metadata::filesearch;
@@ -45,7 +46,7 @@ fn get_rpath_flags(sess: session::Session, out_filename: &Path) -> ~[~str] {
     // where rustrt is and we know every rust program needs it
     let libs = vec::append_one(libs, get_sysroot_absolute_rt_lib(sess));
 
-    let target_triple = sess.opts.target_triple;
+    let target_triple = /*bad*/copy sess.opts.target_triple;
     let rpaths = get_rpaths(os, &sysroot, output, libs, target_triple);
     rpaths_to_flags(rpaths)
 }
@@ -139,8 +140,8 @@ fn get_relative_to(abs1: &Path, abs2: &Path) -> Path {
     let abs2 = abs2.normalize();
     debug!("finding relative path from %s to %s",
            abs1.to_str(), abs2.to_str());
-    let split1 = abs1.components;
-    let split2 = abs2.components;
+    let split1 = /*bad*/copy abs1.components;
+    let split2 = /*bad*/copy abs2.components;
     let len1 = vec::len(split1);
     let len2 = vec::len(split2);
     assert len1 > 0;
@@ -190,7 +191,7 @@ fn minimize_rpaths(rpaths: &[Path]) -> ~[Path] {
     for rpaths.each |rpath| {
         let s = rpath.to_str();
         if !set.contains_key(s) {
-            minimized.push(*rpath);
+            minimized.push(/*bad*/copy *rpath);
             set.insert(s, ());
         }
     }
diff --git a/src/librustc/back/target_strs.rs b/src/librustc/back/target_strs.rs
index 709375dc62f..490ba574c53 100644
--- a/src/librustc/back/target_strs.rs
+++ b/src/librustc/back/target_strs.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 type t = {
     module_asm: ~str,
     meta_sect_name: ~str,
diff --git a/src/librustc/back/upcall.rs b/src/librustc/back/upcall.rs
index 1d992683faa..5c9bdcf14ec 100644
--- a/src/librustc/back/upcall.rs
+++ b/src/librustc/back/upcall.rs
@@ -36,8 +36,10 @@ fn declare_upcalls(targ_cfg: @session::config,
     fn nothrow(f: ValueRef) -> ValueRef {
         base::set_no_unwind(f); f
     }
-    let d = |a,b,c| decl(llmod, ~"upcall_", a, b, c);
-    let dv = |a,b| decl(llmod, ~"upcall_", a, b, T_void());
+    let d: &fn(+a: ~str, +b: ~[TypeRef], +c: TypeRef) -> ValueRef =
+        |a,b,c| decl(llmod, ~"upcall_", a, b, c);
+    let dv: &fn(+a: ~str, +b: ~[TypeRef]) -> ValueRef =
+        |a,b| decl(llmod, ~"upcall_", a, b, T_void());
 
     let int_t = T_int(targ_cfg);
 
diff --git a/src/librustc/back/x86.rs b/src/librustc/back/x86.rs
index 43f134702cb..205867feb3d 100644
--- a/src/librustc/back/x86.rs
+++ b/src/librustc/back/x86.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::target_strs;
 use driver::session;
 use metadata::loader::meta_section_name;
diff --git a/src/librustc/back/x86_64.rs b/src/librustc/back/x86_64.rs
index 1d459aaa6f3..929634e5bd3 100644
--- a/src/librustc/back/x86_64.rs
+++ b/src/librustc/back/x86_64.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::target_strs;
 use driver::session;
 use metadata::loader::meta_section_name;
diff --git a/src/librustc/driver/driver.rs b/src/librustc/driver/driver.rs
index db15a572082..12573e0fc62 100644
--- a/src/librustc/driver/driver.rs
+++ b/src/librustc/driver/driver.rs
@@ -9,6 +9,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::link;
 use back::{x86, x86_64};
 use front;
@@ -66,7 +67,7 @@ fn source_name(input: input) -> ~str {
     }
 }
 
-fn default_configuration(sess: Session, argv0: ~str, input: input) ->
+fn default_configuration(sess: Session, +argv0: ~str, input: input) ->
    ast::crate_cfg {
     let libc = match sess.targ_cfg.os {
       session::os_win32 => ~"msvcrt.dll",
@@ -96,20 +97,21 @@ fn default_configuration(sess: Session, argv0: ~str, input: input) ->
          mk(~"build_input", source_name(input))];
 }
 
-fn append_configuration(cfg: ast::crate_cfg, name: ~str) -> ast::crate_cfg {
-    if attr::contains_name(cfg, name) {
+fn append_configuration(+cfg: ast::crate_cfg, +name: ~str) -> ast::crate_cfg {
+    // XXX: Bad copy.
+    if attr::contains_name(copy cfg, copy name) {
         return cfg;
     } else {
         return vec::append_one(cfg, attr::mk_word_item(name));
     }
 }
 
-fn build_configuration(sess: Session, argv0: ~str, input: input) ->
+fn build_configuration(sess: Session, +argv0: ~str, input: input) ->
    ast::crate_cfg {
     // Combine the configuration requested by the session (command line) with
     // some default and generated configuration items
     let default_cfg = default_configuration(sess, argv0, input);
-    let user_cfg = sess.opts.cfg;
+    let user_cfg = /*bad*/copy sess.opts.cfg;
     // If the user wants a test runner, then add the test cfg
     let user_cfg = append_configuration(
         user_cfg,
@@ -128,7 +130,7 @@ fn parse_cfgspecs(cfgspecs: ~[~str]) -> ast::crate_cfg {
     // meta_word variant.
     let mut words = ~[];
     for cfgspecs.each |s| {
-        words.push(attr::mk_word_item(*s));
+        words.push(attr::mk_word_item(/*bad*/copy *s));
     }
     return words;
 }
@@ -140,7 +142,7 @@ enum input {
     str_input(~str)
 }
 
-fn parse_input(sess: Session, cfg: ast::crate_cfg, input: input)
+fn parse_input(sess: Session, +cfg: ast::crate_cfg, input: input)
     -> @ast::crate {
     match input {
       file_input(ref file) => {
@@ -149,7 +151,7 @@ fn parse_input(sess: Session, cfg: ast::crate_cfg, input: input)
       str_input(ref src) => {
         // FIXME (#2319): Don't really want to box the source string
         parse::parse_crate_from_source_str(
-            anon_src(), @(*src), cfg, sess.parse_sess)
+            anon_src(), @(/*bad*/copy *src), cfg, sess.parse_sess)
       }
     }
 }
@@ -326,7 +328,7 @@ fn compile_upto(sess: Session, cfg: ast::crate_cfg,
     return {crate: crate, tcx: None};
 }
 
-fn compile_input(sess: Session, cfg: ast::crate_cfg, input: input,
+fn compile_input(sess: Session, +cfg: ast::crate_cfg, input: input,
                  outdir: &Option<Path>, output: &Option<Path>) {
 
     let upto = if sess.opts.parse_only { cu_parse }
@@ -336,7 +338,7 @@ fn compile_input(sess: Session, cfg: ast::crate_cfg, input: input,
     compile_upto(sess, cfg, input, upto, Some(outputs));
 }
 
-fn pretty_print_input(sess: Session, cfg: ast::crate_cfg, input: input,
+fn pretty_print_input(sess: Session, +cfg: ast::crate_cfg, input: input,
                       ppm: pp_mode) {
     fn ann_paren_for_expr(node: pprust::ann_node) {
         match node {
@@ -482,7 +484,7 @@ fn host_triple() -> ~str {
         };
 }
 
-fn build_session_options(binary: ~str,
+fn build_session_options(+binary: ~str,
                          matches: &getopts::Matches,
                          demitter: diagnostic::emitter) -> @session::options {
     let crate_type = if opt_present(matches, ~"lib") {
@@ -527,7 +529,7 @@ fn build_session_options(binary: ~str,
     for debug_flags.each |debug_flag| {
         let mut this_bit = 0u;
         for debug_map.each |pair| {
-            let (name, _, bit) = *pair;
+            let (name, _, bit) = /*bad*/copy *pair;
             if name == *debug_flag { this_bit = bit; break; }
         }
         if this_bit == 0u {
@@ -588,7 +590,7 @@ fn build_session_options(binary: ~str,
     let target =
         match target_opt {
             None => host_triple(),
-            Some(ref s) => (*s)
+            Some(ref s) => (/*bad*/copy *s)
         };
 
     let addl_lib_search_paths =
@@ -641,7 +643,7 @@ fn build_session_(sopts: @session::options,
     let filesearch = filesearch::mk_filesearch(
         sopts.maybe_sysroot,
         sopts.target_triple,
-        sopts.addl_lib_search_paths);
+        /*bad*/copy sopts.addl_lib_search_paths);
     let lint_settings = lint::mk_lint_settings();
     Session_(@{targ_cfg: target_cfg,
                opts: sopts,
@@ -768,7 +770,7 @@ fn build_output_filenames(input: input,
         // have to make up a name
         // We want to toss everything after the final '.'
         let dirpath = match *odir {
-          Some(ref d) => (*d),
+          Some(ref d) => (/*bad*/copy *d),
           None => match input {
             str_input(_) => os::getcwd(),
             file_input(ref ifile) => (*ifile).dir_path()
@@ -790,9 +792,9 @@ fn build_output_filenames(input: input,
       }
 
       Some(ref out_file) => {
-        out_path = (*out_file);
+        out_path = (/*bad*/copy *out_file);
         obj_path = if stop_after_codegen {
-            (*out_file)
+            (/*bad*/copy *out_file)
         } else {
             (*out_file).with_filetype(obj_suffix)
         };
diff --git a/src/librustc/driver/session.rs b/src/librustc/driver/session.rs
index 8ea5052afaf..d645ec2d9b0 100644
--- a/src/librustc/driver/session.rs
+++ b/src/librustc/driver/session.rs
@@ -208,8 +208,7 @@ impl Session {
     fn unimpl(msg: ~str) -> ! {
         self.span_diagnostic.handler().unimpl(msg)
     }
-    fn span_lint_level(level: lint::level,
-                       sp: span, msg: ~str) {
+    fn span_lint_level(level: lint::level, sp: span, +msg: ~str) {
         match level {
           lint::allow => { },
           lint::warn => self.span_warn(sp, msg),
@@ -219,8 +218,10 @@ impl Session {
         }
     }
     fn span_lint(lint_mode: lint::lint,
-                 expr_id: ast::node_id, item_id: ast::node_id,
-                 span: span, msg: ~str) {
+                 expr_id: ast::node_id,
+                 item_id: ast::node_id,
+                 span: span,
+                 +msg: ~str) {
         let level = lint::get_lint_settings_level(
             self.lint_settings, lint_mode, expr_id, item_id);
         self.span_lint_level(level, span, msg);
@@ -258,9 +259,9 @@ impl Session {
     }
 
     fn str_of(id: ast::ident) -> ~str {
-        *self.parse_sess.interner.get(id)
+        /*bad*/copy *self.parse_sess.interner.get(id)
     }
-    fn ident_of(st: ~str) -> ast::ident {
+    fn ident_of(+st: ~str) -> ast::ident {
         self.parse_sess.interner.intern(@st)
     }
     fn intr() -> @syntax::parse::token::ident_interner {
diff --git a/src/librustc/front/config.rs b/src/librustc/front/config.rs
index fc1f8d06bb1..7a073057f0d 100644
--- a/src/librustc/front/config.rs
+++ b/src/librustc/front/config.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use syntax::{ast, fold, attr};
 
 use core::option;
@@ -17,7 +18,7 @@ export strip_unconfigured_items;
 export metas_in_cfg;
 export strip_items;
 
-type in_cfg_pred = fn@(~[ast::attribute]) -> bool;
+type in_cfg_pred = fn@(+attrs: ~[ast::attribute]) -> bool;
 
 type ctxt = @{
     in_cfg: in_cfg_pred
@@ -27,7 +28,7 @@ type ctxt = @{
 // any items that do not belong in the current configuration
 fn strip_unconfigured_items(crate: @ast::crate) -> @ast::crate {
     do strip_items(crate) |attrs| {
-        in_cfg(crate.node.config, attrs)
+        in_cfg(/*bad*/copy crate.node.config, attrs)
     }
 }
 
@@ -40,7 +41,10 @@ fn strip_items(crate: @ast::crate, in_cfg: in_cfg_pred)
         @{fold_mod: |a,b| fold_mod(ctxt, a, b),
           fold_block: fold::wrap(|a,b| fold_block(ctxt, a, b) ),
           fold_foreign_mod: |a,b| fold_foreign_mod(ctxt, a, b),
-          fold_item_underscore: |a,b| fold_item_underscore(ctxt, a, b),
+          fold_item_underscore: |a,b| {
+            // Bad copy.
+            fold_item_underscore(ctxt, copy a, b)
+          },
           .. *fold::default_ast_fold()};
 
     let fold = fold::make_fold(precursor);
@@ -94,18 +98,18 @@ fn fold_foreign_mod(cx: ctxt, nm: ast::foreign_mod,
     };
 }
 
-fn fold_item_underscore(cx: ctxt, item: ast::item_,
+fn fold_item_underscore(cx: ctxt, +item: ast::item_,
                         fld: fold::ast_fold) -> ast::item_ {
     let item = match item {
         ast::item_impl(a, b, c, methods) => {
             let methods = methods.filter(|m| method_in_cfg(cx, *m) );
             ast::item_impl(a, b, c, methods)
         }
-        ast::item_trait(a, b, ref methods) => {
+        ast::item_trait(ref a, ref b, ref methods) => {
             let methods = methods.filter(|m| trait_method_in_cfg(cx, m) );
-            ast::item_trait(a, b, methods)
+            ast::item_trait(/*bad*/copy *a, /*bad*/copy *b, methods)
         }
-        _ => item
+        item => item
     };
 
     fold::noop_fold_item_underscore(item, fld)
@@ -131,7 +135,7 @@ fn filter_stmt(cx: ctxt, &&stmt: @ast::stmt) ->
 fn fold_block(cx: ctxt, b: ast::blk_, fld: fold::ast_fold) ->
    ast::blk_ {
     let filtered_stmts = vec::filter_map(b.stmts, |a| filter_stmt(cx, *a));
-    return {view_items: b.view_items,
+    return {view_items: /*bad*/copy b.view_items,
          stmts: vec::map(filtered_stmts, |x| fld.fold_stmt(*x)),
          expr: option::map(&b.expr, |x| fld.fold_expr(*x)),
          id: b.id,
@@ -139,36 +143,35 @@ fn fold_block(cx: ctxt, b: ast::blk_, fld: fold::ast_fold) ->
 }
 
 fn item_in_cfg(cx: ctxt, item: @ast::item) -> bool {
-    return (cx.in_cfg)(item.attrs);
+    return (cx.in_cfg)(/*bad*/copy item.attrs);
 }
 
 fn foreign_item_in_cfg(cx: ctxt, item: @ast::foreign_item) -> bool {
-    return (cx.in_cfg)(item.attrs);
+    return (cx.in_cfg)(/*bad*/copy item.attrs);
 }
 
 fn view_item_in_cfg(cx: ctxt, item: @ast::view_item) -> bool {
-    return (cx.in_cfg)(item.attrs);
+    return (cx.in_cfg)(/*bad*/copy item.attrs);
 }
 
 fn method_in_cfg(cx: ctxt, meth: @ast::method) -> bool {
-    return (cx.in_cfg)(meth.attrs);
+    return (cx.in_cfg)(/*bad*/copy meth.attrs);
 }
 
 fn trait_method_in_cfg(cx: ctxt, meth: &ast::trait_method) -> bool {
     match *meth {
-        ast::required(ref meth) => (cx.in_cfg)(meth.attrs),
-        ast::provided(@ref meth) => (cx.in_cfg)(meth.attrs)
+        ast::required(ref meth) => (cx.in_cfg)(/*bad*/copy meth.attrs),
+        ast::provided(@ref meth) => (cx.in_cfg)(/*bad*/copy meth.attrs)
     }
 }
 
 // Determine if an item should be translated in the current crate
 // configuration based on the item's attributes
-fn in_cfg(cfg: ast::crate_cfg, attrs: ~[ast::attribute]) -> bool {
+fn in_cfg(+cfg: ast::crate_cfg, +attrs: ~[ast::attribute]) -> bool {
     metas_in_cfg(cfg, attr::attr_metas(attrs))
 }
 
-fn metas_in_cfg(cfg: ast::crate_cfg, metas: ~[@ast::meta_item]) -> bool {
-
+fn metas_in_cfg(cfg: ast::crate_cfg, +metas: ~[@ast::meta_item]) -> bool {
     // The "cfg" attributes on the item
     let cfg_metas = attr::find_meta_items_by_name(metas, ~"cfg");
 
@@ -182,7 +185,7 @@ fn metas_in_cfg(cfg: ast::crate_cfg, metas: ~[@ast::meta_item]) -> bool {
     if !has_cfg_metas { return true; }
 
     for cfg_metas.each |cfg_mi| {
-        if attr::contains(cfg, *cfg_mi) { return true; }
+        if attr::contains(/*bad*/copy cfg, *cfg_mi) { return true; }
     }
 
     return false;
diff --git a/src/librustc/front/core_inject.rs b/src/librustc/front/core_inject.rs
index 9575c4695f8..6df5e367ad1 100644
--- a/src/librustc/front/core_inject.rs
+++ b/src/librustc/front/core_inject.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use driver::session::Session;
 
 use core::vec;
@@ -61,10 +62,14 @@ fn inject_libcore_ref(sess: Session,
                         span: dummy_sp()};
 
             let vis = vec::append(~[vi1], crate.module.view_items);
-            let mut new_module = { view_items: vis, ..crate.module };
+            let mut new_module = {
+                view_items: vis,
+                ../*bad*/copy crate.module
+            };
             new_module = fld.fold_mod(new_module);
 
-            let new_crate = { module: new_module, ..crate };
+            // XXX: Bad copy.
+            let new_crate = { module: new_module, ..copy crate };
             (new_crate, span)
         },
         fold_mod: |module, fld| {
@@ -80,7 +85,9 @@ fn inject_libcore_ref(sess: Session,
                         span: dummy_sp()};
 
             let vis = vec::append(~[vi2], module.view_items);
-            let new_module = { view_items: vis, ..module };
+
+            // XXX: Bad copy.
+            let new_module = { view_items: vis, ..copy module };
             fold::noop_fold_mod(new_module, fld)
         },
         ..*fold::default_ast_fold()
diff --git a/src/librustc/front/intrinsic_inject.rs b/src/librustc/front/intrinsic_inject.rs
index e8b15ac1c1f..08b61557fdd 100644
--- a/src/librustc/front/intrinsic_inject.rs
+++ b/src/librustc/front/intrinsic_inject.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use driver::session::Session;
 use syntax::parse;
 use syntax::ast;
@@ -21,7 +22,7 @@ fn inject_intrinsic(sess: Session, crate: @ast::crate) -> @ast::crate {
 
     let item = parse::parse_item_from_source_str(~"<intrinsic>",
                                                  intrinsic_module,
-                                                 sess.opts.cfg,
+                                                 /*bad*/copy sess.opts.cfg,
                                                  ~[],
                                                  sess.parse_sess);
     let item =
@@ -34,6 +35,6 @@ fn inject_intrinsic(sess: Session, crate: @ast::crate) -> @ast::crate {
 
     let items = vec::append(~[item], crate.node.module.items);
 
-    return @{node: {module: { items: items ,.. crate.node.module }
-                 ,.. crate.node} ,.. *crate }
+    return @{node: {module: { items: items ,.. /*bad*/copy crate.node.module }
+                 ,.. /*bad*/copy crate.node} ,.. /*bad*/copy *crate }
 }
diff --git a/src/librustc/front/test.rs b/src/librustc/front/test.rs
index c1e940d6f24..555ef837047 100644
--- a/src/librustc/front/test.rs
+++ b/src/librustc/front/test.rs
@@ -10,6 +10,7 @@
 
 // Code that generates a test runner to run all the tests in a crate
 
+
 use driver::session;
 use front::config;
 use session::Session;
@@ -45,7 +46,7 @@ fn modify_for_testing(sess: session::Session,
     // We generate the test harness when building in the 'test'
     // configuration, either with the '--test' or '--cfg test'
     // command line options.
-    let should_test = attr::contains(crate.node.config,
+    let should_test = attr::contains(/*bad*/copy crate.node.config,
                                      attr::mk_word_item(~"test"));
 
     if should_test {
@@ -101,7 +102,7 @@ fn fold_mod(cx: test_ctxt, m: ast::_mod, fld: fold::ast_fold) -> ast::_mod {
     }
 
     let mod_nomain =
-        {view_items: m.view_items,
+        {view_items: /*bad*/copy m.view_items,
          items: vec::filter_map(m.items, |i| nomain(cx, *i))};
     return fold::noop_fold_mod(mod_nomain, fld);
 }
@@ -112,7 +113,7 @@ fn fold_crate(cx: test_ctxt, c: ast::crate_, fld: fold::ast_fold) ->
 
     // Add a special __test module to the crate that will contain code
     // generated for the test harness
-    return {module: add_test_module(cx, folded.module),.. folded};
+    return {module: add_test_module(cx, /*bad*/copy folded.module),.. folded};
 }
 
 
@@ -133,7 +134,7 @@ fn fold_item(cx: test_ctxt, &&i: @ast::item, fld: fold::ast_fold) ->
           _ => {
             debug!("this is a test function");
             let test = {span: i.span,
-                        path: cx.path, ignore: is_ignored(cx, i),
+                        path: /*bad*/copy cx.path, ignore: is_ignored(cx, i),
                         should_fail: should_fail(i)};
             cx.testfns.push(test);
             debug!("have %u test functions", cx.testfns.len());
@@ -151,7 +152,7 @@ fn is_test_fn(i: @ast::item) -> bool {
         vec::len(attr::find_attrs_by_name(i.attrs, ~"test")) > 0u;
 
     fn has_test_signature(i: @ast::item) -> bool {
-        match i.node {
+        match /*bad*/copy i.node {
           ast::item_fn(decl, _, tps, _) => {
             let input_cnt = vec::len(decl.inputs);
             let no_output = match decl.output.node {
@@ -169,12 +170,13 @@ fn is_test_fn(i: @ast::item) -> bool {
 }
 
 fn is_ignored(cx: test_ctxt, i: @ast::item) -> bool {
-    let ignoreattrs = attr::find_attrs_by_name(i.attrs, ~"ignore");
+    let ignoreattrs = attr::find_attrs_by_name(/*bad*/copy i.attrs,
+                                               ~"ignore");
     let ignoreitems = attr::attr_metas(ignoreattrs);
     let cfg_metas = vec::concat(vec::filter_map(ignoreitems,
         |i| attr::get_meta_item_list(*i)));
     return if vec::is_not_empty(ignoreitems) {
-        config::metas_in_cfg(cx.crate.node.config, cfg_metas)
+        config::metas_in_cfg(/*bad*/copy cx.crate.node.config, cfg_metas)
     } else {
         false
     }
@@ -184,9 +186,9 @@ fn should_fail(i: @ast::item) -> bool {
     vec::len(attr::find_attrs_by_name(i.attrs, ~"should_fail")) > 0u
 }
 
-fn add_test_module(cx: test_ctxt, m: ast::_mod) -> ast::_mod {
+fn add_test_module(cx: test_ctxt, +m: ast::_mod) -> ast::_mod {
     let testmod = mk_test_module(cx);
-    return {items: vec::append_one(m.items, testmod),.. m};
+    return {items: vec::append_one(/*bad*/copy m.items, testmod),.. m};
 }
 
 /*
@@ -228,7 +230,7 @@ fn mk_test_module(cx: test_ctxt) -> @ast::item {
          span: dummy_sp()};
 
     debug!("Synthetic test module:\n%s\n",
-           pprust::item_to_str(@item, cx.sess.intr()));
+           pprust::item_to_str(@copy item, cx.sess.intr()));
 
     return @item;
 }
@@ -237,11 +239,11 @@ fn nospan<T: Copy>(t: T) -> ast::spanned<T> {
     return {node: t, span: dummy_sp()};
 }
 
-fn path_node(ids: ~[ast::ident]) -> @ast::path {
+fn path_node(+ids: ~[ast::ident]) -> @ast::path {
     @{span: dummy_sp(), global: false, idents: ids, rp: None, types: ~[]}
 }
 
-fn path_node_global(ids: ~[ast::ident]) -> @ast::path {
+fn path_node_global(+ids: ~[ast::ident]) -> @ast::path {
     @{span: dummy_sp(), global: true, idents: ids, rp: None, types: ~[]}
 }
 
@@ -271,11 +273,11 @@ fn mk_tests(cx: test_ctxt) -> @ast::item {
     return @item;
 }
 
-fn mk_path(cx: test_ctxt, path: ~[ast::ident]) -> ~[ast::ident] {
+fn mk_path(cx: test_ctxt, +path: ~[ast::ident]) -> ~[ast::ident] {
     // For tests that are inside of std we don't want to prefix
     // the paths with std::
     let is_std = {
-        let items = attr::find_linkage_metas(cx.crate.node.attrs);
+        let items = attr::find_linkage_metas(/*bad*/copy cx.crate.node.attrs);
         match attr::last_meta_item_value_str_by_name(items, ~"name") {
           Some(~"std") => true,
           _ => false
@@ -325,14 +327,15 @@ fn mk_test_desc_vec(cx: test_ctxt) -> @ast::expr {
 
 fn mk_test_desc_rec(cx: test_ctxt, test: test) -> @ast::expr {
     let span = test.span;
-    let path = test.path;
+    let path = /*bad*/copy test.path;
 
     debug!("encoding %s", ast_util::path_name_i(path,
                                                 cx.sess.parse_sess.interner));
 
+    // XXX: Bad copy of `path`.
     let name_lit: ast::lit =
-        nospan(ast::lit_str(@ast_util::path_name_i(path, cx.sess.parse_sess
-                                                   .interner)));
+        nospan(ast::lit_str(@ast_util::path_name_i(
+            copy path, cx.sess.parse_sess.interner)));
     let name_expr_inner: @ast::expr =
         @{id: cx.sess.next_node_id(),
           callee_id: cx.sess.next_node_id(),
@@ -401,7 +404,7 @@ fn mk_test_desc_rec(cx: test_ctxt, test: test) -> @ast::expr {
 
 // FIXME (#1281): This can go away once fn is the type of bare function.
 fn mk_test_wrapper(cx: test_ctxt,
-                   fn_path_expr: ast::expr,
+                   +fn_path_expr: ast::expr,
                    span: span) -> @ast::expr {
     let call_expr: ast::expr = {
         id: cx.sess.next_node_id(),
diff --git a/src/librustc/lib/llvm.rs b/src/librustc/lib/llvm.rs
index dbfe3122388..62956341189 100644
--- a/src/librustc/lib/llvm.rs
+++ b/src/librustc/lib/llvm.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use core::cast;
 use core::cmp;
 use core::int;
@@ -1070,8 +1071,9 @@ fn SetLinkage(Global: ValueRef, Link: Linkage) {
 type type_names = @{type_names: HashMap<TypeRef, ~str>,
                     named_types: HashMap<~str, TypeRef>};
 
-fn associate_type(tn: type_names, s: ~str, t: TypeRef) {
-    assert tn.type_names.insert(t, s);
+fn associate_type(tn: type_names, +s: ~str, t: TypeRef) {
+    // XXX: Bad copy, use @str instead?
+    assert tn.type_names.insert(t, copy s);
     assert tn.named_types.insert(s, t);
 }
 
@@ -1079,7 +1081,7 @@ fn type_has_name(tn: type_names, t: TypeRef) -> Option<~str> {
     return tn.type_names.find(t);
 }
 
-fn name_has_type(tn: type_names, s: ~str) -> Option<TypeRef> {
+fn name_has_type(tn: type_names, +s: ~str) -> Option<TypeRef> {
     return tn.named_types.find(s);
 }
 
@@ -1092,14 +1094,15 @@ fn type_to_str(names: type_names, ty: TypeRef) -> ~str {
     return type_to_str_inner(names, ~[], ty);
 }
 
-fn type_to_str_inner(names: type_names, outer0: ~[TypeRef], ty: TypeRef) ->
+fn type_to_str_inner(names: type_names, +outer0: ~[TypeRef], ty: TypeRef) ->
    ~str {
     match type_has_name(names, ty) {
-      option::Some(ref n) => return (*n),
+      option::Some(ref n) => return (/*bad*/copy *n),
       _ => {}
     }
 
-    let outer = vec::append_one(outer0, ty);
+    // XXX: Bad copy.
+    let outer = vec::append_one(copy outer0, ty);
 
     let kind = llvm::LLVMGetTypeKind(ty);
 
diff --git a/src/librustc/metadata/common.rs b/src/librustc/metadata/common.rs
index 1c821480df4..e6a367ac1a8 100644
--- a/src/librustc/metadata/common.rs
+++ b/src/librustc/metadata/common.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // EBML enum definitions and utils shared by the encoder and decoder
 
 const tag_items: uint = 0x02u;
diff --git a/src/librustc/metadata/creader.rs b/src/librustc/metadata/creader.rs
index 8a4aa78fe44..da33aaa460b 100644
--- a/src/librustc/metadata/creader.rs
+++ b/src/librustc/metadata/creader.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 //! Validates all used crates and extern libraries and loads their metadata
 
 use metadata::cstore;
@@ -79,7 +80,8 @@ fn warn_if_multiple_versions(e: env, diag: span_handler,
     use either::*;
 
     if crate_cache.len() != 0u {
-        let name = loader::crate_name_from_metas(*crate_cache.last().metas);
+        let name = loader::crate_name_from_metas(
+            /*bad*/copy *crate_cache.last().metas);
         let (matches, non_matches) =
             partition(crate_cache.map_to_vec(|&entry| {
                 let othername = loader::crate_name_from_metas(*entry.metas);
@@ -98,7 +100,8 @@ fn warn_if_multiple_versions(e: env, diag: span_handler,
             for matches.each |match_| {
                 diag.span_note(match_.span, ~"used here");
                 let attrs = ~[
-                    attr::mk_attr(attr::mk_list_item(~"link", *match_.metas))
+                    attr::mk_attr(attr::mk_list_item(
+                        ~"link", /*bad*/copy *match_.metas))
                 ];
                 loader::note_linkage_attrs(e.intr, diag, attrs);
             }
@@ -118,7 +121,7 @@ type env = @{diag: span_handler,
              intr: @ident_interner};
 
 fn visit_view_item(e: env, i: @ast::view_item) {
-    match i.node {
+    match /*bad*/copy i.node {
       ast::view_item_use(ident, meta_items, id) => {
         debug!("resolving use stmt. ident: %?, meta: %?", ident, meta_items);
         let cnum = resolve_crate(e, ident, meta_items, ~"", i.span);
@@ -129,7 +132,7 @@ fn visit_view_item(e: env, i: @ast::view_item) {
 }
 
 fn visit_item(e: env, i: @ast::item) {
-    match i.node {
+    match /*bad*/copy i.node {
       ast::item_foreign_mod(fm) => {
         match attr::foreign_abi(i.attrs) {
           either::Right(abi) => {
@@ -141,7 +144,8 @@ fn visit_item(e: env, i: @ast::item) {
 
         let cstore = e.cstore;
         let mut already_added = false;
-        let link_args = attr::find_attrs_by_name(i.attrs, ~"link_args");
+        let link_args = attr::find_attrs_by_name(/*bad*/copy i.attrs,
+                                                 ~"link_args");
 
         match fm.sort {
           ast::named => {
@@ -154,9 +158,9 @@ fn visit_item(e: env, i: @ast::item) {
                           i.span,
                           ~"empty #[link_name] not allowed; use #[nolink].");
                    }
-                   (*nn)
+                   (/*bad*/copy *nn)
                  }
-                None => *e.intr.get(i.ident)
+                None => /*bad*/copy *e.intr.get(i.ident)
             };
             if attr::find_attrs_by_name(i.attrs, ~"nolink").is_empty() {
                 already_added = !cstore::add_used_library(cstore,
@@ -173,7 +177,7 @@ fn visit_item(e: env, i: @ast::item) {
         for link_args.each |a| {
             match attr::get_meta_item_value_str(attr::attr_meta(*a)) {
               Some(ref linkarg) => {
-                cstore::add_used_link_args(cstore, (*linkarg));
+                cstore::add_used_link_args(cstore, (/*bad*/copy *linkarg));
               }
               None => {/* fallthrough */ }
             }
@@ -183,9 +187,10 @@ fn visit_item(e: env, i: @ast::item) {
     }
 }
 
-fn metas_with(ident: ~str, key: ~str, metas: ~[@ast::meta_item])
+fn metas_with(+ident: ~str, +key: ~str, +metas: ~[@ast::meta_item])
     -> ~[@ast::meta_item] {
-    let name_items = attr::find_meta_items_by_name(metas, key);
+    // XXX: Bad copies.
+    let name_items = attr::find_meta_items_by_name(copy metas, copy key);
     if name_items.is_empty() {
         vec::append_one(metas, attr::mk_name_value_item_str(key, ident))
     } else {
@@ -193,7 +198,7 @@ fn metas_with(ident: ~str, key: ~str, metas: ~[@ast::meta_item])
     }
 }
 
-fn metas_with_ident(ident: ~str, metas: ~[@ast::meta_item])
+fn metas_with_ident(+ident: ~str, +metas: ~[@ast::meta_item])
     -> ~[@ast::meta_item] {
     metas_with(ident, ~"name", metas)
 }
@@ -210,9 +215,9 @@ fn existing_match(e: env, metas: ~[@ast::meta_item], hash: ~str) ->
     return None;
 }
 
-fn resolve_crate(e: env, ident: ast::ident, metas: ~[@ast::meta_item],
-                 hash: ~str, span: span) -> ast::crate_num {
-    let metas = metas_with_ident(*e.intr.get(ident), metas);
+fn resolve_crate(e: env, ident: ast::ident, +metas: ~[@ast::meta_item],
+                 +hash: ~str, span: span) -> ast::crate_num {
+    let metas = metas_with_ident(/*bad*/copy *e.intr.get(ident), metas);
 
     match existing_match(e, metas, hash) {
       None => {
@@ -221,7 +226,7 @@ fn resolve_crate(e: env, ident: ast::ident, metas: ~[@ast::meta_item],
             filesearch: e.filesearch,
             span: span,
             ident: ident,
-            metas: metas,
+            metas: copy metas,  // XXX: Bad copy.
             hash: hash,
             os: e.os,
             static: e.static,
@@ -247,8 +252,8 @@ fn resolve_crate(e: env, ident: ast::ident, metas: ~[@ast::meta_item],
 
         let cname =
             match attr::last_meta_item_value_str_by_name(metas, ~"name") {
-              option::Some(ref v) => (*v),
-              option::None => *e.intr.get(ident)
+              option::Some(ref v) => (/*bad*/copy *v),
+              option::None => /*bad*/copy *e.intr.get(ident)
             };
         let cmeta = @{name: cname, data: cdata,
                       cnum_map: cnum_map, cnum: cnum};
@@ -273,7 +278,7 @@ fn resolve_crate_deps(e: env, cdata: @~[u8]) -> cstore::cnum_map {
     for decoder::get_crate_deps(e.intr, cdata).each |dep| {
         let extrn_cnum = dep.cnum;
         let cname = dep.name;
-        let cmetas = metas_with(dep.vers, ~"vers", ~[]);
+        let cmetas = metas_with(/*bad*/copy dep.vers, ~"vers", ~[]);
         debug!("resolving dep crate %s ver: %s hash: %s",
                *e.intr.get(dep.name), dep.vers, dep.hash);
         match existing_match(e, metas_with_ident(*e.intr.get(cname), cmetas),
@@ -289,8 +294,8 @@ fn resolve_crate_deps(e: env, cdata: @~[u8]) -> cstore::cnum_map {
             // FIXME (#2404): Need better error reporting than just a bogus
             // span.
             let fake_span = ast_util::dummy_sp();
-            let local_cnum = resolve_crate(e, cname, cmetas, dep.hash,
-                                           fake_span);
+            let local_cnum = resolve_crate(e, cname, cmetas,
+                                           /*bad*/copy dep.hash, fake_span);
             cnum_map.insert(extrn_cnum, local_cnum);
           }
         }
diff --git a/src/librustc/metadata/csearch.rs b/src/librustc/metadata/csearch.rs
index be0f71f0e5d..2dfe5bad27a 100644
--- a/src/librustc/metadata/csearch.rs
+++ b/src/librustc/metadata/csearch.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // Searching for information from the cstore
 
 use metadata::common::*;
@@ -100,7 +101,8 @@ fn get_item_path(tcx: ty::ctxt, def: ast::def_id) -> ast_map::path {
 
     // FIXME #1920: This path is not always correct if the crate is not linked
     // into the root namespace.
-    vec::append(~[ast_map::path_mod(tcx.sess.ident_of(cdata.name))], path)
+    vec::append(~[ast_map::path_mod(tcx.sess.ident_of(
+        /*bad*/copy cdata.name))], path)
 }
 
 enum found_ast {
diff --git a/src/librustc/metadata/cstore.rs b/src/librustc/metadata/cstore.rs
index 5d4694df7d3..b09f2d87b6c 100644
--- a/src/librustc/metadata/cstore.rs
+++ b/src/librustc/metadata/cstore.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // The crate store - a central repo for information collected about external
 // crates and libraries
 
@@ -125,10 +126,10 @@ fn add_used_crate_file(cstore: CStore, lib: &Path) {
 }
 
 fn get_used_crate_files(cstore: CStore) -> ~[Path] {
-    return p(cstore).used_crate_files;
+    return /*bad*/copy p(cstore).used_crate_files;
 }
 
-fn add_used_library(cstore: CStore, lib: ~str) -> bool {
+fn add_used_library(cstore: CStore, +lib: ~str) -> bool {
     assert lib != ~"";
 
     if vec::contains(p(cstore).used_libraries, &lib) { return false; }
@@ -137,7 +138,7 @@ fn add_used_library(cstore: CStore, lib: ~str) -> bool {
 }
 
 fn get_used_libraries(cstore: CStore) -> ~[~str] {
-    return p(cstore).used_libraries;
+    return /*bad*/copy p(cstore).used_libraries;
 }
 
 fn add_used_link_args(cstore: CStore, args: ~str) {
@@ -145,7 +146,7 @@ fn add_used_link_args(cstore: CStore, args: ~str) {
 }
 
 fn get_used_link_args(cstore: CStore) -> ~[~str] {
-    return p(cstore).used_link_args;
+    return /*bad*/copy p(cstore).used_link_args;
 }
 
 fn add_use_stmt_cnum(cstore: CStore, use_id: ast::node_id,
@@ -168,7 +169,7 @@ fn get_dep_hashes(cstore: CStore) -> ~[~str] {
         let cdata = cstore::get_crate_data(cstore, cnum);
         let hash = decoder::get_crate_hash(cdata.data);
         debug!("Add hash[%s]: %s", cdata.name, hash);
-        result.push({name: cdata.name, hash: hash});
+        result.push({name: /*bad*/copy cdata.name, hash: hash});
     };
     pure fn lteq(a: &crate_hash, b: &crate_hash) -> bool {a.name <= b.name}
     let sorted = std::sort::merge_sort(result, lteq);
@@ -176,7 +177,7 @@ fn get_dep_hashes(cstore: CStore) -> ~[~str] {
     for sorted.each |x| {
         debug!("  hash[%s]: %s", x.name, x.hash);
     }
-    fn mapper(ch: &crate_hash) -> ~str { return ch.hash; }
+    fn mapper(ch: &crate_hash) -> ~str { return /*bad*/copy ch.hash; }
     return vec::map(sorted, mapper);
 }
 
diff --git a/src/librustc/metadata/decoder.rs b/src/librustc/metadata/decoder.rs
index 91926ff2f9a..d4cebea66cd 100644
--- a/src/librustc/metadata/decoder.rs
+++ b/src/librustc/metadata/decoder.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // Decoding metadata from a single crate's metadata
 
 use cmd = metadata::cstore::crate_metadata;
@@ -472,7 +473,7 @@ struct path_entry {
     def_like: def_like,
 }
 
-fn path_entry(path_string: ~str, def_like: def_like) -> path_entry {
+fn path_entry(+path_string: ~str, def_like: def_like) -> path_entry {
     path_entry {
         path_string: path_string,
         def_like: def_like
@@ -520,7 +521,8 @@ fn each_path(intr: @ident_interner, cdata: cmd,
                 let def_like = item_to_def_like(item_doc, def_id, cdata.cnum);
 
                 // Hand the information off to the iteratee.
-                let this_path_entry = path_entry(path, def_like);
+                // XXX: Bad copy.
+                let this_path_entry = path_entry(copy path, def_like);
                 if !f(this_path_entry) {
                     broken = true;      // XXX: This is awful.
                 }
@@ -608,7 +610,7 @@ fn maybe_get_item_ast(intr: @ident_interner, cdata: cmd, tcx: ty::ctxt,
     let item_doc = lookup_item(id, cdata.data);
     let path = vec::init(item_path(intr, item_doc));
     match decode_inlined_item(cdata, tcx, path, item_doc) {
-      Some(ref ii) => csearch::found((*ii)),
+      Some(ref ii) => csearch::found((/*bad*/copy *ii)),
       None => {
         match item_parent_item(item_doc) {
           Some(did) => {
@@ -616,7 +618,7 @@ fn maybe_get_item_ast(intr: @ident_interner, cdata: cmd, tcx: ty::ctxt,
             let parent_item = lookup_item(did.node, cdata.data);
             match decode_inlined_item(cdata, tcx, path,
                                                parent_item) {
-              Some(ref ii) => csearch::found_parent(did, (*ii)),
+              Some(ref ii) => csearch::found_parent(did, (/*bad*/copy *ii)),
               None => csearch::not_found
             }
           }
@@ -755,7 +757,7 @@ fn get_trait_methods(intr: @ident_interner, cdata: cmd, id: ast::node_id,
         let ty = doc_type(mth, tcx, cdata);
         let def_id = item_def_id(mth, cdata);
         let fty = match ty::get(ty).sty {
-          ty::ty_fn(ref f) => (*f),
+          ty::ty_fn(ref f) => (/*bad*/copy *f),
           _ => {
             tcx.diag.handler().bug(
                 ~"get_trait_methods: id has non-function type");
@@ -786,7 +788,7 @@ fn get_provided_trait_methods(intr: @ident_interner, cdata: cmd,
 
         let fty;
         match ty::get(ty).sty {
-            ty::ty_fn(ref f) => fty = (*f),
+            ty::ty_fn(ref f) => fty = (/*bad*/copy *f),
             _ => {
                 tcx.diag.handler().bug(~"get_provided_trait_methods(): id \
                                          has non-function type");
@@ -1027,7 +1029,7 @@ fn get_attributes(md: ebml::Doc) -> ~[ast::attribute] {
             assert (vec::len(meta_items) == 1u);
             let meta_item = meta_items[0];
             attrs.push(
-                {node: {style: ast::attr_outer, value: *meta_item,
+                {node: {style: ast::attr_outer, value: /*bad*/copy *meta_item,
                         is_sugared_doc: false},
                  span: ast_util::dummy_sp()});
         };
@@ -1102,19 +1104,20 @@ fn get_crate_vers(data: @~[u8]) -> ~str {
     let attrs = decoder::get_crate_attributes(data);
     return match attr::last_meta_item_value_str_by_name(
         attr::find_linkage_metas(attrs), ~"vers") {
-      Some(ref ver) => (*ver),
+      Some(ref ver) => (/*bad*/copy *ver),
       None => ~"0.0"
     };
 }
 
 fn iter_crate_items(intr: @ident_interner, cdata: cmd,
                     get_crate_data: GetCrateDataCb,
-                    proc: fn(~str, ast::def_id)) {
+                    proc: fn(+path: ~str, ast::def_id)) {
     for each_path(intr, cdata, get_crate_data) |path_entry| {
         match path_entry.def_like {
             dl_impl(*) | dl_field => {}
             dl_def(def) => {
-                proc(path_entry.path_string, ast_util::def_id_of_def(def))
+                proc(/*bad*/copy path_entry.path_string,
+                     ast_util::def_id_of_def(def))
             }
         }
     }
diff --git a/src/librustc/metadata/encoder.rs b/src/librustc/metadata/encoder.rs
index b327e8f3196..5a936e113ee 100644
--- a/src/librustc/metadata/encoder.rs
+++ b/src/librustc/metadata/encoder.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // Metadata encoding
 
 use metadata::common::*;
@@ -233,7 +234,7 @@ fn encode_type(ecx: @encode_ctxt, ebml_w: writer::Encoder, typ: ty::t) {
 fn encode_symbol(ecx: @encode_ctxt, ebml_w: writer::Encoder, id: node_id) {
     ebml_w.start_tag(tag_items_data_item_symbol);
     let sym = match ecx.item_symbols.find(id) {
-      Some(ref x) => (*x),
+      Some(ref x) => (/*bad*/copy *x),
       None => {
         ecx.diag.handler().bug(
             fmt!("encode_symbol: id not found %d", id));
@@ -280,7 +281,7 @@ fn encode_enum_variant_info(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         encode_type(ecx, ebml_w,
                     node_id_to_type(ecx.tcx, variant.node.id));
         match variant.node.kind {
-            ast::tuple_variant_kind(args)
+            ast::tuple_variant_kind(ref args)
                     if args.len() > 0 && ty_params.len() == 0 => {
                 encode_symbol(ecx, ebml_w, variant.node.id);
             }
@@ -292,8 +293,9 @@ fn encode_enum_variant_info(ecx: @encode_ctxt, ebml_w: writer::Encoder,
             encode_disr_val(ecx, ebml_w, vi[i].disr_val);
             disr_val = vi[i].disr_val;
         }
-        encode_type_param_bounds(ebml_w, ecx, ty_params);
-        encode_path(ecx, ebml_w, path, ast_map::path_name(variant.node.name));
+        encode_type_param_bounds(ebml_w, ecx, /*bad*/copy ty_params);
+        encode_path(ecx, ebml_w, /*bad*/copy path,
+                    ast_map::path_name(variant.node.name));
         ebml_w.end_tag();
         disr_val += 1;
         i += 1;
@@ -322,7 +324,7 @@ fn encode_path(ecx: @encode_ctxt, ebml_w: writer::Encoder,
 }
 
 fn encode_info_for_mod(ecx: @encode_ctxt, ebml_w: writer::Encoder,
-                       md: _mod, id: node_id, path: ast_map::path,
+                       md: _mod, id: node_id, +path: ast_map::path,
                        name: ident) {
     ebml_w.start_tag(tag_items_data_item);
     encode_def_id(ebml_w, local_def(id));
@@ -449,7 +451,8 @@ fn encode_info_for_struct(ecx: @encode_ctxt, ebml_w: writer::Encoder,
                        tcx.sess.str_of(nm), id);
                 encode_visibility(ebml_w, vis);
                 encode_name(ecx, ebml_w, nm);
-                encode_path(ecx, ebml_w, path, ast_map::path_name(nm));
+                encode_path(ecx, ebml_w, /*bad*/copy path,
+                            ast_map::path_name(nm));
                 encode_type(ecx, ebml_w, node_id_to_type(tcx, id));
                 encode_mutability(ebml_w, mt);
                 encode_def_id(ebml_w, local_def(id));
@@ -458,13 +461,13 @@ fn encode_info_for_struct(ecx: @encode_ctxt, ebml_w: writer::Encoder,
             unnamed_field => {}
         }
     }
-    *index
+    /*bad*/copy *index
 }
 
 // This is for encoding info for ctors and dtors
 fn encode_info_for_ctor(ecx: @encode_ctxt, ebml_w: writer::Encoder,
-                        id: node_id, ident: ident, path: ast_map::path,
-                        item: Option<inlined_item>, tps: ~[ty_param]) {
+                        id: node_id, ident: ident, +path: ast_map::path,
+                        item: Option<inlined_item>, +tps: ~[ty_param]) {
         ebml_w.start_tag(tag_items_data_item);
         encode_name(ecx, ebml_w, ident);
         encode_def_id(ebml_w, local_def(id));
@@ -475,7 +478,8 @@ fn encode_info_for_ctor(ecx: @encode_ctxt, ebml_w: writer::Encoder,
                ecx.tcx.sess.str_of(ident),
                ty_to_str(ecx.tcx, its_ty), id);
         encode_type(ecx, ebml_w, its_ty);
-        encode_path(ecx, ebml_w, path, ast_map::path_name(ident));
+        // XXX: Bad copy.
+        encode_path(ecx, ebml_w, copy path, ast_map::path_name(ident));
         match item {
            Some(ref it) => {
              (ecx.encode_inlined_item)(ecx, ebml_w, path, (*it));
@@ -487,10 +491,13 @@ fn encode_info_for_ctor(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         ebml_w.end_tag();
 }
 
-fn encode_info_for_method(ecx: @encode_ctxt, ebml_w: writer::Encoder,
-                          impl_path: ast_map::path, should_inline: bool,
+fn encode_info_for_method(ecx: @encode_ctxt,
+                          ebml_w: writer::Encoder,
+                          +impl_path: ast_map::path,
+                          should_inline: bool,
                           parent_id: node_id,
-                          m: @method, all_tps: ~[ty_param]) {
+                          m: @method,
+                          +all_tps: ~[ty_param]) {
     debug!("encode_info_for_method: %d %s %u", m.id,
            ecx.tcx.sess.str_of(m.ident), all_tps.len());
     ebml_w.start_tag(tag_items_data_item);
@@ -501,12 +508,14 @@ fn encode_info_for_method(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         }
         _ => encode_family(ebml_w, purity_fn_family(m.purity))
     }
+    let len = all_tps.len();
     encode_type_param_bounds(ebml_w, ecx, all_tps);
     encode_type(ecx, ebml_w, node_id_to_type(ecx.tcx, m.id));
     encode_name(ecx, ebml_w, m.ident);
-    encode_path(ecx, ebml_w, impl_path, ast_map::path_name(m.ident));
+    // XXX: Bad copy.
+    encode_path(ecx, ebml_w, copy impl_path, ast_map::path_name(m.ident));
     encode_self_type(ebml_w, m.self_ty.node);
-    if all_tps.len() > 0u || should_inline {
+    if len > 0u || should_inline {
         (ecx.encode_inlined_item)(
            ecx, ebml_w, impl_path,
            ii_method(local_def(parent_id), m));
@@ -544,7 +553,7 @@ fn should_inline(attrs: ~[attribute]) -> bool {
 
 fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
                         item: @item, index: @mut ~[entry<int>],
-                        path: ast_map::path) {
+                        +path: ast_map::path) {
 
     let tcx = ecx.tcx;
     let must_write =
@@ -564,7 +573,7 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
     debug!("encoding info for item at %s",
            ecx.tcx.sess.codemap.span_to_str(item.span));
 
-    match item.node {
+    match /*bad*/copy item.node {
       item_const(_, _) => {
         add_to_index();
         ebml_w.start_tag(tag_items_data_item);
@@ -580,11 +589,13 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         ebml_w.start_tag(tag_items_data_item);
         encode_def_id(ebml_w, local_def(item.id));
         encode_family(ebml_w, purity_fn_family(purity));
+        let tps_len = tps.len();
         encode_type_param_bounds(ebml_w, ecx, tps);
         encode_type(ecx, ebml_w, node_id_to_type(tcx, item.id));
-        encode_path(ecx, ebml_w, path, ast_map::path_name(item.ident));
-        encode_attributes(ebml_w, item.attrs);
-        if tps.len() > 0u || should_inline(item.attrs) {
+        // XXX: Bad copy.
+        encode_path(ecx, ebml_w, copy path, ast_map::path_name(item.ident));
+        encode_attributes(ebml_w, /*bad*/copy item.attrs);
+        if tps_len > 0u || should_inline(item.attrs) {
             (ecx.encode_inlined_item)(ecx, ebml_w, path, ii_item(item));
         } else {
             encode_symbol(ecx, ebml_w, item.id);
@@ -616,36 +627,39 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         encode_region_param(ecx, ebml_w, item);
         ebml_w.end_tag();
       }
-      item_enum(ref enum_definition, tps) => {
+      item_enum(ref enum_definition, ref tps) => {
         add_to_index();
         do ebml_w.wr_tag(tag_items_data_item) {
             encode_def_id(ebml_w, local_def(item.id));
             encode_family(ebml_w, 't');
-            encode_type_param_bounds(ebml_w, ecx, tps);
+            encode_type_param_bounds(ebml_w, ecx, /*bad*/copy *tps);
             encode_type(ecx, ebml_w, node_id_to_type(tcx, item.id));
             encode_name(ecx, ebml_w, item.ident);
             for (*enum_definition).variants.each |v| {
                 encode_variant_id(ebml_w, local_def(v.node.id));
             }
-            (ecx.encode_inlined_item)(ecx, ebml_w, path, ii_item(item));
-            encode_path(ecx, ebml_w, path, ast_map::path_name(item.ident));
+            (ecx.encode_inlined_item)(ecx, ebml_w, /*bad*/copy path,
+                                      ii_item(item));
+            encode_path(ecx, ebml_w, /*bad*/copy path,
+                        ast_map::path_name(item.ident));
             encode_region_param(ecx, ebml_w, item);
         }
         encode_enum_variant_info(ecx,
                                  ebml_w,
                                  item.id,
-                                 (*enum_definition).variants,
+                                 /*bad*/copy (*enum_definition).variants,
                                  path,
                                  index,
-                                 tps);
+                                 /*bad*/copy *tps);
       }
       item_struct(struct_def, tps) => {
         /* First, encode the fields
            These come first because we need to write them to make
            the index, and the index needs to be in the item for the
            class itself */
-        let idx = encode_info_for_struct(ecx, ebml_w, path,
-                                        struct_def.fields, index);
+        // XXX: Bad copy of `path`.
+        let idx = encode_info_for_struct(ecx, ebml_w, copy path,
+                                        /*bad*/copy struct_def.fields, index);
         /* Encode the dtor */
         do struct_def.dtor.iter |dtor| {
             index.push({val: dtor.node.id, pos: ebml_w.writer.tell()});
@@ -653,10 +667,10 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
                                ecx.tcx.sess.ident_of(
                                    ecx.tcx.sess.str_of(item.ident) +
                                    ~"_dtor"),
-                               path, if tps.len() > 0u {
+                               /*bad*/copy path, if tps.len() > 0u {
                                    Some(ii_dtor(*dtor, item.ident, tps,
                                                 local_def(item.id))) }
-                               else { None }, tps);
+                               else { None }, /*bad*/copy tps);
         }
 
         /* Index the class*/
@@ -705,10 +719,11 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         encode_def_id(ebml_w, local_def(item.id));
         encode_family(ebml_w, 'i');
         encode_region_param(ecx, ebml_w, item);
-        encode_type_param_bounds(ebml_w, ecx, tps);
+        // XXX: Bad copy.
+        encode_type_param_bounds(ebml_w, ecx, copy tps);
         encode_type(ecx, ebml_w, node_id_to_type(tcx, item.id));
         encode_name(ecx, ebml_w, item.ident);
-        encode_attributes(ebml_w, item.attrs);
+        encode_attributes(ebml_w, /*bad*/copy item.attrs);
         match ty.node {
             ast::ty_path(path, _) if path.idents.len() == 1 => {
                 encode_impl_type_basename(ecx, ebml_w,
@@ -725,19 +740,21 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         do opt_trait.iter() |associated_trait| {
            encode_trait_ref(ebml_w, ecx, *associated_trait);
         }
-        encode_path(ecx, ebml_w, path, ast_map::path_name(item.ident));
+        // XXX: Bad copy.
+        encode_path(ecx, ebml_w, copy path, ast_map::path_name(item.ident));
         ebml_w.end_tag();
 
         let impl_path = vec::append_one(path,
                                         ast_map::path_name(item.ident));
         for methods.each |m| {
             index.push({val: m.id, pos: ebml_w.writer.tell()});
-            encode_info_for_method(ecx, ebml_w, impl_path,
-                                   should_inline(m.attrs), item.id, *m,
-                                   vec::append(tps, m.tps));
+            encode_info_for_method(ecx, ebml_w, /*bad*/copy impl_path,
+                                   should_inline(/*bad*/copy m.attrs),
+                                   item.id, *m,
+                                   vec::append(/*bad*/copy tps, m.tps));
         }
       }
-      item_trait(tps, traits, ref ms) => {
+      item_trait(ref tps, ref traits, ref ms) => {
         let provided_methods = dvec::DVec();
 
         add_to_index();
@@ -745,10 +762,10 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         encode_def_id(ebml_w, local_def(item.id));
         encode_family(ebml_w, 'I');
         encode_region_param(ecx, ebml_w, item);
-        encode_type_param_bounds(ebml_w, ecx, tps);
+        encode_type_param_bounds(ebml_w, ecx, /*bad*/copy *tps);
         encode_type(ecx, ebml_w, node_id_to_type(tcx, item.id));
         encode_name(ecx, ebml_w, item.ident);
-        encode_attributes(ebml_w, item.attrs);
+        encode_attributes(ebml_w, /*bad*/copy item.attrs);
         let mut i = 0u;
         for vec::each(*ty::trait_methods(tcx, local_def(item.id))) |mty| {
             match (*ms)[i] {
@@ -756,8 +773,9 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
                 ebml_w.start_tag(tag_item_trait_method);
                 encode_def_id(ebml_w, local_def((*ty_m).id));
                 encode_name(ecx, ebml_w, mty.ident);
-                encode_type_param_bounds(ebml_w, ecx, (*ty_m).tps);
-                encode_type(ecx, ebml_w, ty::mk_fn(tcx, mty.fty));
+                encode_type_param_bounds(ebml_w, ecx,
+                                         /*bad*/copy (*ty_m).tps);
+                encode_type(ecx, ebml_w, ty::mk_fn(tcx, /*bad*/copy mty.fty));
                 encode_family(ebml_w, purity_fn_family(mty.fty.meta.purity));
                 encode_self_type(ebml_w, mty.self_ty);
                 encode_method_sort(ebml_w, 'r');
@@ -769,8 +787,8 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
                 ebml_w.start_tag(tag_item_trait_method);
                 encode_def_id(ebml_w, local_def(m.id));
                 encode_name(ecx, ebml_w, mty.ident);
-                encode_type_param_bounds(ebml_w, ecx, m.tps);
-                encode_type(ecx, ebml_w, ty::mk_fn(tcx, mty.fty));
+                encode_type_param_bounds(ebml_w, ecx, /*bad*/copy m.tps);
+                encode_type(ecx, ebml_w, ty::mk_fn(tcx, /*bad*/copy mty.fty));
                 encode_family(ebml_w, purity_fn_family(mty.fty.meta.purity));
                 encode_self_type(ebml_w, mty.self_ty);
                 encode_method_sort(ebml_w, 'p');
@@ -779,7 +797,8 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
             }
             i += 1u;
         }
-        encode_path(ecx, ebml_w, path, ast_map::path_name(item.ident));
+        // XXX: Bad copy.
+        encode_path(ecx, ebml_w, copy path, ast_map::path_name(item.ident));
         for traits.each |associated_trait| {
            encode_trait_ref(ebml_w, ecx, *associated_trait)
         }
@@ -805,7 +824,7 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
             let polyty = ecx.tcx.tcache.get(local_def(ty_m.id));
             encode_ty_type_param_bounds(ebml_w, ecx, polyty.bounds);
             encode_type(ecx, ebml_w, polyty.ty);
-            let m_path = vec::append_one(path,
+            let m_path = vec::append_one(/*bad*/copy path,
                                          ast_map::path_name(item.ident));
             encode_path(ecx, ebml_w, m_path, ast_map::path_name(ty_m.ident));
             ebml_w.end_tag();
@@ -814,30 +833,33 @@ fn encode_info_for_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         // Finally, output all the provided methods as items.
         for provided_methods.each |m| {
             index.push({val: m.id, pos: ebml_w.writer.tell()});
-            encode_info_for_method(ecx, ebml_w, path, true, item.id, *m,
-                                   m.tps);
+            encode_info_for_method(ecx, ebml_w, /*bad*/copy path,
+                                   true, item.id, *m, /*bad*/copy m.tps);
         }
       }
       item_mac(*) => fail ~"item macros unimplemented"
     }
 }
 
-fn encode_info_for_foreign_item(ecx: @encode_ctxt, ebml_w: writer::Encoder,
+fn encode_info_for_foreign_item(ecx: @encode_ctxt,
+                                ebml_w: writer::Encoder,
                                 nitem: @foreign_item,
                                 index: @mut ~[entry<int>],
-                                path: ast_map::path, abi: foreign_abi) {
+                                +path: ast_map::path,
+                                abi: foreign_abi) {
     if !reachable(ecx, nitem.id) { return; }
     index.push({val: nitem.id, pos: ebml_w.writer.tell()});
 
     ebml_w.start_tag(tag_items_data_item);
-    match nitem.node {
+    match /*bad*/copy nitem.node {
       foreign_item_fn(_, purity, tps) => {
         encode_def_id(ebml_w, local_def(nitem.id));
         encode_family(ebml_w, purity_fn_family(purity));
         encode_type_param_bounds(ebml_w, ecx, tps);
         encode_type(ecx, ebml_w, node_id_to_type(ecx.tcx, nitem.id));
         if abi == foreign_abi_rust_intrinsic {
-            (ecx.encode_inlined_item)(ecx, ebml_w, path,
+            // XXX: Bad copy of `path`.
+            (ecx.encode_inlined_item)(ecx, ebml_w, copy path,
                                       ii_foreign(nitem));
         } else {
             encode_symbol(ecx, ebml_w, nitem.id);
@@ -869,7 +891,7 @@ fn encode_info_for_items(ecx: @encode_ctxt, ebml_w: writer::Encoder,
             visit::visit_item(i, cx, v);
             match ecx.tcx.items.get(i.id) {
               ast_map::node_item(_, pt) => {
-                encode_info_for_item(ecx, ebml_w, i, index, *pt);
+                encode_info_for_item(ecx, ebml_w, i, index, /*bad*/copy *pt);
               }
               _ => fail ~"bad item"
             }
@@ -879,7 +901,7 @@ fn encode_info_for_items(ecx: @encode_ctxt, ebml_w: writer::Encoder,
             match ecx.tcx.items.get(ni.id) {
               ast_map::node_foreign_item(_, abi, pt) => {
                 encode_info_for_foreign_item(ecx, ebml_w, ni,
-                                             index, *pt, abi);
+                                             index, /*bad*/copy *pt, abi);
               }
               // case for separate item and foreign-item tables
               _ => fail ~"bad foreign item"
@@ -888,7 +910,7 @@ fn encode_info_for_items(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         ,.. *visit::default_visitor()
     }));
     ebml_w.end_tag();
-    return *index;
+    return /*bad*/copy *index;
 }
 
 
@@ -905,7 +927,7 @@ fn create_index<T: Copy Hash IterBytes>(index: ~[entry<T>]) ->
 
     let mut buckets_frozen = ~[];
     for buckets.each |bucket| {
-        buckets_frozen.push(@**bucket);
+        buckets_frozen.push(@/*bad*/copy **bucket);
     }
     return buckets_frozen;
 }
@@ -969,7 +991,7 @@ fn encode_meta_item(ebml_w: writer::Encoder, mi: meta_item) {
           _ => {/* FIXME (#623): encode other variants */ }
         }
       }
-      meta_list(ref name, items) => {
+      meta_list(ref name, ref items) => {
         ebml_w.start_tag(tag_meta_item_list);
         ebml_w.start_tag(tag_meta_item_name);
         ebml_w.writer.write(str::to_bytes((*name)));
@@ -998,16 +1020,18 @@ fn encode_attributes(ebml_w: writer::Encoder, attrs: ~[attribute]) {
 // them in anyway with default values.
 fn synthesize_crate_attrs(ecx: @encode_ctxt, crate: @crate) -> ~[attribute] {
 
-    fn synthesize_link_attr(ecx: @encode_ctxt, items: ~[@meta_item]) ->
+    fn synthesize_link_attr(ecx: @encode_ctxt, +items: ~[@meta_item]) ->
        attribute {
 
         assert (ecx.link_meta.name != ~"");
         assert (ecx.link_meta.vers != ~"");
 
         let name_item =
-            attr::mk_name_value_item_str(~"name", ecx.link_meta.name);
+            attr::mk_name_value_item_str(~"name",
+                                         /*bad*/copy ecx.link_meta.name);
         let vers_item =
-            attr::mk_name_value_item_str(~"vers", ecx.link_meta.vers);
+            attr::mk_name_value_item_str(~"vers",
+                                         /*bad*/copy ecx.link_meta.vers);
 
         let other_items =
             {
@@ -1026,14 +1050,14 @@ fn synthesize_crate_attrs(ecx: @encode_ctxt, crate: @crate) -> ~[attribute] {
     for crate.node.attrs.each |attr| {
         attrs.push(
             if attr::get_attr_name(*attr) != ~"link" {
-                *attr
+                /*bad*/copy *attr
             } else {
-                match attr.node.value.node {
+                match /*bad*/copy attr.node.value.node {
                   meta_list(_, l) => {
                     found_link_attr = true;;
                     synthesize_link_attr(ecx, l)
                   }
-                  _ => *attr
+                  _ => /*bad*/copy *attr
                 }
             });
     }
@@ -1055,7 +1079,8 @@ fn encode_crate_deps(ecx: @encode_ctxt, ebml_w: writer::Encoder,
         // Pull the cnums and name,vers,hash out of cstore
         let mut deps: ~[numdep] = ~[];
         do cstore::iter_crate_data(cstore) |key, val| {
-            let dep = {cnum: key, name: ecx.tcx.sess.ident_of(val.name),
+            let dep = {cnum: key,
+                       name: ecx.tcx.sess.ident_of(/*bad*/copy val.name),
                        vers: decoder::get_crate_vers(val.data),
                        hash: decoder::get_crate_hash(val.data)};
             deps.push(dep);
@@ -1161,7 +1186,7 @@ fn encode_metadata(parms: encode_parms, crate: @crate) -> ~[u8] {
         reexports2: parms.reexports2,
         item_symbols: parms.item_symbols,
         discrim_symbols: parms.discrim_symbols,
-        link_meta: parms.link_meta,
+        link_meta: /*bad*/copy parms.link_meta,
         cstore: parms.cstore,
         encode_inlined_item: parms.encode_inlined_item,
         type_abbrevs: ty::new_ty_hash()
@@ -1169,7 +1194,7 @@ fn encode_metadata(parms: encode_parms, crate: @crate) -> ~[u8] {
 
     let ebml_w = writer::Encoder(wr as io::Writer);
 
-    encode_hash(ebml_w, ecx.link_meta.extras_hash);
+    encode_hash(ebml_w, /*bad*/copy ecx.link_meta.extras_hash);
 
     let mut i = wr.pos;
     let crate_attrs = synthesize_crate_attrs(ecx, crate);
diff --git a/src/librustc/metadata/filesearch.rs b/src/librustc/metadata/filesearch.rs
index 849d56958c3..0401d8fcb6c 100644
--- a/src/librustc/metadata/filesearch.rs
+++ b/src/librustc/metadata/filesearch.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // A module for searching for libraries
 // FIXME (#2658): I'm not happy how this module turned out. Should
 // probably just be folded into cstore.
@@ -45,24 +46,24 @@ trait FileSearch {
 
 fn mk_filesearch(maybe_sysroot: Option<Path>,
                  target_triple: &str,
-                 addl_lib_search_paths: ~[Path]) -> FileSearch {
+                 +addl_lib_search_paths: ~[Path]) -> FileSearch {
     type filesearch_impl = {sysroot: Path,
                             addl_lib_search_paths: ~[Path],
                             target_triple: ~str};
     impl filesearch_impl: FileSearch {
-        fn sysroot() -> Path { self.sysroot }
+        fn sysroot() -> Path { /*bad*/copy self.sysroot }
         fn lib_search_paths() -> ~[Path] {
-            let mut paths = self.addl_lib_search_paths;
+            let mut paths = /*bad*/copy self.addl_lib_search_paths;
 
             paths.push(
                 make_target_lib_path(&self.sysroot,
                                      self.target_triple));
             match get_cargo_lib_path_nearest() {
-              result::Ok(ref p) => paths.push((*p)),
+              result::Ok(ref p) => paths.push((/*bad*/copy *p)),
               result::Err(_) => ()
             }
             match get_cargo_lib_path() {
-              result::Ok(ref p) => paths.push((*p)),
+              result::Ok(ref p) => paths.push((/*bad*/copy *p)),
               result::Err(_) => ()
             }
             paths
@@ -122,7 +123,7 @@ fn get_or_default_sysroot() -> Path {
 
 fn get_sysroot(maybe_sysroot: Option<Path>) -> Path {
     match maybe_sysroot {
-      option::Some(ref sr) => (*sr),
+      option::Some(ref sr) => (/*bad*/copy *sr),
       option::None => get_or_default_sysroot()
     }
 }
@@ -146,7 +147,7 @@ fn get_cargo_root_nearest() -> Result<Path, ~str> {
         let cwd = os::getcwd();
         let cwd_cargo = cwd.push(".cargo");
         let mut par_cargo = cwd.pop().push(".cargo");
-        let mut rslt = result::Ok(cwd_cargo);
+        let mut rslt = result::Ok(copy cwd_cargo);  // XXX: Bad copy.
 
         if !os::path_is_dir(&cwd_cargo) && cwd_cargo != p {
             while par_cargo != p {
diff --git a/src/librustc/metadata/loader.rs b/src/librustc/metadata/loader.rs
index e75329340c2..818b93545cf 100644
--- a/src/librustc/metadata/loader.rs
+++ b/src/librustc/metadata/loader.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 //! Finds crate binaries and loads their metadata
 
 use lib::llvm::{False, llvm, mk_object_file, mk_section_iter};
@@ -62,7 +63,7 @@ type ctxt = {
 
 fn load_library_crate(cx: ctxt) -> {ident: ~str, data: @~[u8]} {
     match find_library_crate(cx) {
-      Some(ref t) => return (*t),
+      Some(ref t) => return (/*bad*/copy *t),
       None => {
         cx.diag.span_fatal(
             cx.span, fmt!("can't find crate for `%s`",
@@ -72,7 +73,7 @@ fn load_library_crate(cx: ctxt) -> {ident: ~str, data: @~[u8]} {
 }
 
 fn find_library_crate(cx: ctxt) -> Option<{ident: ~str, data: @~[u8]}> {
-    attr::require_unique_names(cx.diag, cx.metas);
+    attr::require_unique_names(cx.diag, /*bad*/copy cx.metas);
     find_library_crate_aux(cx, libname(cx), cx.filesearch)
 }
 
@@ -90,9 +91,9 @@ fn find_library_crate_aux(cx: ctxt,
                           nn: {prefix: ~str, suffix: ~str},
                           filesearch: filesearch::FileSearch) ->
    Option<{ident: ~str, data: @~[u8]}> {
-    let crate_name = crate_name_from_metas(cx.metas);
+    let crate_name = crate_name_from_metas(/*bad*/copy cx.metas);
     let prefix: ~str = nn.prefix + crate_name + ~"-";
-    let suffix: ~str = nn.suffix;
+    let suffix: ~str = /*bad*/copy nn.suffix;
 
     let mut matches = ~[];
     filesearch::search(filesearch, |path| {
@@ -127,7 +128,7 @@ fn find_library_crate_aux(cx: ctxt,
     if matches.is_empty() {
         None
     } else if matches.len() == 1u {
-        Some(matches[0])
+        Some(/*bad*/copy matches[0])
     } else {
         cx.diag.span_err(
             cx.span, fmt!("multiple matching crates for `%s`", crate_name));
@@ -142,12 +143,12 @@ fn find_library_crate_aux(cx: ctxt,
     }
 }
 
-fn crate_name_from_metas(metas: ~[@ast::meta_item]) -> ~str {
+fn crate_name_from_metas(+metas: ~[@ast::meta_item]) -> ~str {
     let name_items = attr::find_meta_items_by_name(metas, ~"name");
     match vec::last_opt(name_items) {
       Some(i) => {
         match attr::get_meta_item_value_str(i) {
-          Some(ref n) => (*n),
+          Some(ref n) => (/*bad*/copy *n),
           // FIXME (#2406): Probably want a warning here since the user
           // is using the wrong type of meta item.
           _ => fail
@@ -165,7 +166,7 @@ fn note_linkage_attrs(intr: @ident_interner, diag: span_handler,
     }
 }
 
-fn crate_matches(crate_data: @~[u8], metas: ~[@ast::meta_item],
+fn crate_matches(crate_data: @~[u8], +metas: ~[@ast::meta_item],
                  hash: ~str) -> bool {
     let attrs = decoder::get_crate_attributes(crate_data);
     let linkage_metas = attr::find_linkage_metas(attrs);
diff --git a/src/librustc/metadata/mod.rs b/src/librustc/metadata/mod.rs
index 4ba6abb0383..25a73b009a9 100644
--- a/src/librustc/metadata/mod.rs
+++ b/src/librustc/metadata/mod.rs
@@ -9,6 +9,7 @@
 // except according to those terms.
 
 #[legacy_exports];
+
 export encoder;
 export creader;
 export cstore;
diff --git a/src/librustc/metadata/tydecode.rs b/src/librustc/metadata/tydecode.rs
index 8c4eba2b75e..38bfaa98566 100644
--- a/src/librustc/metadata/tydecode.rs
+++ b/src/librustc/metadata/tydecode.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // Type decoding
 
 // tjc note: Would be great to have a `match check` macro equivalent
diff --git a/src/librustc/metadata/tyencode.rs b/src/librustc/metadata/tyencode.rs
index 07838bcb1aa..cf1a7db07a5 100644
--- a/src/librustc/metadata/tyencode.rs
+++ b/src/librustc/metadata/tyencode.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // Type encoding
 
 use middle::ty;
@@ -60,12 +61,12 @@ fn enc_ty(w: io::Writer, cx: @ctxt, t: ty::t) {
     match cx.abbrevs {
       ac_no_abbrevs => {
         let result_str = match cx.tcx.short_names_cache.find(t) {
-            Some(s) => *s,
+            Some(s) => /*bad*/copy *s,
             None => {
                 let s = do io::with_str_writer |wr| {
-                    enc_sty(wr, cx, ty::get(t).sty);
+                    enc_sty(wr, cx, /*bad*/copy ty::get(t).sty);
                 };
-                cx.tcx.short_names_cache.insert(t, @s);
+                cx.tcx.short_names_cache.insert(t, @copy s);
                 s
           }
         };
@@ -89,7 +90,7 @@ fn enc_ty(w: io::Writer, cx: @ctxt, t: ty::t) {
               }
               _ => {}
             }
-            enc_sty(w, cx, ty::get(t).sty);
+            enc_sty(w, cx, /*bad*/copy ty::get(t).sty);
             let end = w.tell();
             let len = end - pos;
             fn estimate_sz(u: uint) -> uint {
@@ -210,7 +211,7 @@ fn enc_vstore(w: io::Writer, cx: @ctxt, v: ty::vstore) {
     }
 }
 
-fn enc_sty(w: io::Writer, cx: @ctxt, st: ty::sty) {
+fn enc_sty(w: io::Writer, cx: @ctxt, +st: ty::sty) {
     match st {
       ty::ty_nil => w.write_char('n'),
       ty::ty_bot => w.write_char('z'),
diff --git a/src/librustc/middle/astencode.rs b/src/librustc/middle/astencode.rs
index 3a308011e75..f6208d3b1dd 100644
--- a/src/librustc/middle/astencode.rs
+++ b/src/librustc/middle/astencode.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use c = metadata::common;
 use cstore = metadata::cstore;
 use driver::session::Session;
@@ -113,7 +114,7 @@ fn encode_inlined_item(ecx: @e::encode_ctxt,
 fn decode_inlined_item(cdata: cstore::crate_metadata,
                        tcx: ty::ctxt,
                        maps: maps,
-                       path: ast_map::path,
+                       +path: ast_map::path,
                        par_doc: ebml::Doc) -> Option<ast::inlined_item> {
     let dcx = @{cdata: cdata, tcx: tcx, maps: maps};
     match par_doc.opt_child(c::tag_ast) {
@@ -129,8 +130,9 @@ fn decode_inlined_item(cdata: cstore::crate_metadata,
                                           to_id_range: to_id_range});
         let raw_ii = decode_ast(ast_doc);
         let ii = renumber_ast(xcx, raw_ii);
+        // XXX: Bad copy of `path`.
         ast_map::map_decoded_item(tcx.sess.diagnostic(),
-                                  dcx.tcx.items, path, ii);
+                                  dcx.tcx.items, copy path, ii);
         debug!("Fn named: %s", tcx.sess.str_of(ii.ident()));
         decode_side_tables(xcx, ast_doc);
         debug!("< Decoded inlined fn: %s::%s",
@@ -261,7 +263,8 @@ fn simplify_ast(ii: ast::inlined_item) -> ast::inlined_item {
               ast::stmt_mac(*) => fail ~"unexpanded macro in astencode"
             }
         };
-        let blk_sans_items = { stmts: stmts_sans_items,.. blk };
+        // XXX: Bad copy.
+        let blk_sans_items = { stmts: stmts_sans_items,.. copy blk };
         fold::noop_fold_block(blk_sans_items, fld)
     }
 
@@ -280,11 +283,11 @@ fn simplify_ast(ii: ast::inlined_item) -> ast::inlined_item {
       ast::ii_foreign(i) => {
         ast::ii_foreign(fld.fold_foreign_item(i))
       }
-      ast::ii_dtor(ref dtor, nm, tps, parent_id) => {
+      ast::ii_dtor(ref dtor, nm, ref tps, parent_id) => {
         let dtor_body = fld.fold_block((*dtor).node.body);
         ast::ii_dtor({node: {body: dtor_body,
-                              .. (*dtor).node},
-            .. (*dtor)}, nm, tps, parent_id)
+                              .. /*bad*/copy (*dtor).node},
+            .. (/*bad*/copy *dtor)}, nm, /*bad*/copy *tps, parent_id)
       }
     }
 }
@@ -313,16 +316,16 @@ fn renumber_ast(xcx: extended_decode_ctxt, ii: ast::inlined_item)
       ast::ii_foreign(i) => {
         ast::ii_foreign(fld.fold_foreign_item(i))
       }
-      ast::ii_dtor(ref dtor, nm, tps, parent_id) => {
+      ast::ii_dtor(ref dtor, nm, ref tps, parent_id) => {
         let dtor_body = fld.fold_block((*dtor).node.body);
-        let dtor_attrs = fld.fold_attributes((*dtor).node.attrs);
-        let new_params = fold::fold_ty_params(tps, fld);
+        let dtor_attrs = fld.fold_attributes(/*bad*/copy (*dtor).node.attrs);
+        let new_params = fold::fold_ty_params(/*bad*/copy *tps, fld);
         let dtor_id = fld.new_id((*dtor).node.id);
         let new_parent = xcx.tr_def_id(parent_id);
         let new_self = fld.new_id((*dtor).node.self_id);
         ast::ii_dtor({node: {id: dtor_id, attrs: dtor_attrs,
                 self_id: new_self, body: dtor_body},
-                        .. (*dtor)},
+                        .. (/*bad*/copy *dtor)},
           nm, new_params, new_parent)
       }
      }
@@ -520,7 +523,7 @@ fn encode_vtable_res(ecx: @e::encode_ctxt,
     // ty::t doesn't work, and there is no way (atm) to have
     // hand-written encoding routines combine with auto-generated
     // ones.  perhaps we should fix this.
-    do ebml_w.emit_from_vec(*dr) |vtable_origin| {
+    do ebml_w.emit_from_vec(/*bad*/copy *dr) |vtable_origin| {
         encode_vtable_origin(ecx, ebml_w, *vtable_origin)
     }
 }
@@ -529,14 +532,14 @@ fn encode_vtable_origin(ecx: @e::encode_ctxt,
                       ebml_w: writer::Encoder,
                       vtable_origin: typeck::vtable_origin) {
     do ebml_w.emit_enum(~"vtable_origin") {
-        match vtable_origin {
+        match /*bad*/copy vtable_origin {
           typeck::vtable_static(def_id, tys, vtable_res) => {
             do ebml_w.emit_enum_variant(~"vtable_static", 0u, 3u) {
                 do ebml_w.emit_enum_variant_arg(0u) {
                     ebml_w.emit_def_id(def_id)
                 }
                 do ebml_w.emit_enum_variant_arg(1u) {
-                    ebml_w.emit_tys(ecx, tys);
+                    ebml_w.emit_tys(ecx, /*bad*/copy tys);
                 }
                 do ebml_w.emit_enum_variant_arg(2u) {
                     encode_vtable_res(ecx, ebml_w, vtable_res);
@@ -559,7 +562,7 @@ fn encode_vtable_origin(ecx: @e::encode_ctxt,
                     ebml_w.emit_def_id(def_id)
                 }
                 do ebml_w.emit_enum_variant_arg(1u) {
-                    ebml_w.emit_tys(ecx, tys);
+                    ebml_w.emit_tys(ecx, /*bad*/copy tys);
                 }
             }
           }
@@ -670,7 +673,8 @@ impl writer::Encoder: ebml_writer_helpers {
     }
 
     fn emit_tys(ecx: @e::encode_ctxt, tys: ~[ty::t]) {
-        do self.emit_from_vec(tys) |ty| {
+        // XXX: Bad copy.
+        do self.emit_from_vec(copy tys) |ty| {
             self.emit_ty(ecx, *ty)
         }
     }
@@ -684,7 +688,7 @@ impl writer::Encoder: ebml_writer_helpers {
     fn emit_tpbt(ecx: @e::encode_ctxt, tpbt: ty::ty_param_bounds_and_ty) {
         do self.emit_rec {
             do self.emit_field(~"bounds", 0u) {
-                do self.emit_from_vec(*tpbt.bounds) |bs| {
+                do self.emit_from_vec(/*bad*/copy *tpbt.bounds) |bs| {
                     self.emit_bounds(ecx, *bs);
                 }
             }
@@ -758,7 +762,7 @@ fn encode_side_tables_for_id(ecx: @e::encode_ctxt,
         do ebml_w.tag(c::tag_table_node_type_subst) {
             ebml_w.id(id);
             do ebml_w.tag(c::tag_table_val) {
-                ebml_w.emit_tys(ecx, *tys)
+                ebml_w.emit_tys(ecx, /*bad*/copy *tys)
             }
         }
     }
@@ -767,7 +771,7 @@ fn encode_side_tables_for_id(ecx: @e::encode_ctxt,
         do ebml_w.tag(c::tag_table_freevars) {
             ebml_w.id(id);
             do ebml_w.tag(c::tag_table_val) {
-                do ebml_w.emit_from_vec(**fv) |fv_entry| {
+                do ebml_w.emit_from_vec(/*bad*/copy **fv) |fv_entry| {
                     encode_freevar_entry(ebml_w, *fv_entry)
                 }
             }
diff --git a/src/librustc/middle/borrowck/check_loans.rs b/src/librustc/middle/borrowck/check_loans.rs
index 43a2c6edaba..4370707e665 100644
--- a/src/librustc/middle/borrowck/check_loans.rs
+++ b/src/librustc/middle/borrowck/check_loans.rs
@@ -17,6 +17,7 @@
 // 3. assignments do not affect things loaned out as immutable
 // 4. moves to dnot affect things loaned out in any way
 
+
 use middle::ty::{CopyValue, MoveValue, ReadValue};
 use middle::ty;
 
@@ -631,7 +632,7 @@ fn check_loans_in_expr(expr: @ast::expr,
         Some(ReadValue) | Some(CopyValue) | None => {}
     }
 
-    match expr.node {
+    match /*bad*/copy expr.node {
       ast::expr_path(*) if self.bccx.last_use_map.contains_key(expr.id) => {
         self.check_last_use(expr);
       }
diff --git a/src/librustc/middle/borrowck/gather_loans.rs b/src/librustc/middle/borrowck/gather_loans.rs
index 8cff25640cb..9524980a1f9 100644
--- a/src/librustc/middle/borrowck/gather_loans.rs
+++ b/src/librustc/middle/borrowck/gather_loans.rs
@@ -16,6 +16,7 @@
 // their associated scopes.  In phase two, checking loans, we will then make
 // sure that all of these loans are honored.
 
+
 use middle::borrowck::preserve::{preserve_condition, pc_ok, pc_if_pure};
 use middle::mem_categorization::{mem_categorization_ctxt, opt_deref_kind};
 use middle::pat_util;
@@ -122,7 +123,7 @@ fn req_loans_in_expr(ex: @ast::expr,
     }
 
     // Special checks for various kinds of expressions:
-    match ex.node {
+    match /*bad*/copy ex.node {
       ast::expr_addr_of(mutbl, base) => {
         let base_cmt = self.bccx.cat_expr(base);
 
diff --git a/src/librustc/middle/borrowck/loan.rs b/src/librustc/middle/borrowck/loan.rs
index c79a733e92d..6539cb0c6c3 100644
--- a/src/librustc/middle/borrowck/loan.rs
+++ b/src/librustc/middle/borrowck/loan.rs
@@ -12,6 +12,7 @@
 // Loan(Ex, M, S) = Ls holds if ToAddr(Ex) will remain valid for the entirety
 // of the scope S, presuming that the returned set of loans `Ls` are honored.
 
+
 use middle::ty;
 
 use core::result::{Result, Ok, Err};
diff --git a/src/librustc/middle/borrowck/mod.rs b/src/librustc/middle/borrowck/mod.rs
index 19b22931a1c..1cd88aa8197 100644
--- a/src/librustc/middle/borrowck/mod.rs
+++ b/src/librustc/middle/borrowck/mod.rs
@@ -519,11 +519,11 @@ impl borrowck_ctxt {
         self.note_and_explain_bckerr(err);
     }
 
-    fn span_err(s: span, m: ~str) {
+    fn span_err(s: span, +m: ~str) {
         self.tcx.sess.span_err(s, m);
     }
 
-    fn span_note(s: span, m: ~str) {
+    fn span_note(s: span, +m: ~str) {
         self.tcx.sess.span_note(s, m);
     }
 
diff --git a/src/librustc/middle/borrowck/preserve.rs b/src/librustc/middle/borrowck/preserve.rs
index af2832cf11e..220685e58ca 100644
--- a/src/librustc/middle/borrowck/preserve.rs
+++ b/src/librustc/middle/borrowck/preserve.rs
@@ -13,6 +13,7 @@
 // the scope S.
 //
 
+
 use middle::ty;
 
 use syntax::ast;
diff --git a/src/librustc/middle/capture.rs b/src/librustc/middle/capture.rs
index 8a498c1935b..86d9151ae9b 100644
--- a/src/librustc/middle/capture.rs
+++ b/src/librustc/middle/capture.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::freevars;
 use middle::ty;
 
diff --git a/src/librustc/middle/check_alt.rs b/src/librustc/middle/check_alt.rs
index e87d83c9c15..bdd2b06e6ab 100644
--- a/src/librustc/middle/check_alt.rs
+++ b/src/librustc/middle/check_alt.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::const_eval::{compare_const_vals, lookup_const_by_id};
 use middle::const_eval::{eval_const_expr, const_val, const_int, const_bool};
 use middle::pat_util::*;
@@ -73,7 +74,7 @@ fn check_expr(cx: @AltCheckCtxt, ex: @expr, &&s: (), v: visit::vt<()>) {
                                             arm.pats);
         }
 
-        check_arms(cx, (*arms));
+        check_arms(cx, (/*bad*/copy *arms));
         /* Check for exhaustiveness */
          // Check for empty enum, because is_useful only works on inhabited
          // types.
@@ -215,7 +216,7 @@ impl ctor : cmp::Eq {
 
 // Note: is_useful doesn't work on empty types, as the paper notes.
 // So it assumes that v is non-empty.
-fn is_useful(cx: @AltCheckCtxt, m: matrix, v: ~[@pat]) -> useful {
+fn is_useful(cx: @AltCheckCtxt, +m: matrix, +v: ~[@pat]) -> useful {
     if m.len() == 0u { return useful_; }
     if m[0].len() == 0u { return not_useful; }
     let real_pat = match vec::find(m, |r| r[0].id != 0) {
@@ -238,7 +239,7 @@ fn is_useful(cx: @AltCheckCtxt, m: matrix, v: ~[@pat]) -> useful {
                                           val(const_bool(false)),
                                           0u, left_ty)
                   }
-                  ref u => (*u)
+                  ref u => (/*bad*/copy *u)
                 }
               }
               ty::ty_enum(eid, _) => {
@@ -246,14 +247,14 @@ fn is_useful(cx: @AltCheckCtxt, m: matrix, v: ~[@pat]) -> useful {
                     match is_useful_specialized(cx, m, v, variant(va.id),
                                                 va.args.len(), left_ty) {
                       not_useful => (),
-                      ref u => return (*u)
+                      ref u => return (/*bad*/copy *u)
                     }
                 }
                 not_useful
               }
               ty::ty_unboxed_vec(*) | ty::ty_evec(*) => {
                 let max_len = do m.foldr(0) |r, max_len| {
-                  match r[0].node {
+                  match /*bad*/copy r[0].node {
                     pat_vec(elems, _) => uint::max(elems.len(), max_len),
                     _ => max_len
                   }
@@ -261,7 +262,7 @@ fn is_useful(cx: @AltCheckCtxt, m: matrix, v: ~[@pat]) -> useful {
                 for uint::range(0, max_len + 1) |n| {
                   match is_useful_specialized(cx, m, v, vec(n), n, left_ty) {
                     not_useful => (),
-                    ref u => return (*u)
+                    ref u => return (/*bad*/copy *u)
                   }
                 }
                 not_useful
@@ -275,33 +276,33 @@ fn is_useful(cx: @AltCheckCtxt, m: matrix, v: ~[@pat]) -> useful {
           Some(ref ctor) => {
             match is_useful(cx, vec::filter_map(m, |r| default(cx, *r)),
                             vec::tail(v)) {
-              useful_ => useful(left_ty, (*ctor)),
-              ref u => (*u)
+              useful_ => useful(left_ty, (/*bad*/copy *ctor)),
+              ref u => (/*bad*/copy *u)
             }
           }
         }
       }
       Some(ref v0_ctor) => {
         let arity = ctor_arity(cx, (*v0_ctor), left_ty);
-        is_useful_specialized(cx, m, v, (*v0_ctor), arity, left_ty)
+        is_useful_specialized(cx, m, v, /*bad*/copy *v0_ctor, arity, left_ty)
       }
     }
 }
 
-fn is_useful_specialized(cx: @AltCheckCtxt, m: matrix, v: ~[@pat], ctor: ctor,
-                          arity: uint, lty: ty::t) -> useful {
+fn is_useful_specialized(cx: @AltCheckCtxt, m: matrix, +v: ~[@pat],
+                         +ctor: ctor, arity: uint, lty: ty::t) -> useful {
     let ms = vec::filter_map(m, |r| specialize(cx, *r, ctor, arity, lty));
     let could_be_useful = is_useful(
         cx, ms, specialize(cx, v, ctor, arity, lty).get());
     match could_be_useful {
       useful_ => useful(lty, ctor),
-      ref u => (*u)
+      ref u => (/*bad*/copy *u)
     }
 }
 
 fn pat_ctor_id(cx: @AltCheckCtxt, p: @pat) -> Option<ctor> {
     let pat = raw_pat(p);
-    match pat.node {
+    match /*bad*/copy pat.node {
       pat_wild => { None }
       pat_ident(_, _, _) | pat_enum(_, _) => {
         match cx.tcx.def_map.find(pat.id) {
@@ -367,7 +368,7 @@ fn missing_ctor(cx: @AltCheckCtxt,
         for m.each |r| {
             do option::iter(&pat_ctor_id(cx, r[0])) |id| {
                 if !vec::contains(found, id) {
-                    found.push(*id);
+                    found.push(/*bad*/copy *id);
                 }
             }
         }
@@ -400,7 +401,7 @@ fn missing_ctor(cx: @AltCheckCtxt,
 
         // Find the lengths and tails of all vector patterns.
         let vec_pat_lens = do m.filter_map |r| {
-            match r[0].node {
+            match /*bad*/copy r[0].node {
                 pat_vec(elems, tail) => {
                     Some((elems.len(), tail.is_some()))
                 }
@@ -451,7 +452,7 @@ fn missing_ctor(cx: @AltCheckCtxt,
 }
 
 fn ctor_arity(cx: @AltCheckCtxt, ctor: ctor, ty: ty::t) -> uint {
-    match ty::get(ty).sty {
+    match /*bad*/copy ty::get(ty).sty {
       ty::ty_tup(fs) => fs.len(),
       ty::ty_rec(fs) => fs.len(),
       ty::ty_box(_) | ty::ty_uniq(_) | ty::ty_rptr(*) => 1u,
@@ -481,7 +482,7 @@ fn wild() -> @pat {
 fn specialize(cx: @AltCheckCtxt, r: ~[@pat], ctor_id: ctor, arity: uint,
               left_ty: ty::t) -> Option<~[@pat]> {
     let r0 = raw_pat(r[0]);
-    match r0.node {
+    match /*bad*/copy r0.node {
       pat_wild => Some(vec::append(vec::from_elem(arity, wild()),
                                    vec::tail(r))),
       pat_ident(_, _, _) => {
@@ -530,7 +531,7 @@ fn specialize(cx: @AltCheckCtxt, r: ~[@pat], ctor_id: ctor, arity: uint,
         }
       }
       pat_rec(flds, _) => {
-        let ty_flds = match ty::get(left_ty).sty {
+        let ty_flds = match /*bad*/copy ty::get(left_ty).sty {
             ty::ty_rec(flds) => flds,
             _ => fail ~"bad type for pat_rec"
         };
@@ -602,8 +603,8 @@ fn specialize(cx: @AltCheckCtxt, r: ~[@pat], ctor_id: ctor, arity: uint,
       }
       pat_range(lo, hi) => {
         let (c_lo, c_hi) = match ctor_id {
-          val(ref v) => ((*v), (*v)),
-          range(ref lo, ref hi) => ((*lo), (*hi)),
+          val(ref v) => ((/*bad*/copy *v), (/*bad*/copy *v)),
+          range(ref lo, ref hi) => ((/*bad*/copy *lo), (/*bad*/copy *hi)),
           single => return Some(vec::tail(r)),
           _ => fail ~"type error"
         };
@@ -617,8 +618,9 @@ fn specialize(cx: @AltCheckCtxt, r: ~[@pat], ctor_id: ctor, arity: uint,
         match ctor_id {
           vec(_) => {
             if elems.len() < arity && tail.is_some() {
+              // XXX: Bad copy.
               Some(vec::append(
-                vec::append(elems, vec::from_elem(
+                vec::append(copy elems, vec::from_elem(
                     arity - elems.len(), wild()
                 )),
                 vec::tail(r)
@@ -683,7 +685,7 @@ fn is_refutable(cx: @AltCheckCtxt, pat: &pat) -> bool {
       _ => ()
     }
 
-    match pat.node {
+    match /*bad*/copy pat.node {
       pat_box(sub) | pat_uniq(sub) | pat_region(sub) |
       pat_ident(_, _, Some(sub)) => {
         is_refutable(cx, sub)
diff --git a/src/librustc/middle/check_const.rs b/src/librustc/middle/check_const.rs
index f7fa5c60b2f..13df0b73db0 100644
--- a/src/librustc/middle/check_const.rs
+++ b/src/librustc/middle/check_const.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use driver::session::Session;
 use middle::resolve;
 use middle::ty;
diff --git a/src/librustc/middle/check_loop.rs b/src/librustc/middle/check_loop.rs
index d96d29f6835..88443843270 100644
--- a/src/librustc/middle/check_loop.rs
+++ b/src/librustc/middle/check_loop.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 
 use syntax::ast::*;
diff --git a/src/librustc/middle/const_eval.rs b/src/librustc/middle/const_eval.rs
index ec498c18d89..dbde060c6f5 100644
--- a/src/librustc/middle/const_eval.rs
+++ b/src/librustc/middle/const_eval.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::resolve;
 use middle::ty;
 use middle;
@@ -79,7 +80,7 @@ fn classify(e: @expr,
       Some(x) => x,
       None => {
         let cn =
-            match e.node {
+            match /*bad*/copy e.node {
               ast::expr_lit(lit) => {
                 match lit.node {
                   ast::lit_str(*) |
@@ -241,8 +242,8 @@ impl const_val : cmp::Eq {
 
 fn eval_const_expr(tcx: middle::ty::ctxt, e: @expr) -> const_val {
     match eval_const_expr_partial(tcx, e) {
-        Ok(ref r) => (*r),
-        Err(ref s) => fail (*s)
+        Ok(ref r) => (/*bad*/copy *r),
+        Err(ref s) => fail (/*bad*/copy *s)
     }
 }
 
@@ -258,7 +259,7 @@ fn eval_const_expr_partial(tcx: middle::ty::ctxt, e: @expr)
           Ok(const_uint(i)) => Ok(const_uint(-i)),
           Ok(const_str(_)) => Err(~"Negate on string"),
           Ok(const_bool(_)) => Err(~"Negate on boolean"),
-          ref err => (*err)
+          ref err => (/*bad*/copy *err)
         }
       }
       expr_unary(not, inner) => {
@@ -405,7 +406,7 @@ fn eval_const_expr_partial(tcx: middle::ty::ctxt, e: @expr)
 
 fn lit_to_const(lit: @lit) -> const_val {
     match lit.node {
-      lit_str(s) => const_str(*s),
+      lit_str(s) => const_str(/*bad*/copy *s),
       lit_int(n, _) => const_int(n),
       lit_uint(n, _) => const_uint(n),
       lit_int_unsuffixed(n) => const_int(n),
diff --git a/src/librustc/middle/freevars.rs b/src/librustc/middle/freevars.rs
index 3cd82a8ed2a..9b718ec3bee 100644
--- a/src/librustc/middle/freevars.rs
+++ b/src/librustc/middle/freevars.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // A pass that annotates for each loops and functions with the free
 // variables that they contain.
 
@@ -92,7 +93,7 @@ fn collect_freevars(def_map: resolve::DefMap, blk: ast::blk)
     let v = visit::mk_vt(@{visit_item: ignore_item, visit_expr: walk_expr,
                            .. *visit::default_visitor()});
     (v.visit_block)(blk, 1, v);
-    return @*refs;
+    return @/*bad*/copy *refs;
 }
 
 // Build a map from every function and for-each body to a set of the
diff --git a/src/librustc/middle/kind.rs b/src/librustc/middle/kind.rs
index 36a1fe62c58..671a0a2dc81 100644
--- a/src/librustc/middle/kind.rs
+++ b/src/librustc/middle/kind.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::freevars::freevar_entry;
 use middle::freevars;
 use middle::lint::{non_implicitly_copyable_typarams, implicit_copies};
@@ -296,7 +297,7 @@ fn check_expr(e: @expr, cx: ctx, v: visit::vt<ctx>) {
         }
     }
 
-    match e.node {
+    match /*bad*/copy e.node {
       expr_assign(_, ex) |
       expr_unary(box(_), ex) | expr_unary(uniq(_), ex) |
       expr_ret(Some(ex)) => {
@@ -329,7 +330,7 @@ fn check_expr(e: @expr, cx: ctx, v: visit::vt<ctx>) {
           Some(ex) => {
             // All noncopyable fields must be overridden
             let t = ty::expr_ty(cx.tcx, ex);
-            let ty_fields = match ty::get(t).sty {
+            let ty_fields = match /*bad*/copy ty::get(t).sty {
               ty::ty_rec(f) => f,
               ty::ty_struct(did, ref substs) =>
                   ty::struct_fields(cx.tcx, did, &(*substs)),
@@ -407,7 +408,7 @@ fn check_expr(e: @expr, cx: ctx, v: visit::vt<ctx>) {
 
 fn check_stmt(stmt: @stmt, cx: ctx, v: visit::vt<ctx>) {
     match stmt.node {
-      stmt_decl(@{node: decl_local(locals), _}, _) => {
+      stmt_decl(@{node: decl_local(ref locals), _}, _) => {
         for locals.each |local| {
             match local.node.init {
               Some(expr) =>
@@ -614,7 +615,7 @@ fn check_cast_for_escaping_regions(
     // worries.
     let target_ty = ty::expr_ty(cx.tcx, target);
     let target_substs = match ty::get(target_ty).sty {
-      ty::ty_trait(_, ref substs, _) => {(*substs)}
+      ty::ty_trait(_, ref substs, _) => {(/*bad*/copy *substs)}
       _ => { return; /* not a cast to a trait */ }
     };
 
diff --git a/src/librustc/middle/lang_items.rs b/src/librustc/middle/lang_items.rs
index ec01b79c37e..8c887139b70 100644
--- a/src/librustc/middle/lang_items.rs
+++ b/src/librustc/middle/lang_items.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // Detecting language items.
 //
 // Language items are items that represent concepts intrinsic to the language
@@ -287,8 +288,8 @@ impl LanguageItemCollector {
                 match literal.node {
                     lit_str(value) => {
                         self.match_and_collect_item(item_def_id,
-                                                    (*key),
-                                                    *value);
+                                                    (/*bad*/copy *key),
+                                                    /*bad*/copy *value);
                     }
                     _ => {} // Skip.
                 }
diff --git a/src/librustc/middle/lint.rs b/src/librustc/middle/lint.rs
index f7c2503df7c..77a63b18778 100644
--- a/src/librustc/middle/lint.rs
+++ b/src/librustc/middle/lint.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use driver::session::Session;
 use driver::session;
 use middle::pat_util::{pat_bindings};
@@ -310,7 +311,7 @@ impl ctxt {
         }
     }
 
-    fn span_lint(level: level, span: span, msg: ~str) {
+    fn span_lint(level: level, span: span, +msg: ~str) {
         self.sess.span_lint_level(level, span, msg);
     }
 
@@ -327,15 +328,17 @@ impl ctxt {
         for [allow, warn, deny, forbid].each |level| {
             let level_name = level_to_str(*level);
             let metas =
-                attr::attr_metas(attr::find_attrs_by_name(attrs,
+                attr::attr_metas(attr::find_attrs_by_name(/*bad*/copy attrs,
                                                           level_name));
             for metas.each |meta| {
-                match meta.node {
+                match /*bad*/copy meta.node {
                   ast::meta_list(_, metas) => {
                     for metas.each |meta| {
                         match meta.node {
                           ast::meta_word(ref lintname) => {
-                            triples.push((*meta, *level, *lintname));
+                            triples.push((*meta,
+                                          *level,
+                                          /*bad*/copy *lintname));
                           }
                           _ => {
                             self.sess.span_err(
@@ -354,7 +357,7 @@ impl ctxt {
         }
 
         for triples.each |pair| {
-            let (meta, level, lintname) = *pair;
+            let (meta, level, lintname) = /*bad*/copy *pair;
             match self.dict.find(lintname) {
               None => {
                 self.span_lint(
@@ -394,7 +397,7 @@ impl ctxt {
 
 
 fn build_settings_item(i: @ast::item, &&cx: ctxt, v: visit::vt<ctxt>) {
-    do cx.with_lint_attrs(i.attrs) |cx| {
+    do cx.with_lint_attrs(/*bad*/copy i.attrs) |cx| {
         if !cx.is_default {
             cx.sess.lint_settings.settings_map.insert(i.id, cx.curr);
         }
@@ -418,7 +421,7 @@ fn build_settings_crate(sess: session::Session, crate: @ast::crate) {
         cx.set_level(lint, level);
     }
 
-    do cx.with_lint_attrs(crate.node.attrs) |cx| {
+    do cx.with_lint_attrs(/*bad*/copy crate.node.attrs) |cx| {
         // Copy out the default settings
         for cx.curr.each |k, v| {
             sess.lint_settings.default_settings.insert(k, v);
@@ -538,7 +541,7 @@ fn check_item_type_limits(cx: ty::ctxt, it: @ast::item) {
         } else {
             binop
         };
-        match ty::get(ty::expr_ty(cx, @*expr)).sty {
+        match ty::get(ty::expr_ty(cx, @/*bad*/copy *expr)).sty {
             ty::ty_int(int_ty) => {
                 let (min, max) = int_ty_range(int_ty);
                 let lit_val: i64 = match lit.node {
@@ -597,7 +600,7 @@ fn check_item_type_limits(cx: ty::ctxt, it: @ast::item) {
 }
 
 fn check_item_default_methods(cx: ty::ctxt, item: @ast::item) {
-    match item.node {
+    match /*bad*/copy item.node {
         ast::item_trait(_, _, methods) => {
             for methods.each |method| {
                 match *method {
@@ -630,10 +633,10 @@ fn check_item_deprecated_self(cx: ty::ctxt, item: @ast::item) {
               parameter or mark the method as static");
     }
 
-    match item.node {
+    match /*bad*/copy item.node {
         ast::item_trait(_, _, methods) => {
             for methods.each |method| {
-                match *method {
+                match /*bad*/copy *method {
                     ast::required(ty_method) => {
                         maybe_warn(cx, item, ty_method.self_ty);
                     }
@@ -701,10 +704,11 @@ fn check_item_ctypes(cx: ty::ctxt, it: @ast::item) {
     }
 
     match it.node {
-      ast::item_foreign_mod(nmod) if attr::foreign_abi(it.attrs) !=
-      either::Right(ast::foreign_abi_rust_intrinsic) => {
+      ast::item_foreign_mod(ref nmod)
+      if attr::foreign_abi(it.attrs) !=
+            either::Right(ast::foreign_abi_rust_intrinsic) => {
         for nmod.items.each |ni| {
-            match ni.node {
+            match /*bad*/copy ni.node {
               ast::foreign_item_fn(decl, _, _) => {
                 check_foreign_fn(cx, it.id, decl);
               }
@@ -812,14 +816,14 @@ fn check_item_non_camel_case_types(cx: ty::ctxt, it: @ast::item) {
             !ident.contains_char('_')
     }
 
-    fn ident_without_trailing_underscores(ident: ~str) -> ~str {
+    fn ident_without_trailing_underscores(+ident: ~str) -> ~str {
         match str::rfind(ident, |c| c != '_') {
             Some(idx) => (ident).slice(0, idx + 1),
             None => { ident } // all underscores
         }
     }
 
-    fn ident_without_leading_underscores(ident: ~str) -> ~str {
+    fn ident_without_leading_underscores(+ident: ~str) -> ~str {
         match str::find(ident, |c| c != '_') {
           Some(idx) => ident.slice(idx, ident.len()),
           None => {
diff --git a/src/librustc/middle/liveness.rs b/src/librustc/middle/liveness.rs
index da1f82a33b7..91e6ed289bd 100644
--- a/src/librustc/middle/liveness.rs
+++ b/src/librustc/middle/liveness.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 /*!
  * A classic liveness analysis based on dataflow over the AST.  Computes,
  * for each local variable in a function, whether that variable is live
@@ -1032,7 +1033,7 @@ impl Liveness {
     }
 
     fn propagate_through_decl(decl: @decl, succ: LiveNode) -> LiveNode {
-        match decl.node {
+        match /*bad*/copy decl.node {
           decl_local(locals) => {
             do locals.foldr(succ) |local, succ| {
                 self.propagate_through_local(*local, succ)
@@ -1081,7 +1082,7 @@ impl Liveness {
         debug!("propagate_through_expr: %s",
              expr_to_str(expr, self.tcx.sess.intr()));
 
-        match expr.node {
+        match /*bad*/copy expr.node {
           // Interesting cases with control flow or which gen/kill
 
           expr_path(_) => {
@@ -1562,7 +1563,7 @@ fn check_call(args: &[@expr],
 }
 
 fn check_expr(expr: @expr, &&self: @Liveness, vt: vt<@Liveness>) {
-    match expr.node {
+    match /*bad*/copy expr.node {
       expr_path(_) => {
         for self.variable_from_def_map(expr.id, expr.span).each |var| {
             let ln = self.live_node(expr.id, expr.span);
diff --git a/src/librustc/middle/mem_categorization.rs b/src/librustc/middle/mem_categorization.rs
index 04c57025157..1bbdc699377 100644
--- a/src/librustc/middle/mem_categorization.rs
+++ b/src/librustc/middle/mem_categorization.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 /*!
  * # Categorization
  *
@@ -913,7 +914,7 @@ impl &mem_categorization_ctxt {
                pat.id, pprust::pat_to_str(pat, tcx.sess.intr()),
                self.cmt_to_repr(cmt));
 
-        match pat.node {
+        match /*bad*/copy pat.node {
           ast::pat_wild => {
             // _
           }
@@ -1117,7 +1118,7 @@ fn field_mutbl(tcx: ty::ctxt,
                f_name: ast::ident,
                node_id: ast::node_id) -> Option<ast::mutability> {
     // Need to refactor so that records/class fields can be treated uniformly.
-    match ty::get(base_ty).sty {
+    match /*bad*/copy ty::get(base_ty).sty {
       ty::ty_rec(fields) => {
         for fields.each |f| {
             if f.ident == f_name {
diff --git a/src/librustc/middle/mode.rs b/src/librustc/middle/mode.rs
index 28fa77d625d..a736b3d2fa6 100644
--- a/src/librustc/middle/mode.rs
+++ b/src/librustc/middle/mode.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::pat_util;
 use middle::ty;
 use middle::ty::{CopyValue, MoveValue, ReadValue, ValueMode, ctxt};
@@ -89,7 +90,7 @@ fn compute_modes_for_expr(expr: @expr,
         }
     };
 
-    match expr.node {
+    match /*bad*/copy expr.node {
         expr_call(callee, args, is_block) => {
             let callee_cx = VisitContext { mode: ReadValue, ..cx };
             compute_modes_for_expr(callee, callee_cx, v);
diff --git a/src/librustc/middle/pat_util.rs b/src/librustc/middle/pat_util.rs
index 9677c517094..54d3180dbe4 100644
--- a/src/librustc/middle/pat_util.rs
+++ b/src/librustc/middle/pat_util.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::resolve;
 use middle::ty::{CopyValue, MoveValue, ReadValue};
 use middle::ty;
diff --git a/src/librustc/middle/privacy.rs b/src/librustc/middle/privacy.rs
index b9f70bd4d33..1aa3017083c 100644
--- a/src/librustc/middle/privacy.rs
+++ b/src/librustc/middle/privacy.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 // A pass that checks to make sure private fields and methods aren't used
 // outside their scopes.
 
@@ -311,7 +312,7 @@ fn check_crate(tcx: ty::ctxt, method_map: &method_map, crate: @ast::crate) {
             visit::visit_expr(expr, method_map, visitor);
         },
         visit_pat: |pattern, method_map, visitor| {
-            match pattern.node {
+            match /*bad*/copy pattern.node {
                 pat_struct(_, fields, _) => {
                     match ty::get(ty::pat_ty(tcx, pattern)).sty {
                         ty_struct(id, _) => {
diff --git a/src/librustc/middle/region.rs b/src/librustc/middle/region.rs
index 11dde31ab39..3a263347536 100644
--- a/src/librustc/middle/region.rs
+++ b/src/librustc/middle/region.rs
@@ -17,6 +17,7 @@ region parameterized.
 
 */
 
+
 use driver::session::Session;
 use metadata::csearch;
 use middle::resolve;
diff --git a/src/librustc/middle/resolve.rs b/src/librustc/middle/resolve.rs
index 5d99b9ca939..625ed9076e7 100644
--- a/src/librustc/middle/resolve.rs
+++ b/src/librustc/middle/resolve.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use driver::session::Session;
 use metadata::csearch::{each_path, get_method_names_if_trait};
 use metadata::csearch::{get_static_methods_if_impl, get_type_name_if_impl};
@@ -1126,7 +1127,7 @@ impl Resolver {
         };
         let privacy = visibility_to_privacy(item.vis, legacy);
 
-        match item.node {
+        match /*bad*/copy item.node {
             item_mod(module_) => {
                 let legacy = has_legacy_export_attr(item.attrs);
                 let (name_bindings, new_parent) =
@@ -1458,7 +1459,7 @@ impl Resolver {
           ModuleReducedGraphParent(m) => m.legacy_exports
         };
         let privacy = visibility_to_privacy(view_item.vis, legacy);
-        match view_item.node {
+        match /*bad*/copy view_item.node {
             view_item_import(view_paths) => {
                 for view_paths.each |view_path| {
                     // Extract and intern the module part of the path. For
@@ -1626,7 +1627,7 @@ impl Resolver {
             self.add_child(name, parent, ForbidDuplicateValues,
                            foreign_item.span);
 
-        match foreign_item.node {
+        match /*bad*/copy foreign_item.node {
             foreign_item_fn(_, purity, type_parameters) => {
                 let def = def_fn(local_def(foreign_item.id), purity);
                 (*name_bindings).define_value(Public, def, foreign_item.span);
@@ -1809,7 +1810,7 @@ impl Resolver {
 
             let mut current_module = root;
             for pieces.each |ident_str| {
-                let ident = self.session.ident_of(*ident_str);
+                let ident = self.session.ident_of(/*bad*/copy *ident_str);
                 // Create or reuse a graph node for the child.
                 let (child_name_bindings, new_parent) =
                     self.add_child(ident,
@@ -1869,9 +1870,6 @@ impl Resolver {
                 }
                 dl_impl(def) => {
                     // We only process static methods of impls here.
-                    debug!("(building reduced graph for external crate) \
-                            processing impl %s", final_ident_str);
-
                     match get_type_name_if_impl(self.session.cstore, def) {
                         None => {}
                         Some(final_ident) => {
@@ -1879,7 +1877,7 @@ impl Resolver {
                                 get_static_methods_if_impl(
                                     self.session.cstore, def);
                             match static_methods_opt {
-                                Some(static_methods) if
+                                Some(ref static_methods) if
                                     static_methods.len() >= 1 => {
                                     debug!("(building reduced graph for \
                                             external crate) processing \
@@ -1955,7 +1953,7 @@ impl Resolver {
                 }
                 dl_field => {
                     debug!("(building reduced graph for external crate) \
-                            ignoring field %s", final_ident_str);
+                            ignoring field");
                 }
             }
         }
@@ -3816,15 +3814,16 @@ impl Resolver {
         // Items with the !resolve_unexported attribute are X-ray contexts.
         // This is used to allow the test runner to run unexported tests.
         let orig_xray_flag = self.xray_context;
-        if contains_name(attr_metas(item.attrs), ~"!resolve_unexported") {
+        if contains_name(attr_metas(/*bad*/copy item.attrs),
+                         ~"!resolve_unexported") {
             self.xray_context = Xray;
         }
 
-        match item.node {
+        match /*bad*/copy item.node {
 
             // enum item: resolve all the variants' discrs,
             // then resolve the ty params
-            item_enum(ref enum_def, type_parameters) => {
+            item_enum(ref enum_def, ref type_parameters) => {
 
                 for (*enum_def).variants.each() |variant| {
                     do variant.node.disr_expr.iter() |dis_expr| {
@@ -3839,11 +3838,9 @@ impl Resolver {
                 // n.b. the discr expr gets visted twice.
                 // but maybe it's okay since the first time will signal an
                 // error if there is one? -- tjc
-                do self.with_type_parameter_rib
-                        (HasTypeParameters(&type_parameters, item.id, 0,
-                                           NormalRibKind))
-                        || {
-
+                do self.with_type_parameter_rib(
+                    HasTypeParameters(
+                        type_parameters, item.id, 0, NormalRibKind)) {
                     visit_item(item, (), visitor);
                 }
             }
@@ -3871,7 +3868,7 @@ impl Resolver {
                                             visitor);
             }
 
-            item_trait(type_parameters, traits, ref methods) => {
+            item_trait(ref type_parameters, ref traits, ref methods) => {
                 // Create a new rib for the self type.
                 let self_type_rib = @Rib(NormalRibKind);
                 (*self.type_ribs).push(self_type_rib);
@@ -3880,10 +3877,11 @@ impl Resolver {
 
                 // Create a new rib for the trait-wide type parameters.
                 do self.with_type_parameter_rib
-                        (HasTypeParameters(&type_parameters, item.id, 0,
+                        (HasTypeParameters(type_parameters, item.id, 0,
                                            NormalRibKind)) {
 
-                    self.resolve_type_parameters(type_parameters, visitor);
+                    self.resolve_type_parameters(/*bad*/copy *type_parameters,
+                                                 visitor);
 
                     // Resolve derived traits.
                     for traits.each |trt| {
@@ -3922,8 +3920,9 @@ impl Resolver {
 
                                 // Resolve the method-specific type
                                 // parameters.
-                                self.resolve_type_parameters((*ty_m).tps,
-                                                             visitor);
+                                self.resolve_type_parameters(
+                                    /*bad*/copy (*ty_m).tps,
+                                    visitor);
 
                                 for (*ty_m).decl.inputs.each |argument| {
                                     self.resolve_type(argument.ty, visitor);
@@ -3949,7 +3948,7 @@ impl Resolver {
             item_struct(struct_def, ty_params) => {
                 self.resolve_struct(item.id,
                                    @copy ty_params,
-                                   struct_def.fields,
+                                   /*bad*/copy struct_def.fields,
                                    struct_def.dtor,
                                    visitor);
             }
@@ -3964,7 +3963,7 @@ impl Resolver {
             item_foreign_mod(foreign_module) => {
                 do self.with_scope(Some(item.ident)) {
                     for foreign_module.items.each |foreign_item| {
-                        match foreign_item.node {
+                        match /*bad*/copy foreign_item.node {
                             foreign_item_fn(_, _, type_parameters) => {
                                 do self.with_type_parameter_rib
                                     (HasTypeParameters(&type_parameters,
@@ -3986,7 +3985,7 @@ impl Resolver {
                 }
             }
 
-            item_fn(fn_decl, _, ty_params, ref block) => {
+            item_fn(ref fn_decl, _, ref ty_params, ref block) => {
                 // If this is the main function, we must record it in the
                 // session.
                 //
@@ -4001,9 +4000,9 @@ impl Resolver {
                 }
 
                 self.resolve_function(OpaqueFunctionRibKind,
-                                      Some(@fn_decl),
+                                      Some(@/*bad*/copy *fn_decl),
                                       HasTypeParameters
-                                        (&ty_params,
+                                        (ty_params,
                                          item.id,
                                          0,
                                          OpaqueFunctionRibKind),
@@ -4128,7 +4127,8 @@ impl Resolver {
                     // Continue.
                 }
                 HasTypeParameters(type_parameters, _, _, _) => {
-                    self.resolve_type_parameters(*type_parameters, visitor);
+                    self.resolve_type_parameters(/*bad*/copy *type_parameters,
+                                                 visitor);
                 }
             }
 
@@ -4200,7 +4200,8 @@ impl Resolver {
                                          OpaqueFunctionRibKind)) {
 
             // Resolve the type parameters.
-            self.resolve_type_parameters(*type_parameters, visitor);
+            self.resolve_type_parameters(/*bad*/copy *type_parameters,
+                                         visitor);
 
             // Resolve fields.
             for fields.each |field| {
@@ -4247,7 +4248,7 @@ impl Resolver {
         };
 
         self.resolve_function(rib_kind,
-                              Some(@method.decl),
+                              Some(@/*bad*/copy method.decl),
                               type_parameters,
                               method.body,
                               self_binding,
@@ -4269,7 +4270,8 @@ impl Resolver {
                                         (borrowed_type_parameters, id, 0,
                                          NormalRibKind)) {
             // Resolve the type parameters.
-            self.resolve_type_parameters(type_parameters, visitor);
+            self.resolve_type_parameters(/*bad*/copy type_parameters,
+                                         visitor);
 
             // Resolve the trait reference, if necessary.
             let original_trait_refs = self.current_trait_refs;
@@ -5114,7 +5116,8 @@ impl Resolver {
                         self.record_def(expr.id, def);
                     }
                     None => {
-                        let wrong_name = self.idents_to_str(path.idents);
+                        let wrong_name = self.idents_to_str(
+                            /*bad*/copy path.idents);
                         if self.name_exists_in_scope_struct(wrong_name) {
                             self.session.span_err(expr.span,
                                         fmt!("unresolved name: `%s`. \
@@ -5133,10 +5136,10 @@ impl Resolver {
                 visit_expr(expr, (), visitor);
             }
 
-            expr_fn(_, fn_decl, ref block, capture_clause) |
-            expr_fn_block(fn_decl, ref block, capture_clause) => {
+            expr_fn(_, ref fn_decl, ref block, capture_clause) |
+            expr_fn_block(ref fn_decl, ref block, capture_clause) => {
                 self.resolve_function(FunctionRibKind(expr.id, block.node.id),
-                                      Some(@fn_decl),
+                                      Some(@/*bad*/copy *fn_decl),
                                       NoTypeParameters,
                                       (*block),
                                       NoSelfBinding,
diff --git a/src/librustc/middle/trans/alt.rs b/src/librustc/middle/trans/alt.rs
index 43c7f74ead2..a183bd453d0 100644
--- a/src/librustc/middle/trans/alt.rs
+++ b/src/librustc/middle/trans/alt.rs
@@ -142,6 +142,7 @@
  *
  */
 
+
 use back::abi;
 use lib::llvm::llvm;
 use lib::llvm::{ValueRef, BasicBlockRef};
@@ -499,7 +500,7 @@ fn enter_opt(bcx: block, m: &[@Match/&r], opt: &Opt, col: uint,
     let tcx = bcx.tcx();
     let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
     do enter_match(bcx, tcx.def_map, m, col, val) |p| {
-        match p.node {
+        match /*bad*/copy p.node {
             ast::pat_enum(_, subpats) => {
                 if opt_eq(tcx, &variant_opt(tcx, p.id), opt) {
                     Some(option::get_or_default(subpats,
@@ -600,7 +601,7 @@ fn enter_rec_or_struct(bcx: block, dm: DefMap, m: &[@Match/&r], col: uint,
 
     let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
     do enter_match(bcx, dm, m, col, val) |p| {
-        match p.node {
+        match /*bad*/copy p.node {
             ast::pat_rec(fpats, _) | ast::pat_struct(_, fpats, _) => {
                 let mut pats = ~[];
                 for vec::each(fields) |fname| {
@@ -632,7 +633,7 @@ fn enter_tup(bcx: block, dm: DefMap, m: &[@Match/&r],
 
     let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
     do enter_match(bcx, dm, m, col, val) |p| {
-        match p.node {
+        match /*bad*/copy p.node {
             ast::pat_tup(elts) => {
                 Some(elts)
             }
@@ -657,7 +658,7 @@ fn enter_tuple_struct(bcx: block, dm: DefMap, m: &[@Match/&r], col: uint,
 
     let dummy = @{id: 0, node: ast::pat_wild, span: dummy_sp()};
     do enter_match(bcx, dm, m, col, val) |p| {
-        match p.node {
+        match /*bad*/copy p.node {
             ast::pat_enum(_, Some(elts)) => Some(elts),
             _ => {
                 assert_is_binding_or_wild(bcx, p);
@@ -754,7 +755,7 @@ fn get_options(ccx: @crate_ctxt, m: &[@Match], col: uint) -> ~[Opt] {
     let found = DVec();
     for vec::each(m) |br| {
         let cur = br.pats[col];
-        match cur.node {
+        match /*bad*/copy cur.node {
             ast::pat_lit(l) => {
                 add_to_set(ccx.tcx, &found, lit(ExprLit(l)));
             }
@@ -812,7 +813,10 @@ fn extract_variant_args(bcx: block, pat_id: ast::node_id,
     let _icx = bcx.insn_ctxt("alt::extract_variant_args");
     let ccx = bcx.fcx.ccx;
     let enum_ty_substs = match ty::get(node_id_type(bcx, pat_id)).sty {
-      ty::ty_enum(id, ref substs) => { assert id == vdefs.enm; (*substs).tps }
+      ty::ty_enum(id, ref substs) => {
+        assert id == vdefs.enm;
+        /*bad*/copy (*substs).tps
+      }
       _ => bcx.sess().bug(~"extract_variant_args: pattern has non-enum type")
     };
     let mut blobptr = val;
@@ -828,7 +832,7 @@ fn extract_variant_args(bcx: block, pat_id: ast::node_id,
     let vdefs_var = vdefs.var;
     let args = do vec::from_fn(size) |i| {
         GEP_enum(bcx, blobptr, vdefs_tg, vdefs_var,
-                 enum_ty_substs, i)
+                 /*bad*/copy enum_ty_substs, i)
     };
     return {vals: args, bcx: bcx};
 }
@@ -873,7 +877,7 @@ fn collect_record_or_struct_fields(bcx: block, m: &[@Match], col: uint) ->
                                    ~[ast::ident] {
     let mut fields: ~[ast::ident] = ~[];
     for vec::each(m) |br| {
-        match br.pats[col].node {
+        match /*bad*/copy br.pats[col].node {
           ast::pat_rec(fs, _) => extend(&mut fields, fs),
           ast::pat_struct(_, fs, _) => {
             match ty::get(node_id_type(bcx, br.pats[col].id)).sty {
@@ -1259,7 +1263,7 @@ fn compile_submatch(bcx: block,
 
     if any_tup_pat(m, col) {
         let tup_ty = node_id_type(bcx, pat_id);
-        let n_tup_elts = match ty::get(tup_ty).sty {
+        let n_tup_elts = match /*bad*/copy ty::get(tup_ty).sty {
           ty::ty_tup(elts) => elts.len(),
           _ => ccx.sess.bug(~"non-tuple type in tuple pattern")
         };
@@ -1485,7 +1489,7 @@ fn compile_submatch(bcx: block,
             var(_, vdef) => {
                 let args = extract_variant_args(opt_cx, pat_id, vdef, val);
                 size = args.vals.len();
-                unpacked = args.vals;
+                unpacked = /*bad*/copy args.vals;
                 opt_cx = args.bcx;
             }
             vec_len_eq(n) | vec_len_ge(n) => {
@@ -1495,7 +1499,7 @@ fn compile_submatch(bcx: block,
                 };
                 let args = extract_vec_elems(opt_cx, pat_id, n, tail, val);
                 size = args.vals.len();
-                unpacked = args.vals;
+                unpacked = /*bad*/copy args.vals;
                 opt_cx = args.bcx;
             }
             lit(_) | range(_, _) => ()
@@ -1634,7 +1638,7 @@ fn trans_alt_inner(scope_cx: block,
 
     return controlflow::join_blocks(scope_cx, dvec::unwrap(move arm_cxs));
 
-    fn mk_fail(bcx: block, sp: span, msg: ~str,
+    fn mk_fail(bcx: block, sp: span, +msg: ~str,
                finished: @mut Option<BasicBlockRef>) -> BasicBlockRef {
         match *finished { Some(bb) => return bb, _ => () }
         let fail_cx = sub_block(bcx, ~"case_fallthrough");
@@ -1663,7 +1667,7 @@ fn bind_irrefutable_pat(bcx: block,
     let mut bcx = bcx;
 
     // Necessary since bind_irrefutable_pat is called outside trans_alt
-    match pat.node {
+    match /*bad*/copy pat.node {
         ast::pat_ident(_, _,inner) => {
             if pat_is_variant_or_struct(bcx.tcx().def_map, pat) {
                 return bcx;
diff --git a/src/librustc/middle/trans/base.rs b/src/librustc/middle/trans/base.rs
index d87b383247b..c20747b54b5 100644
--- a/src/librustc/middle/trans/base.rs
+++ b/src/librustc/middle/trans/base.rs
@@ -23,6 +23,7 @@
 //     but many TypeRefs correspond to one ty::t; for instance, tup(int, int,
 //     int) and rec(x=int, y=int, z=int) will have the same TypeRef.
 
+
 use back::link::{mangle_exported_name};
 use back::link::{mangle_internal_name_by_path_and_seq};
 use back::link::{mangle_internal_name_by_path};
@@ -126,7 +127,7 @@ impl fn_ctxt: get_insn_ctxt {
     }
 }
 
-fn log_fn_time(ccx: @crate_ctxt, name: ~str, start: time::Timespec,
+fn log_fn_time(ccx: @crate_ctxt, +name: ~str, start: time::Timespec,
                end: time::Timespec) {
     let elapsed = 1000 * ((end.sec - start.sec) as int) +
         ((end.nsec as int) - (start.nsec as int)) / 1000000;
@@ -142,13 +143,13 @@ fn decl_fn(llmod: ModuleRef, name: ~str, cc: lib::llvm::CallConv,
     return llfn;
 }
 
-fn decl_cdecl_fn(llmod: ModuleRef, name: ~str, llty: TypeRef) -> ValueRef {
+fn decl_cdecl_fn(llmod: ModuleRef, +name: ~str, llty: TypeRef) -> ValueRef {
     return decl_fn(llmod, name, lib::llvm::CCallConv, llty);
 }
 
 // Only use this if you are going to actually define the function. It's
 // not valid to simply declare a function as internal.
-fn decl_internal_cdecl_fn(llmod: ModuleRef, name: ~str, llty: TypeRef) ->
+fn decl_internal_cdecl_fn(llmod: ModuleRef, +name: ~str, llty: TypeRef) ->
    ValueRef {
     let llfn = decl_cdecl_fn(llmod, name, llty);
     lib::llvm::SetLinkage(llfn, lib::llvm::InternalLinkage);
@@ -156,17 +157,22 @@ fn decl_internal_cdecl_fn(llmod: ModuleRef, name: ~str, llty: TypeRef) ->
 }
 
 fn get_extern_fn(externs: HashMap<~str, ValueRef>,
-                 llmod: ModuleRef, name: ~str,
-                 cc: lib::llvm::CallConv, ty: TypeRef) -> ValueRef {
-    if externs.contains_key(name) { return externs.get(name); }
-    let f = decl_fn(llmod, name, cc, ty);
+                 llmod: ModuleRef,
+                 +name: ~str,
+                 cc: lib::llvm::CallConv,
+                 ty: TypeRef) -> ValueRef {
+    // XXX: Bad copy.
+    if externs.contains_key(copy name) { return externs.get(name); }
+    // XXX: Bad copy.
+    let f = decl_fn(llmod, copy name, cc, ty);
     externs.insert(name, f);
     return f;
 }
 
 fn get_extern_const(externs: HashMap<~str, ValueRef>, llmod: ModuleRef,
-                    name: ~str, ty: TypeRef) -> ValueRef {
-    if externs.contains_key(name) { return externs.get(name); }
+                    +name: ~str, ty: TypeRef) -> ValueRef {
+    // XXX: Bad copy.
+    if externs.contains_key(copy name) { return externs.get(name); }
     let c = str::as_c_str(name, |buf| llvm::LLVMAddGlobal(llmod, ty, buf));
     externs.insert(name, c);
     return c;
@@ -175,7 +181,8 @@ fn get_extern_const(externs: HashMap<~str, ValueRef>, llmod: ModuleRef,
 fn get_simple_extern_fn(cx: block,
                         externs: HashMap<~str, ValueRef>,
                         llmod: ModuleRef,
-                        name: ~str, n_args: int) -> ValueRef {
+                        +name: ~str,
+                        n_args: int) -> ValueRef {
     let _icx = cx.insn_ctxt("get_simple_extern_fn");
     let ccx = cx.fcx.ccx;
     let inputs = vec::from_elem(n_args as uint, ccx.int_type);
@@ -185,7 +192,7 @@ fn get_simple_extern_fn(cx: block,
 }
 
 fn trans_foreign_call(cx: block, externs: HashMap<~str, ValueRef>,
-                      llmod: ModuleRef, name: ~str, args: ~[ValueRef]) ->
+                      llmod: ModuleRef, +name: ~str, args: ~[ValueRef]) ->
    ValueRef {
     let _icx = cx.insn_ctxt("trans_foreign_call");
     let n = args.len() as int;
@@ -413,8 +420,9 @@ fn set_glue_inlining(f: ValueRef, t: ty::t) {
 
 // Double-check that we never ask LLVM to declare the same symbol twice. It
 // silently mangles such symbols, breaking our linkage model.
-fn note_unique_llvm_symbol(ccx: @crate_ctxt, sym: ~str) {
-    if ccx.all_llvm_symbols.contains_key(sym) {
+fn note_unique_llvm_symbol(ccx: @crate_ctxt, +sym: ~str) {
+    // XXX: Bad copy.
+    if ccx.all_llvm_symbols.contains_key(copy sym) {
         ccx.sess.bug(~"duplicate LLVM symbol: " + sym);
     }
     ccx.all_llvm_symbols.insert(sym, ());
@@ -570,7 +578,8 @@ fn iter_structural_ty(cx: block, av: ValueRef, t: ty::t,
             let mut j = 0u;
             let v_id = variant.id;
             for vec::each(fn_ty.sig.inputs) |a| {
-                let llfldp_a = GEP_enum(cx, a_tup, tid, v_id, tps, j);
+                let llfldp_a = GEP_enum(cx, a_tup, tid, v_id,
+                                        /*bad*/copy tps, j);
                 // XXX: Is "None" right here?
                 let ty_subst = ty::subst_tps(ccx.tcx, tps, None, a.ty);
                 cx = f(cx, llfldp_a, ty_subst);
@@ -585,11 +594,8 @@ fn iter_structural_ty(cx: block, av: ValueRef, t: ty::t,
         return cx;
     }
 
-    /*
-    Typestate constraint that shows the unimpl case doesn't happen?
-    */
     let mut cx = cx;
-    match ty::get(t).sty {
+    match /*bad*/copy ty::get(t).sty {
       ty::ty_rec(*) | ty::ty_struct(*) => {
           do expr::with_field_tys(cx.tcx(), t, None) |_has_dtor, field_tys| {
               for vec::eachi(field_tys) |i, field_ty| {
@@ -615,8 +621,12 @@ fn iter_structural_ty(cx: block, av: ValueRef, t: ty::t,
 
         // Cast the enums to types we can GEP into.
         if n_variants == 1u {
-            return iter_variant(cx, av, variants[0],
-                             (*substs).tps, tid, f);
+            return iter_variant(cx,
+                                av,
+                                variants[0],
+                                /*bad*/copy substs.tps,
+                                tid,
+                                f);
         }
 
         let ccx = cx.ccx();
@@ -641,7 +651,7 @@ fn iter_structural_ty(cx: block, av: ValueRef, t: ty::t,
             AddCase(llswitch, C_int(ccx, variant.disr_val), variant_cx.llbb);
             let variant_cx =
                 iter_variant(variant_cx, llunion_a_ptr, *variant,
-                             (*substs).tps, tid, f);
+                             /*bad*/copy (*substs).tps, tid, f);
             Br(variant_cx, next_cx.llbb);
         }
         return next_cx;
@@ -711,7 +721,7 @@ fn fail_if_zero(cx: block, span: span, divmod: ast::binop,
       }
     };
     do with_cond(cx, is_zero) |bcx| {
-        controlflow::trans_fail(bcx, Some(span), text)
+        controlflow::trans_fail(bcx, Some(span), /*bad*/copy text)
     }
 }
 
@@ -754,7 +764,7 @@ fn lookup_discriminant(ccx: @crate_ctxt, vid: ast::def_id) -> ValueRef {
     }
 }
 
-fn invoke(bcx: block, llfn: ValueRef, llargs: ~[ValueRef]) -> block {
+fn invoke(bcx: block, llfn: ValueRef, +llargs: ~[ValueRef]) -> block {
     let _icx = bcx.insn_ctxt("invoke_");
     if bcx.unreachable { return bcx; }
     if need_invoke(bcx) {
@@ -954,16 +964,17 @@ fn load_if_immediate(cx: block, v: ValueRef, t: ty::t) -> ValueRef {
     return v;
 }
 
-fn trans_trace(bcx: block, sp_opt: Option<span>, trace_str: ~str) {
+fn trans_trace(bcx: block, sp_opt: Option<span>, +trace_str: ~str) {
     if !bcx.sess().trace() { return; }
     let _icx = bcx.insn_ctxt("trans_trace");
-    add_comment(bcx, trace_str);
+    // XXX: Bad copy.
+    add_comment(bcx, copy trace_str);
     let V_trace_str = C_cstr(bcx.ccx(), trace_str);
     let {V_filename, V_line} = match sp_opt {
       Some(sp) => {
         let sess = bcx.sess();
         let loc = sess.parse_sess.cm.lookup_char_pos(sp.lo);
-        {V_filename: C_cstr(bcx.ccx(), loc.file.name),
+        {V_filename: C_cstr(bcx.ccx(), /*bad*/copy loc.file.name),
          V_line: loc.line as int}
       }
       None => {
@@ -1057,7 +1068,7 @@ fn trans_stmt(cx: block, s: ast::stmt) -> block {
             bcx = expr::trans_into(cx, e, expr::Ignore);
         }
         ast::stmt_decl(d, _) => {
-            match d.node {
+            match /*bad*/copy d.node {
                 ast::decl_local(locals) => {
                     for vec::each(locals) |local| {
                         bcx = init_local(bcx, *local);
@@ -1078,7 +1089,7 @@ fn trans_stmt(cx: block, s: ast::stmt) -> block {
 // You probably don't want to use this one. See the
 // next three functions instead.
 fn new_block(cx: fn_ctxt, parent: Option<block>, +kind: block_kind,
-             is_lpad: bool, name: ~str, opt_node_info: Option<node_info>)
+             is_lpad: bool, +name: ~str, opt_node_info: Option<node_info>)
     -> block {
 
     let s = if cx.ccx.sess.opts.save_temps || cx.ccx.sess.opts.debuginfo {
@@ -1112,13 +1123,13 @@ fn top_scope_block(fcx: fn_ctxt, opt_node_info: Option<node_info>) -> block {
 
 fn scope_block(bcx: block,
                opt_node_info: Option<node_info>,
-               n: ~str) -> block {
+               +n: ~str) -> block {
     return new_block(bcx.fcx, Some(bcx), simple_block_scope(), bcx.is_lpad,
                   n, opt_node_info);
 }
 
 fn loop_scope_block(bcx: block, loop_break: block, loop_label: Option<ident>,
-                    n: ~str, opt_node_info: Option<node_info>) -> block {
+                    +n: ~str, opt_node_info: Option<node_info>) -> block {
     return new_block(bcx.fcx, Some(bcx), block_scope(scope_info {
         loop_break: Some(loop_break),
         loop_label: loop_label,
@@ -1129,12 +1140,12 @@ fn loop_scope_block(bcx: block, loop_break: block, loop_label: Option<ident>,
 }
 
 // Use this when creating a block for the inside of a landing pad.
-fn lpad_block(bcx: block, n: ~str) -> block {
+fn lpad_block(bcx: block, +n: ~str) -> block {
     new_block(bcx.fcx, Some(bcx), block_non_scope, true, n, None)
 }
 
 // Use this when you're making a general CFG BB within a scope.
-fn sub_block(bcx: block, n: ~str) -> block {
+fn sub_block(bcx: block, +n: ~str) -> block {
     new_block(bcx.fcx, Some(bcx), block_non_scope, bcx.is_lpad, n, None)
 }
 
@@ -1240,7 +1251,7 @@ fn leave_block(bcx: block, out_of: block) -> block {
 }
 
 fn with_scope(bcx: block, opt_node_info: Option<node_info>,
-              name: ~str, f: fn(block) -> block) -> block {
+              +name: ~str, f: fn(block) -> block) -> block {
     let _icx = bcx.insn_ctxt("with_scope");
 
     debug!("with_scope(bcx=%s, opt_node_info=%?, name=%s)",
@@ -1252,10 +1263,11 @@ fn with_scope(bcx: block, opt_node_info: Option<node_info>,
     leave_block(f(scope_cx), scope_cx)
 }
 
-fn with_scope_result(bcx: block, opt_node_info: Option<node_info>,
-                     name: ~str, f: fn(block) -> Result)
-    -> Result
-{
+fn with_scope_result(bcx: block,
+                     opt_node_info: Option<node_info>,
+                     +name: ~str,
+                     f: fn(block) -> Result)
+                  -> Result {
     let _icx = bcx.insn_ctxt("with_scope_result");
     let scope_cx = scope_block(bcx, opt_node_info, name);
     Br(bcx, scope_cx.llbb);
@@ -1264,7 +1276,7 @@ fn with_scope_result(bcx: block, opt_node_info: Option<node_info>,
 }
 
 fn with_scope_datumblock(bcx: block, opt_node_info: Option<node_info>,
-                         name: ~str, f: fn(block) -> datum::DatumBlock)
+                         +name: ~str, f: fn(block) -> datum::DatumBlock)
     -> datum::DatumBlock
 {
     use middle::trans::datum::DatumBlock;
@@ -1280,7 +1292,7 @@ fn block_locals(b: ast::blk, it: fn(@ast::local)) {
     for vec::each(b.node.stmts) |s| {
         match s.node {
           ast::stmt_decl(d, _) => {
-            match d.node {
+            match /*bad*/copy d.node {
               ast::decl_local(locals) => {
                 for vec::each(locals) |local| {
                     it(*local);
@@ -1443,11 +1455,11 @@ fn mk_standard_basic_blocks(llfn: ValueRef) ->
 //  - new_fn_ctxt
 //  - trans_args
 fn new_fn_ctxt_w_id(ccx: @crate_ctxt,
-                    path: path,
+                    +path: path,
                     llfndecl: ValueRef,
                     id: ast::node_id,
                     impl_id: Option<ast::def_id>,
-                    param_substs: Option<param_substs>,
+                    +param_substs: Option<param_substs>,
                     sp: Option<span>) -> fn_ctxt {
     let llbbs = mk_standard_basic_blocks(llfndecl);
     return @fn_ctxt_ {
@@ -1472,8 +1484,11 @@ fn new_fn_ctxt_w_id(ccx: @crate_ctxt,
     };
 }
 
-fn new_fn_ctxt(ccx: @crate_ctxt, path: path, llfndecl: ValueRef,
-               sp: Option<span>) -> fn_ctxt {
+fn new_fn_ctxt(ccx: @crate_ctxt,
+               +path: path,
+               llfndecl: ValueRef,
+               sp: Option<span>)
+            -> fn_ctxt {
     return new_fn_ctxt_w_id(ccx, path, llfndecl, -1, None, None, sp);
 }
 
@@ -1625,10 +1640,13 @@ enum self_arg { impl_self(ty::t), impl_owned_self(ty::t), no_self, }
 // trans_closure: Builds an LLVM function out of a source function.
 // If the function closes over its environment a closure will be
 // returned.
-fn trans_closure(ccx: @crate_ctxt, path: path, decl: ast::fn_decl,
-                 body: ast::blk, llfndecl: ValueRef,
+fn trans_closure(ccx: @crate_ctxt,
+                 +path: path,
+                 decl: ast::fn_decl,
+                 body: ast::blk,
+                 llfndecl: ValueRef,
                  ty_self: self_arg,
-                 param_substs: Option<param_substs>,
+                 +param_substs: Option<param_substs>,
                  id: ast::node_id,
                  impl_id: Option<ast::def_id>,
                  maybe_load_env: fn(fn_ctxt),
@@ -1640,7 +1658,8 @@ fn trans_closure(ccx: @crate_ctxt, path: path, decl: ast::fn_decl,
     // Set up arguments to the function.
     let fcx = new_fn_ctxt_w_id(ccx, path, llfndecl, id, impl_id, param_substs,
                                   Some(body.span));
-    let raw_llargs = create_llargs_for_fn_args(fcx, ty_self, decl.inputs);
+    let raw_llargs = create_llargs_for_fn_args(fcx, ty_self,
+                                               /*bad*/copy decl.inputs);
 
     // Set GC for function.
     if ccx.sess.opts.gc {
@@ -1684,12 +1703,12 @@ fn trans_closure(ccx: @crate_ctxt, path: path, decl: ast::fn_decl,
 // trans_fn: creates an LLVM function corresponding to a source language
 // function.
 fn trans_fn(ccx: @crate_ctxt,
-            path: path,
+            +path: path,
             decl: ast::fn_decl,
             body: ast::blk,
             llfndecl: ValueRef,
             ty_self: self_arg,
-            param_substs: Option<param_substs>,
+            +param_substs: Option<param_substs>,
             id: ast::node_id,
             impl_id: Option<ast::def_id>) {
     let do_time = ccx.sess.trans_stats();
@@ -1698,7 +1717,8 @@ fn trans_fn(ccx: @crate_ctxt,
     debug!("trans_fn(ty_self=%?)", ty_self);
     let _icx = ccx.insn_ctxt("trans_fn");
     ccx.stats.n_fns += 1;
-    trans_closure(ccx, path, decl, body, llfndecl, ty_self,
+    // XXX: Bad copy of `path`.
+    trans_closure(ccx, copy path, decl, body, llfndecl, ty_self,
                   param_substs, id, impl_id,
                   |fcx| {
                       if ccx.sess.opts.extra_debuginfo {
@@ -1718,7 +1738,7 @@ fn trans_enum_variant(ccx: @crate_ctxt,
                       args: ~[ast::variant_arg],
                       disr: int,
                       is_degen: bool,
-                      param_substs: Option<param_substs>,
+                      +param_substs: Option<param_substs>,
                       llfndecl: ValueRef) {
     let _icx = ccx.insn_ctxt("trans_enum_variant");
     // Translate variant arguments to function arguments.
@@ -1729,11 +1749,13 @@ fn trans_enum_variant(ccx: @crate_ctxt,
                                      ast_util::dummy_sp(),
                                      special_idents::arg),
          id: varg.id});
+    // XXX: Bad copy of `param_substs`.
     let fcx = new_fn_ctxt_w_id(ccx, ~[], llfndecl, variant.node.id, None,
-                               param_substs, None);
-    let raw_llargs = create_llargs_for_fn_args(fcx, no_self, fn_args);
+                               copy param_substs, None);
+    // XXX: Bad copy.
+    let raw_llargs = create_llargs_for_fn_args(fcx, no_self, copy fn_args);
     let ty_param_substs = match param_substs {
-      Some(substs) => substs.tys,
+      Some(ref substs) => /*bad*/copy substs.tys,
       None => ~[]
     };
     let bcx = top_scope_block(fcx, None), lltop = bcx.llbb;
@@ -1754,7 +1776,7 @@ fn trans_enum_variant(ccx: @crate_ctxt,
     let v_id = local_def(variant.node.id);
     for vec::eachi(args) |i, va| {
         let lldestptr = GEP_enum(bcx, llblobptr, t_id, v_id,
-                                 ty_param_substs, i);
+                                 /*bad*/copy ty_param_substs, i);
         // If this argument to this function is a enum, it'll have come in to
         // this function as an opaque blob due to the way that type_of()
         // works. So we have to cast to the destination's view of the type.
@@ -1774,7 +1796,7 @@ fn trans_enum_variant(ccx: @crate_ctxt,
 fn trans_tuple_struct(ccx: @crate_ctxt,
                       fields: ~[@ast::struct_field],
                       ctor_id: ast::node_id,
-                      param_substs: Option<param_substs>,
+                      +param_substs: Option<param_substs>,
                       llfndecl: ValueRef) {
     let _icx = ccx.insn_ctxt("trans_tuple_struct");
 
@@ -1792,7 +1814,9 @@ fn trans_tuple_struct(ccx: @crate_ctxt,
 
     let fcx = new_fn_ctxt_w_id(ccx, ~[], llfndecl, ctor_id, None,
                                param_substs, None);
-    let raw_llargs = create_llargs_for_fn_args(fcx, no_self, fn_args);
+
+    // XXX: Bad copy.
+    let raw_llargs = create_llargs_for_fn_args(fcx, no_self, copy fn_args);
 
     let bcx = top_scope_block(fcx, None);
     let lltop = bcx.llbb;
@@ -1816,11 +1840,14 @@ fn trans_tuple_struct(ccx: @crate_ctxt,
     finish_fn(fcx, lltop);
 }
 
-fn trans_struct_dtor(ccx: @crate_ctxt, path: path,
-    body: ast::blk, dtor_id: ast::node_id,
-    psubsts: Option<param_substs>,
-    hash_id: Option<mono_id>, parent_id: ast::def_id)
-    -> ValueRef {
+fn trans_struct_dtor(ccx: @crate_ctxt,
+                     +path: path,
+                     body: ast::blk,
+                     dtor_id: ast::node_id,
+                     +psubsts: Option<param_substs>,
+                     hash_id: Option<mono_id>,
+                     parent_id: ast::def_id)
+                  -> ValueRef {
   let tcx = ccx.tcx;
   /* Look up the parent class's def_id */
   let mut class_ty = ty::lookup_item_type(tcx, parent_id).ty;
@@ -1833,7 +1860,8 @@ fn trans_struct_dtor(ccx: @crate_ctxt, path: path,
      and returns () */
   let lldty = type_of_dtor(ccx, class_ty);
 
-  let s = get_dtor_symbol(ccx, path, dtor_id, psubsts);
+  // XXX: Bad copies.
+  let s = get_dtor_symbol(ccx, copy path, dtor_id, copy psubsts);
 
   /* Register the dtor as a function. It has external linkage */
   let lldecl = decl_internal_cdecl_fn(ccx.llmod, s, lldty);
@@ -1859,23 +1887,23 @@ fn trans_enum_def(ccx: @crate_ctxt, enum_definition: ast::enum_def,
         *i += 1;
 
         match variant.node.kind {
-            ast::tuple_variant_kind(args) if args.len() > 0 => {
+            ast::tuple_variant_kind(ref args) if args.len() > 0 => {
                 let llfn = get_item_val(ccx, variant.node.id);
-                trans_enum_variant(ccx, id, *variant, args, disr_val,
-                                   degen, None, llfn);
+                trans_enum_variant(ccx, id, *variant, /*bad*/copy *args,
+                                   disr_val, degen, None, llfn);
             }
             ast::tuple_variant_kind(_) => {
                 // Nothing to do.
             }
             ast::struct_variant_kind(struct_def) => {
-                trans_struct_def(ccx, struct_def, tps, path,
+                trans_struct_def(ccx, struct_def, /*bad*/copy tps, path,
                                  variant.node.id);
             }
             ast::enum_variant_kind(ref enum_definition) => {
                 trans_enum_def(ccx,
                                *enum_definition,
                                id,
-                               tps,
+                               /*bad*/copy tps,
                                degen,
                                path,
                                vi,
@@ -1892,19 +1920,20 @@ fn trans_item(ccx: @crate_ctxt, item: ast::item) {
         // tjc: ?
         _ => fail ~"trans_item",
     };
-    match item.node {
-      ast::item_fn(decl, purity, tps, ref body) => {
+    match /*bad*/copy item.node {
+      // XXX: Bad copies.
+      ast::item_fn(copy decl, purity, copy tps, ref body) => {
         if purity == ast::extern_fn  {
             let llfndecl = get_item_val(ccx, item.id);
             foreign::trans_foreign_fn(ccx,
                                      vec::append(
-                                         *path,
+                                         /*bad*/copy *path,
                                          ~[path_name(item.ident)]),
                                      decl, (*body), llfndecl, item.id);
         } else if tps.is_empty() {
             let llfndecl = get_item_val(ccx, item.id);
             trans_fn(ccx,
-                     vec::append(*path, ~[path_name(item.ident)]),
+                     vec::append(/*bad*/copy *path, ~[path_name(item.ident)]),
                      decl, (*body), llfndecl, no_self, None, item.id, None);
         } else {
             for vec::each((*body).node.stmts) |stmt| {
@@ -1918,26 +1947,27 @@ fn trans_item(ccx: @crate_ctxt, item: ast::item) {
         }
       }
       ast::item_impl(tps, _, _, ms) => {
-        meth::trans_impl(ccx, *path, item.ident, ms, tps, None,
+        meth::trans_impl(ccx, /*bad*/copy *path, item.ident, ms, tps, None,
                          item.id);
       }
       ast::item_mod(m) => {
         trans_mod(ccx, m);
       }
-      ast::item_enum(ref enum_definition, tps) => {
+      ast::item_enum(ref enum_definition, ref tps) => {
         if tps.len() == 0u {
             let degen = (*enum_definition).variants.len() == 1u;
             let vi = ty::enum_variants(ccx.tcx, local_def(item.id));
             let mut i = 0;
-            trans_enum_def(ccx, (*enum_definition), item.id, tps, degen, path,
-                           vi, &mut i);
+            trans_enum_def(ccx, (*enum_definition), item.id, /*bad*/copy *tps,
+                           degen, path, vi, &mut i);
         }
       }
       ast::item_const(_, expr) => consts::trans_const(ccx, expr, item.id),
       ast::item_foreign_mod(foreign_mod) => {
         let abi = match attr::foreign_abi(item.attrs) {
           either::Right(abi_) => abi_,
-          either::Left(ref msg) => ccx.sess.span_fatal(item.span, (*msg))
+          either::Left(ref msg) => ccx.sess.span_fatal(item.span,
+                                                       /*bad*/copy *msg)
         };
         foreign::trans_foreign_mod(ccx, foreign_mod, abi);
       }
@@ -1956,7 +1986,7 @@ fn trans_struct_def(ccx: @crate_ctxt, struct_def: @ast::struct_def,
     if tps.len() == 0u {
         // Translate the destructor.
         do option::iter(&struct_def.dtor) |dtor| {
-            trans_struct_dtor(ccx, *path, dtor.node.body,
+            trans_struct_dtor(ccx, /*bad*/copy *path, dtor.node.body,
                              dtor.node.id, None, None, local_def(id));
         };
 
@@ -1966,8 +1996,8 @@ fn trans_struct_def(ccx: @crate_ctxt, struct_def: @ast::struct_def,
             // otherwise this is a unit-like struct.
             Some(ctor_id) if struct_def.fields.len() > 0 => {
                 let llfndecl = get_item_val(ccx, ctor_id);
-                trans_tuple_struct(ccx, struct_def.fields, ctor_id, None,
-                                   llfndecl);
+                trans_tuple_struct(ccx, /*bad*/copy struct_def.fields,
+                                   ctor_id, None, llfndecl);
             }
             Some(_) | None => {}
         }
@@ -1991,30 +2021,35 @@ fn get_pair_fn_ty(llpairty: TypeRef) -> TypeRef {
     return struct_elt(llpairty, 0u);
 }
 
-fn register_fn(ccx: @crate_ctxt, sp: span, path: path,
-               node_id: ast::node_id) -> ValueRef {
+fn register_fn(ccx: @crate_ctxt,
+               sp: span,
+               +path: path,
+               node_id: ast::node_id)
+            -> ValueRef {
     let t = ty::node_id_to_type(ccx.tcx, node_id);
     register_fn_full(ccx, sp, path, node_id, t)
 }
 
-fn register_fn_full(ccx: @crate_ctxt, sp: span, path: path,
+fn register_fn_full(ccx: @crate_ctxt, sp: span, +path: path,
                     node_id: ast::node_id, node_type: ty::t) -> ValueRef {
     let llfty = type_of_fn_from_ty(ccx, node_type);
     register_fn_fuller(ccx, sp, path, node_id, node_type,
                        lib::llvm::CCallConv, llfty)
 }
 
-fn register_fn_fuller(ccx: @crate_ctxt, sp: span, path: path,
+fn register_fn_fuller(ccx: @crate_ctxt, sp: span, +path: path,
                       node_id: ast::node_id, node_type: ty::t,
                       cc: lib::llvm::CallConv, llfty: TypeRef) -> ValueRef {
-    let ps: ~str = mangle_exported_name(ccx, path, node_type);
-    let llfn: ValueRef = decl_fn(ccx.llmod, ps, cc, llfty);
-    ccx.item_symbols.insert(node_id, ps);
-
-    debug!("register_fn_fuller created fn %s for item %d with path %s",
-           val_str(ccx.tn, llfn), node_id,
+    debug!("register_fn_fuller creating fn for item %d with path %s",
+           node_id,
            ast_map::path_to_str(path, ccx.sess.parse_sess.interner));
 
+    // XXX: Bad copy.
+    let ps: ~str = mangle_exported_name(ccx, copy path, node_type);
+    // XXX: Bad copy.
+    let llfn: ValueRef = decl_fn(ccx.llmod, copy ps, cc, llfty);
+    ccx.item_symbols.insert(node_id, ps);
+
     let is_main = is_main_name(path) && !ccx.sess.building_library;
     if is_main { create_main_wrapper(ccx, sp, llfn); }
     llfn
@@ -2098,7 +2133,7 @@ fn fill_fn_pair(bcx: block, pair: ValueRef, llfn: ValueRef,
 
 fn item_path(ccx: @crate_ctxt, i: @ast::item) -> path {
     vec::append(
-        *match ccx.tcx.items.get(i.id) {
+        /*bad*/copy *match ccx.tcx.items.get(i.id) {
             ast_map::node_item(_, p) => p,
                 // separate map for paths?
             _ => fail ~"item_path"
@@ -2108,17 +2143,21 @@ fn item_path(ccx: @crate_ctxt, i: @ast::item) -> path {
 
 /* If there's already a symbol for the dtor with <id> and substs <substs>,
    return it; otherwise, create one and register it, returning it as well */
-fn get_dtor_symbol(ccx: @crate_ctxt, path: path, id: ast::node_id,
-                   substs: Option<param_substs>) -> ~str {
+fn get_dtor_symbol(ccx: @crate_ctxt,
+                   +path: path,
+                   id: ast::node_id,
+                   +substs: Option<param_substs>)
+                -> ~str {
   let t = ty::node_id_to_type(ccx.tcx, id);
   match ccx.item_symbols.find(id) {
-     Some(ref s) => (*s),
+     Some(ref s) => (/*bad*/copy *s),
      None if substs.is_none() => {
        let s = mangle_exported_name(
            ccx,
            vec::append(path, ~[path_name((ccx.names)(~"dtor"))]),
            t);
-       ccx.item_symbols.insert(id, s);
+       // XXX: Bad copy, use `@str`?
+       ccx.item_symbols.insert(id, copy s);
        s
      }
      None   => {
@@ -2152,7 +2191,8 @@ fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
         let mut exprt = false;
         let val = match ccx.tcx.items.get(id) {
           ast_map::node_item(i, pth) => {
-            let my_path = vec::append(*pth, ~[path_name(i.ident)]);
+            let my_path = vec::append(/*bad*/copy *pth,
+                                      ~[path_name(i.ident)]);
             match i.node {
               ast::item_const(_, _) => {
                 let typ = ty::node_id_to_type(ccx.tcx, i.id);
@@ -2169,7 +2209,7 @@ fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
                 } else {
                     foreign::register_foreign_fn(ccx, i.span, my_path, i.id)
                 };
-                set_inline_hint_if_appr(i.attrs, llfn);
+                set_inline_hint_if_appr(/*bad*/copy i.attrs, llfn);
                 llfn
               }
               _ => fail ~"get_item_val: weird result in table"
@@ -2197,7 +2237,8 @@ fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
             match ni.node {
                 ast::foreign_item_fn(*) => {
                     register_fn(ccx, ni.span,
-                                vec::append(*pth, ~[path_name(ni.ident)]),
+                                vec::append(/*bad*/copy *pth,
+                                            ~[path_name(ni.ident)]),
                                 ni.id)
                 }
                 ast::foreign_item_const(*) => {
@@ -2223,7 +2264,7 @@ fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
             let lldty = T_fn(~[T_ptr(type_of(ccx, ty::mk_nil(tcx))),
                     T_ptr(type_of(ccx, class_ty))],
                                    llvm::LLVMVoidType());
-            let s = get_dtor_symbol(ccx, *pt, dt.node.id, None);
+            let s = get_dtor_symbol(ccx, /*bad*/copy *pt, dt.node.id, None);
 
             /* Make the declaration for the dtor */
             let llfn = decl_internal_cdecl_fn(ccx.llmod, s, lldty);
@@ -2233,10 +2274,10 @@ fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
 
           ast_map::node_variant(ref v, enm, pth) => {
             let llfn;
-            match (*v).node.kind {
+            match /*bad*/copy (*v).node.kind {
                 ast::tuple_variant_kind(args) => {
                     assert args.len() != 0u;
-                    let pth = vec::append(*pth,
+                    let pth = vec::append(/*bad*/copy *pth,
                                           ~[path_name(enm.ident),
                                             path_name((*v).node.name)]);
                     llfn = match enm.node {
@@ -2266,7 +2307,7 @@ fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
                 }
                 Some(ctor_id) => {
                     let llfn = register_fn(ccx, struct_item.span,
-                                           *struct_path, ctor_id);
+                                           /*bad*/copy *struct_path, ctor_id);
                     set_inline_hint(llfn);
                     llfn
                 }
@@ -2289,10 +2330,10 @@ fn get_item_val(ccx: @crate_ctxt, id: ast::node_id) -> ValueRef {
 fn register_method(ccx: @crate_ctxt, id: ast::node_id, pth: @ast_map::path,
                 m: @ast::method) -> ValueRef {
     let mty = ty::node_id_to_type(ccx.tcx, id);
-    let pth = vec::append(*pth, ~[path_name((ccx.names)(~"meth")),
+    let pth = vec::append(/*bad*/copy *pth, ~[path_name((ccx.names)(~"meth")),
                                   path_name(m.ident)]);
     let llfn = register_fn_full(ccx, m.span, pth, id, mty);
-    set_inline_hint_if_appr(m.attrs, llfn);
+    set_inline_hint_if_appr(/*bad*/copy m.attrs, llfn);
     llfn
 }
 
@@ -2306,11 +2347,14 @@ fn trans_constant(ccx: @crate_ctxt, it: @ast::item) {
         let mut i = 0;
         let path = item_path(ccx, it);
         for vec::each((*enum_definition).variants) |variant| {
-            let p = vec::append(path, ~[path_name(variant.node.name),
-                                        path_name(special_idents::descrim)]);
+            let p = vec::append(/*bad*/copy path, ~[
+                path_name(variant.node.name),
+                path_name(special_idents::descrim)
+            ]);
             let s = mangle_exported_name(ccx, p, ty::mk_int(ccx.tcx));
             let disr_val = vi[i].disr_val;
-            note_unique_llvm_symbol(ccx, s);
+            // XXX: Bad copy.
+            note_unique_llvm_symbol(ccx, copy s);
             let discrim_gvar = str::as_c_str(s, |buf| {
                 llvm::LLVMAddGlobal(ccx.llmod, ccx.int_type, buf)
             });
@@ -2639,11 +2683,10 @@ fn fill_crate_map(ccx: @crate_ctxt, map: ValueRef) {
           C_array(ccx.int_type, subcrates)]));
 }
 
-fn crate_ctxt_to_encode_parms(cx: @crate_ctxt)
-    -> encoder::encode_parms {
-
+fn crate_ctxt_to_encode_parms(cx: @crate_ctxt) -> encoder::encode_parms {
+    // XXX: Bad copy of `c`, whatever it is.
     let encode_inlined_item =
-        |a,b,c,d| astencode::encode_inlined_item(a, b, c, d, cx.maps);
+        |a,b,c,d| astencode::encode_inlined_item(a, b, copy c, d, cx.maps);
 
     return {
         diag: cx.sess.diagnostic(),
@@ -2652,7 +2695,7 @@ fn crate_ctxt_to_encode_parms(cx: @crate_ctxt)
         reexports2: cx.exp_map2,
         item_symbols: cx.item_symbols,
         discrim_symbols: cx.discrim_symbols,
-        link_meta: cx.link_meta,
+        link_meta: /*bad*/copy cx.link_meta,
         cstore: cx.sess.cstore,
         encode_inlined_item: encode_inlined_item
     };
@@ -2715,8 +2758,8 @@ fn trans_crate(sess: session::Session,
         llvm::LLVMModuleCreateWithNameInContext
             (buf, llvm::LLVMGetGlobalContext())
     });
-    let data_layout = sess.targ_cfg.target_strs.data_layout;
-    let targ_triple = sess.targ_cfg.target_strs.target_triple;
+    let data_layout = /*bad*/copy sess.targ_cfg.target_strs.data_layout;
+    let targ_triple = /*bad*/copy sess.targ_cfg.target_strs.target_triple;
     let _: () =
         str::as_c_str(data_layout,
                     |buf| llvm::LLVMSetDataLayout(llmod, buf));
@@ -2724,7 +2767,8 @@ fn trans_crate(sess: session::Session,
         str::as_c_str(targ_triple,
                     |buf| llvm::LLVMSetTarget(llmod, buf));
     let targ_cfg = sess.targ_cfg;
-    let td = mk_target_data(sess.targ_cfg.target_strs.data_layout);
+    let td = mk_target_data(
+        /*bad*/copy sess.targ_cfg.target_strs.data_layout);
     let tn = mk_type_names();
     let intrinsics = declare_intrinsics(llmod);
     if sess.opts.extra_debuginfo {
@@ -2739,9 +2783,9 @@ fn trans_crate(sess: session::Session,
     lib::llvm::associate_type(tn, ~"tydesc", tydesc_type);
     let crate_map = decl_crate_map(sess, link_meta, llmod);
     let dbg_cx = if sess.opts.debuginfo {
-        option::Some(debuginfo::mk_ctxt(llmod_id, sess.parse_sess.interner))
+        Some(debuginfo::mk_ctxt(copy llmod_id, sess.parse_sess.interner))
     } else {
-        option::None
+        None
     };
 
     let ccx = @crate_ctxt {
@@ -2756,7 +2800,7 @@ fn trans_crate(sess: session::Session,
           reachable: reachable,
           item_symbols: HashMap(),
           mut main_fn: None::<ValueRef>,
-          link_meta: link_meta,
+          link_meta: copy link_meta,    // XXX: Bad copy.
           enum_sizes: ty::new_ty_hash(),
           discrims: HashMap(),
           discrim_symbols: HashMap(),
diff --git a/src/librustc/middle/trans/build.rs b/src/librustc/middle/trans/build.rs
index e3ffd7a2f9a..98151ff0088 100644
--- a/src/librustc/middle/trans/build.rs
+++ b/src/librustc/middle/trans/build.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use codemap::span;
 use lib::llvm::llvm;
 use lib::llvm::{CallConv, TypeKind, AtomicBinOp, AtomicOrdering};
@@ -53,8 +54,8 @@ fn count_insn(cx: block, category: &str) {
         let mut s = ~".";
         i = 0u;
         while i < len {
-            let e = v[i];
-            i = mm.get(e);
+            let e = /*bad*/copy v[i];
+            i = mm.get(/*bad*/ copy e);
             s += ~"/";
             s += e;
             i += 1u;
@@ -662,7 +663,7 @@ fn add_span_comment(bcx: block, sp: span, text: ~str) {
     if !ccx.sess.no_asm_comments() {
         let s = text + ~" (" + ccx.sess.codemap.span_to_str(sp)
             + ~")";
-        log(debug, s);
+        log(debug, copy s);
         add_comment(bcx, s);
     }
 }
diff --git a/src/librustc/middle/trans/callee.rs b/src/librustc/middle/trans/callee.rs
index de020395396..88f908c4c26 100644
--- a/src/librustc/middle/trans/callee.rs
+++ b/src/librustc/middle/trans/callee.rs
@@ -16,6 +16,7 @@
 // and methods are represented as just a fn ptr and not a full
 // closure.
 
+
 use lib::llvm::ValueRef;
 use middle::trans::base::{get_item_val, trans_external_path};
 use middle::trans::build::*;
@@ -159,7 +160,7 @@ fn trans_fn_ref(bcx: block,
 fn trans_fn_ref_with_vtables_to_callee(bcx: block,
                                        def_id: ast::def_id,
                                        ref_id: ast::node_id,
-                                       type_params: ~[ty::t],
+                                       +type_params: ~[ty::t],
                                        vtables: Option<typeck::vtable_res>)
     -> Callee
 {
@@ -172,7 +173,7 @@ fn trans_fn_ref_with_vtables(
     bcx: block,            //
     def_id: ast::def_id,   // def id of fn
     ref_id: ast::node_id,  // node id of use of fn; may be zero if N/A
-    type_params: ~[ty::t], // values for fn's ty params
+    +type_params: ~[ty::t], // values for fn's ty params
     vtables: Option<typeck::vtable_res>)
     -> FnData
 {
@@ -415,7 +416,7 @@ fn trans_call_inner(
     autoref_arg: AutorefArg) -> block
 {
     do base::with_scope(in_cx, call_info, ~"call") |cx| {
-        let ret_in_loop = match args {
+        let ret_in_loop = match /*bad*/copy args {
           ArgExprs(args) => {
             args.len() > 0u && match vec::last(args).node {
               ast::expr_loop_body(@{
@@ -459,10 +460,10 @@ fn trans_call_inner(
             }
         };
 
-        let args_res = trans_args(bcx, llenv, args, fn_expr_ty,
+        let args_res = trans_args(bcx, llenv, /*bad*/copy args, fn_expr_ty,
                                   dest, ret_flag, autoref_arg);
         bcx = args_res.bcx;
-        let mut llargs = args_res.args;
+        let mut llargs = /*bad*/copy args_res.args;
 
         let llretslot = args_res.retslot;
 
@@ -519,8 +520,12 @@ enum CallArgs {
     ArgVals(~[ValueRef])
 }
 
-fn trans_args(cx: block, llenv: ValueRef, args: CallArgs, fn_ty: ty::t,
-              dest: expr::Dest, ret_flag: Option<ValueRef>,
+fn trans_args(cx: block,
+              llenv: ValueRef,
+              +args: CallArgs,
+              fn_ty: ty::t,
+              dest: expr::Dest,
+              ret_flag: Option<ValueRef>,
               +autoref_arg: AutorefArg)
     -> {bcx: block, args: ~[ValueRef], retslot: ValueRef}
 {
@@ -614,14 +619,18 @@ fn trans_arg_expr(bcx: block,
         Some(_) => {
             match arg_expr.node {
                 ast::expr_loop_body(
-                    blk@@{node:ast::expr_fn_block(decl, ref body, cap), _}) =>
+                    // XXX: Bad copy.
+                    blk@@{
+                        node: ast::expr_fn_block(copy decl, ref body, cap),
+                        _
+                    }) =>
                 {
                     let scratch_ty = expr_ty(bcx, blk);
                     let scratch = alloc_ty(bcx, scratch_ty);
                     let arg_ty = expr_ty(bcx, arg_expr);
                     let proto = ty::ty_fn_proto(arg_ty);
                     let bcx = closure::trans_expr_fn(
-                        bcx, proto, decl, (*body), blk.id, cap,
+                        bcx, proto, decl, /*bad*/copy *body, blk.id, cap,
                         Some(ret_flag), expr::SaveIn(scratch));
                     DatumBlock {bcx: bcx,
                                 datum: Datum {val: scratch,
diff --git a/src/librustc/middle/trans/closure.rs b/src/librustc/middle/trans/closure.rs
index 353f1100cc9..6a0c2aceda3 100644
--- a/src/librustc/middle/trans/closure.rs
+++ b/src/librustc/middle/trans/closure.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::abi;
 use back::link::{mangle_internal_name_by_path_and_seq};
 use back::link::{mangle_internal_name_by_path};
@@ -211,7 +212,8 @@ fn store_environment(bcx: block,
     let ccx = bcx.ccx(), tcx = ccx.tcx;
 
     // compute the shape of the closure
-    let cdata_ty = mk_closure_tys(tcx, bound_values);
+    // XXX: Bad copy.
+    let cdata_ty = mk_closure_tys(tcx, copy bound_values);
 
     // allocate closure in the heap
     let Result {bcx: bcx, val: llbox} = allocate_cbox(bcx, proto, cdata_ty);
@@ -374,8 +376,8 @@ fn load_environment(fcx: fn_ctxt,
 
 fn trans_expr_fn(bcx: block,
                  proto: ast::Proto,
-                 decl: ast::fn_decl,
-                 body: ast::blk,
+                 +decl: ast::fn_decl,
+                 +body: ast::blk,
                  id: ast::node_id,
                  cap_clause: ast::capture_clause,
                  is_loop_body: Option<Option<ValueRef>>,
@@ -392,19 +394,24 @@ fn trans_expr_fn(bcx: block,
     let ccx = bcx.ccx();
     let fty = node_id_type(bcx, id);
     let llfnty = type_of_fn_from_ty(ccx, fty);
-    let sub_path = vec::append_one(bcx.fcx.path,
+    let sub_path = vec::append_one(/*bad*/copy bcx.fcx.path,
                                    path_name(special_idents::anon));
-    let s = mangle_internal_name_by_path_and_seq(ccx, sub_path, ~"expr_fn");
+    // XXX: Bad copy.
+    let s = mangle_internal_name_by_path_and_seq(ccx,
+                                                 copy sub_path,
+                                                 ~"expr_fn");
     let llfn = decl_internal_cdecl_fn(ccx.llmod, s, llfnty);
 
-    let trans_closure_env = fn@(proto: ast::Proto) -> Result {
+    // XXX: Bad copies.
+    let trans_closure_env = |proto, copy body, copy sub_path, copy decl| {
         let cap_vars = capture::compute_capture_vars(ccx.tcx, id, proto,
                                                      cap_clause);
         let ret_handle = match is_loop_body { Some(x) => x, None => None };
-        let {llbox, cdata_ty, bcx} = build_closure(bcx, cap_vars, proto,
+        // XXX: Bad copy.
+        let {llbox, cdata_ty, bcx} = build_closure(bcx, copy cap_vars, proto,
                                                    ret_handle);
-        trans_closure(ccx, sub_path, decl, body, llfn, no_self,
-                      bcx.fcx.param_substs, id, None, |fcx| {
+        trans_closure(ccx, /*bad*/copy sub_path, decl, body, llfn, no_self,
+                      /*bad*/copy bcx.fcx.param_substs, id, None, |fcx| {
             load_environment(fcx, cdata_ty, cap_vars,
                              ret_handle.is_some(), proto);
                       }, |bcx| {
diff --git a/src/librustc/middle/trans/common.rs b/src/librustc/middle/trans/common.rs
index 50810129569..ee2028200e4 100644
--- a/src/librustc/middle/trans/common.rs
+++ b/src/librustc/middle/trans/common.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 /**
    Code that is useful in various trans modules.
 
@@ -59,7 +60,10 @@ use syntax::{ast, ast_map};
 type namegen = fn@(~str) -> ident;
 fn new_namegen(intr: @ident_interner) -> namegen {
     return fn@(prefix: ~str) -> ident {
-        return intr.gensym(@fmt!("%s_%u", prefix, intr.gensym(@prefix).repr))
+        // XXX: Bad copies.
+        return intr.gensym(@fmt!("%s_%u",
+                                 prefix,
+                                 intr.gensym(@copy prefix).repr))
     };
 }
 
@@ -470,7 +474,7 @@ fn revoke_clean(cx: block, val: ValueRef) {
 fn block_cleanups(bcx: block) -> ~[cleanup] {
     match bcx.kind {
        block_non_scope  => ~[],
-       block_scope(ref inf) => (*inf).cleanups
+       block_scope(ref inf) => /*bad*/copy inf.cleanups
     }
 }
 
@@ -1077,7 +1081,7 @@ fn C_u8(i: uint) -> ValueRef { return C_integral(T_i8(), i as u64, False); }
 
 // This is a 'c-like' raw string, which differs from
 // our boxed-and-length-annotated strings.
-fn C_cstr(cx: @crate_ctxt, s: ~str) -> ValueRef {
+fn C_cstr(cx: @crate_ctxt, +s: ~str) -> ValueRef {
     match cx.const_cstr_cache.find(s) {
       Some(llval) => return llval,
       None => ()
@@ -1100,9 +1104,10 @@ fn C_cstr(cx: @crate_ctxt, s: ~str) -> ValueRef {
 
 // NB: Do not use `do_spill_noroot` to make this into a constant string, or
 // you will be kicked off fast isel. See issue #4352 for an example of this.
-fn C_estr_slice(cx: @crate_ctxt, s: ~str) -> ValueRef {
+fn C_estr_slice(cx: @crate_ctxt, +s: ~str) -> ValueRef {
+    let len = str::len(s);
     let cs = llvm::LLVMConstPointerCast(C_cstr(cx, s), T_ptr(T_i8()));
-    C_struct(~[cs, C_uint(cx, str::len(s) + 1u /* +1 for null */)])
+    C_struct(~[cs, C_uint(cx, len + 1u /* +1 for null */)])
 }
 
 // Returns a Plain Old LLVM String:
@@ -1149,7 +1154,7 @@ fn C_bytes_plus_null(bytes: ~[u8]) -> ValueRef unsafe {
         bytes.len() as c_uint, False);
 }
 
-fn C_shape(ccx: @crate_ctxt, bytes: ~[u8]) -> ValueRef {
+fn C_shape(ccx: @crate_ctxt, +bytes: ~[u8]) -> ValueRef {
     let llshape = C_bytes_plus_null(bytes);
     let name = fmt!("shape%u", (ccx.names)(~"shape").repr);
     let llglobal = str::as_c_str(name, |buf| {
@@ -1185,19 +1190,20 @@ type mono_id = @mono_id_;
 
 impl mono_param_id : cmp::Eq {
     pure fn eq(&self, other: &mono_param_id) -> bool {
-        match ((*self), (*other)) {
-            (mono_precise(ty_a, ids_a), mono_precise(ty_b, ids_b)) => {
+        match (self, other) {
+            (&mono_precise(ty_a, ref ids_a),
+             &mono_precise(ty_b, ref ids_b)) => {
                 ty_a == ty_b && ids_a == ids_b
             }
-            (mono_any, mono_any) => true,
-            (mono_repr(size_a, align_a, is_float_a, mode_a),
-             mono_repr(size_b, align_b, is_float_b, mode_b)) => {
+            (&mono_any, &mono_any) => true,
+            (&mono_repr(size_a, align_a, is_float_a, mode_a),
+             &mono_repr(size_b, align_b, is_float_b, mode_b)) => {
                 size_a == size_b && align_a == align_b &&
                     is_float_a == is_float_b && mode_a == mode_b
             }
-            (mono_precise(*), _) => false,
-            (mono_any, _) => false,
-            (mono_repr(*), _) => false
+            (&mono_precise(*), _) => false,
+            (&mono_any, _) => false,
+            (&mono_repr(*), _) => false
         }
     }
     pure fn ne(&self, other: &mono_param_id) -> bool { !(*self).eq(other) }
@@ -1212,7 +1218,7 @@ impl mono_id_ : cmp::Eq {
 
 impl mono_param_id : to_bytes::IterBytes {
     pure fn iter_bytes(&self, +lsb0: bool, f: to_bytes::Cb) {
-        match *self {
+        match /*bad*/copy *self {
           mono_precise(t, mids) =>
           to_bytes::iter_bytes_3(&0u8, &ty::type_id(t), &mids, lsb0, f),
 
@@ -1261,7 +1267,7 @@ fn path_str(sess: session::Session, p: path) -> ~str {
 }
 
 fn monomorphize_type(bcx: block, t: ty::t) -> ty::t {
-    match bcx.fcx.param_substs {
+    match /*bad*/copy bcx.fcx.param_substs {
         Some(substs) => {
             ty::subst_tps(bcx.tcx(), substs.tys, substs.self_ty, t)
         }
@@ -1282,7 +1288,7 @@ fn expr_ty(bcx: block, ex: @ast::expr) -> ty::t {
 fn node_id_type_params(bcx: block, id: ast::node_id) -> ~[ty::t] {
     let tcx = bcx.tcx();
     let params = ty::node_id_to_type_params(tcx, id);
-    match bcx.fcx.param_substs {
+    match /*bad*/copy bcx.fcx.param_substs {
       Some(substs) => {
         do vec::map(params) |t| {
             ty::subst_tps(tcx, substs.tys, substs.self_ty, *t)
@@ -1306,13 +1312,13 @@ fn resolve_vtables_in_fn_ctxt(fcx: fn_ctxt, vts: typeck::vtable_res)
 
 // Apply the typaram substitutions in the fn_ctxt to a vtable. This should
 // eliminate any vtable_params.
-fn resolve_vtable_in_fn_ctxt(fcx: fn_ctxt, vt: typeck::vtable_origin)
+fn resolve_vtable_in_fn_ctxt(fcx: fn_ctxt, +vt: typeck::vtable_origin)
     -> typeck::vtable_origin
 {
     let tcx = fcx.ccx.tcx;
     match vt {
         typeck::vtable_static(trait_id, tys, sub) => {
-            let tys = match fcx.param_substs {
+            let tys = match /*bad*/copy fcx.param_substs {
                 Some(substs) => {
                     do vec::map(tys) |t| {
                         ty::subst_tps(tcx, substs.tys, substs.self_ty, *t)
@@ -1330,12 +1336,12 @@ fn resolve_vtable_in_fn_ctxt(fcx: fn_ctxt, vt: typeck::vtable_origin)
                 }
                 _ => {
                     tcx.sess.bug(fmt!(
-                        "resolve_vtable_in_fn_ctxt: asked to lookup %? but \
-                         no vtables in the fn_ctxt!", vt))
+                        "resolve_vtable_in_fn_ctxt: asked to lookup but \
+                         no vtables in the fn_ctxt!"))
                 }
             }
         }
-        _ => vt
+        vt => vt
     }
 }
 
@@ -1352,10 +1358,10 @@ fn find_vtable(tcx: ty::ctxt, ps: &param_substs,
     let vtables_to_skip =
         ty::count_traits_and_supertraits(tcx, first_n_bounds);
     let vtable_off = vtables_to_skip + n_bound;
-    ps.vtables.get()[vtable_off]
+    /*bad*/ copy ps.vtables.get()[vtable_off]
 }
 
-fn dummy_substs(tps: ~[ty::t]) -> ty::substs {
+fn dummy_substs(+tps: ~[ty::t]) -> ty::substs {
     {self_r: Some(ty::re_bound(ty::br_self)),
      self_ty: None,
      tps: tps}
diff --git a/src/librustc/middle/trans/consts.rs b/src/librustc/middle/trans/consts.rs
index 2d0ac47fd77..0d698b2871d 100644
--- a/src/librustc/middle/trans/consts.rs
+++ b/src/librustc/middle/trans/consts.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::const_eval;
 use middle::trans::base::get_insn_ctxt;
 use middle::trans::common::*;
@@ -36,12 +37,12 @@ fn const_lit(cx: @crate_ctxt, e: @ast::expr, lit: ast::lit)
                                 ~"integer literal doesn't have a type")
         }
       }
-      ast::lit_float(fs, t) => C_floating(*fs, T_float_ty(cx, t)),
+      ast::lit_float(fs, t) => C_floating(/*bad*/copy *fs, T_float_ty(cx, t)),
       ast::lit_float_unsuffixed(fs) => {
         let lit_float_ty = ty::node_id_to_type(cx.tcx, e.id);
         match ty::get(lit_float_ty).sty {
           ty::ty_float(t) => {
-            C_floating(*fs, T_float_ty(cx, t))
+            C_floating(/*bad*/copy *fs, T_float_ty(cx, t))
           }
           _ => {
             cx.sess.span_bug(lit.span,
@@ -52,7 +53,7 @@ fn const_lit(cx: @crate_ctxt, e: @ast::expr, lit: ast::lit)
       }
       ast::lit_bool(b) => C_bool(b),
       ast::lit_nil => C_nil(),
-      ast::lit_str(s) => C_estr_slice(cx, *s)
+      ast::lit_str(s) => C_estr_slice(cx, /*bad*/copy *s)
     }
 }
 
@@ -129,7 +130,7 @@ fn get_const_val(cx: @crate_ctxt, def_id: ast::def_id) -> ValueRef {
 
 fn const_expr(cx: @crate_ctxt, e: @ast::expr) -> ValueRef {
     let _icx = cx.insn_ctxt("const_expr");
-    return match e.node {
+    return match /*bad*/copy e.node {
       ast::expr_lit(lit) => consts::const_lit(cx, e, *lit),
       ast::expr_binary(b, e1, e2) => {
         let te1 = const_expr(cx, e1);
@@ -358,7 +359,7 @@ fn const_expr(cx: @crate_ctxt, e: @ast::expr) -> ValueRef {
         const_expr(cx, e)
       }
       ast::expr_vstore(sub, ast::expr_vstore_slice) => {
-        match sub.node {
+        match /*bad*/copy sub.node {
           ast::expr_lit(lit) => {
             match lit.node {
               ast::lit_str(*) => { const_expr(cx, sub) }
diff --git a/src/librustc/middle/trans/controlflow.rs b/src/librustc/middle/trans/controlflow.rs
index 11cd0925d1a..7ae3fbcd1b8 100644
--- a/src/librustc/middle/trans/controlflow.rs
+++ b/src/librustc/middle/trans/controlflow.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use lib::llvm::ValueRef;
 use middle::trans::base::*;
 use middle::trans::callee;
@@ -171,13 +172,15 @@ fn trans_log(log_ex: @ast::expr,
     }
 
     let modpath = vec::append(
-        ~[path_mod(ccx.sess.ident_of(ccx.link_meta.name))],
+        ~[path_mod(ccx.sess.ident_of(/*bad*/copy ccx.link_meta.name))],
         vec::filter(bcx.fcx.path, |e|
             match *e { path_mod(_) => true, _ => false }
         ));
-    let modname = path_str(ccx.sess, modpath);
+    // XXX: Bad copy.
+    let modname = path_str(ccx.sess, copy modpath);
 
-    let global = if ccx.module_data.contains_key(modname) {
+    // XXX: Bad copy.
+    let global = if ccx.module_data.contains_key(copy modname) {
         ccx.module_data.get(modname)
     } else {
         let s = link::mangle_internal_name_by_path_and_seq(
@@ -310,7 +313,7 @@ fn trans_check_expr(bcx: block, chk_expr: @ast::expr,
         }
     };
     do with_cond(bcx, Not(bcx, val)) |bcx| {
-        trans_fail(bcx, Some(pred_expr.span), expr_str)
+        trans_fail(bcx, Some(pred_expr.span), /*bad*/copy expr_str)
     }
 }
 
@@ -340,7 +343,7 @@ fn trans_fail_expr(bcx: block,
     }
 }
 
-fn trans_fail(bcx: block, sp_opt: Option<span>, fail_str: ~str)
+fn trans_fail(bcx: block, sp_opt: Option<span>, +fail_str: ~str)
     -> block
 {
     let _icx = bcx.insn_ctxt("trans_fail");
@@ -357,7 +360,7 @@ fn trans_fail_value(bcx: block, sp_opt: Option<span>, V_fail_str: ValueRef)
       Some(sp) => {
         let sess = bcx.sess();
         let loc = sess.parse_sess.cm.lookup_char_pos(sp.lo);
-        {V_filename: C_cstr(bcx.ccx(), loc.file.name),
+        {V_filename: C_cstr(bcx.ccx(), /*bad*/copy loc.file.name),
          V_line: loc.line as int}
       }
       None => {
@@ -381,7 +384,7 @@ fn trans_fail_bounds_check(bcx: block, sp: span,
 
     let loc = bcx.sess().parse_sess.cm.lookup_char_pos(sp.lo);
     let line = C_int(ccx, loc.line as int);
-    let filename_cstr = C_cstr(bcx.ccx(), loc.file.name);
+    let filename_cstr = C_cstr(bcx.ccx(), /*bad*/copy loc.file.name);
     let filename = PointerCast(bcx, filename_cstr, T_ptr(T_i8()));
 
     let args = ~[filename, line, index, len];
diff --git a/src/librustc/middle/trans/datum.rs b/src/librustc/middle/trans/datum.rs
index 1723c0bddd3..5c13364ddeb 100644
--- a/src/librustc/middle/trans/datum.rs
+++ b/src/librustc/middle/trans/datum.rs
@@ -95,6 +95,7 @@
  * methods themselves.  Most are only suitable for some types of
  * values. */
 
+
 use lib::llvm::ValueRef;
 use middle::trans::base::*;
 use middle::trans::build::*;
diff --git a/src/librustc/middle/trans/debuginfo.rs b/src/librustc/middle/trans/debuginfo.rs
index ed188a7019e..78d19e9e0cb 100644
--- a/src/librustc/middle/trans/debuginfo.rs
+++ b/src/librustc/middle/trans/debuginfo.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use driver::session;
 use lib::llvm::ValueRef;
 use lib::llvm::llvm;
@@ -107,7 +108,7 @@ type debug_ctxt = {
     crate_file: ~str
 };
 
-fn mk_ctxt(crate: ~str, intr: @ident_interner) -> debug_ctxt {
+fn mk_ctxt(+crate: ~str, intr: @ident_interner) -> debug_ctxt {
     {llmetadata: map::HashMap(),
      names: new_namegen(intr),
      crate_file: crate}
@@ -181,7 +182,7 @@ fn cached_metadata<T: Copy>(cache: metadata_cache, mdtag: int,
 fn create_compile_unit(cx: @crate_ctxt)
     -> @metadata<compile_unit_md> unsafe {
     let cache = get_cache(cx);
-    let crate_name = cx.dbg_cx.get().crate_file;
+    let crate_name = /*bad*/copy (/*bad*/copy cx.dbg_cx).get().crate_file;
     let tg = CompileUnitTag;
     match cached_metadata::<@metadata<compile_unit_md>>(cache, tg,
                         |md| md.data.name == crate_name) {
@@ -194,7 +195,7 @@ fn create_compile_unit(cx: @crate_ctxt)
     let unit_metadata = ~[lltag(tg),
                          llunused(),
                          lli32(DW_LANG_RUST),
-                         llstr(crate_name),
+                         llstr(copy crate_name),
                          llstr(work_dir),
                          llstr(env!("CFG_VERSION")),
                          lli1(true), // deprecated: main compile unit
@@ -211,7 +212,7 @@ fn create_compile_unit(cx: @crate_ctxt)
 }
 
 fn get_cache(cx: @crate_ctxt) -> metadata_cache {
-    cx.dbg_cx.get().llmetadata
+    (/*bad*/copy cx.dbg_cx).get().llmetadata
 }
 
 fn get_file_path_and_dir(work_dir: &str, full_path: &str) -> (~str, ~str) {
@@ -223,7 +224,7 @@ fn get_file_path_and_dir(work_dir: &str, full_path: &str) -> (~str, ~str) {
     }, str::from_slice(work_dir))
 }
 
-fn create_file(cx: @crate_ctxt, full_path: ~str) -> @metadata<file_md> {
+fn create_file(cx: @crate_ctxt, +full_path: ~str) -> @metadata<file_md> {
     let cache = get_cache(cx);;
     let tg = FileDescriptorTag;
     match cached_metadata::<@metadata<file_md>>(
@@ -262,7 +263,7 @@ fn create_block(cx: block) -> @metadata<block_md> {
     let sp = cx.node_info.get().span;
 
     let start = cx.sess().codemap.lookup_char_pos(sp.lo);
-    let fname = start.file.name;
+    let fname = /*bad*/copy start.file.name;
     let end = cx.sess().codemap.lookup_char_pos(sp.hi);
     let tg = LexicalBlockTag;
     /*alt cached_metadata::<@metadata<block_md>>(
@@ -365,12 +366,18 @@ type struct_ctxt = {
 };
 
 fn finish_structure(cx: @struct_ctxt) -> ValueRef {
-    return create_composite_type(StructureTypeTag, cx.name, cx.file, cx.line,
-                              cx.total_size, cx.align, 0, option::None,
-                              option::Some(cx.members));
-}
-
-fn create_structure(file: @metadata<file_md>, name: ~str, line: int)
+    return create_composite_type(StructureTypeTag,
+                                 /*bad*/copy cx.name,
+                                 cx.file,
+                                 cx.line,
+                                 cx.total_size,
+                                 cx.align,
+                                 0,
+                                 option::None,
+                                 option::Some(/*bad*/copy cx.members));
+}
+
+fn create_structure(file: @metadata<file_md>, +name: ~str, line: int)
     -> @struct_ctxt {
     let cx = @{file: file.node,
                name: name,
@@ -382,7 +389,7 @@ fn create_structure(file: @metadata<file_md>, name: ~str, line: int)
     return cx;
 }
 
-fn create_derived_type(type_tag: int, file: ValueRef, name: ~str, line: int,
+fn create_derived_type(type_tag: int, file: ValueRef, +name: ~str, line: int,
                        size: int, align: int, offset: int, ty: ValueRef)
     -> ValueRef {
     let lldata = ~[lltag(type_tag),
@@ -398,7 +405,7 @@ fn create_derived_type(type_tag: int, file: ValueRef, name: ~str, line: int,
     return llmdnode(lldata);
 }
 
-fn add_member(cx: @struct_ctxt, name: ~str, line: int, size: int, align: int,
+fn add_member(cx: @struct_ctxt, +name: ~str, line: int, size: int, align: int,
               ty: ValueRef) {
     cx.members.push(create_derived_type(MemberTag, cx.file, name, line,
                                        size * 8, align * 8, cx.total_size,
@@ -412,7 +419,8 @@ fn create_record(cx: @crate_ctxt, t: ty::t, fields: ~[ast::ty_field],
     let file_node = create_file(cx, fname);
     let scx = create_structure(file_node,
                                cx.sess.str_of(
-                                   (cx.dbg_cx.get().names)(~"rec")),
+                                   ((/*bad*/copy cx.dbg_cx).get().names)
+                                   (~"rec")),
                                line_from_span(cx.sess.codemap,
                                               span) as int);
     for fields.each |field| {
@@ -455,10 +463,10 @@ fn create_boxed_type(cx: @crate_ctxt, outer: ty::t, _inner: ty::t,
     return mdval;
 }
 
-fn create_composite_type(type_tag: int, name: ~str, file: ValueRef, line: int,
-                         size: int, align: int, offset: int,
+fn create_composite_type(type_tag: int, +name: ~str, file: ValueRef,
+                         line: int, size: int, align: int, offset: int,
                          derived: Option<ValueRef>,
-                         members: Option<~[ValueRef]>)
+                         +members: Option<~[ValueRef]>)
     -> ValueRef {
     let lldata = ~[lltag(type_tag),
                   file,
@@ -614,10 +622,10 @@ fn create_ty(_cx: @crate_ctxt, _t: ty::t, _ty: @ast::Ty)
 }
 
 fn filename_from_span(cx: @crate_ctxt, sp: codemap::span) -> ~str {
-    cx.sess.codemap.lookup_char_pos(sp.lo).file.name
+    /*bad*/copy cx.sess.codemap.lookup_char_pos(sp.lo).file.name
 }
 
-fn create_var(type_tag: int, context: ValueRef, name: ~str, file: ValueRef,
+fn create_var(type_tag: int, context: ValueRef, +name: ~str, file: ValueRef,
               line: int, ret_ty: ValueRef) -> ValueRef {
     let lldata = ~[lltag(type_tag),
                   context,
@@ -649,7 +657,7 @@ fn create_local_var(bcx: block, local: @ast::local)
     let loc = cx.sess.codemap.lookup_char_pos(local.span.lo);
     let ty = node_id_type(bcx, local.node.id);
     let tymd = create_ty(cx, ty, local.node.ty);
-    let filemd = create_file(cx, loc.file.name);
+    let filemd = create_file(cx, /*bad*/copy loc.file.name);
     let context = match bcx.parent {
         None => create_function(bcx.fcx).node,
         Some(_) => create_block(bcx).node
@@ -693,7 +701,7 @@ fn create_arg(bcx: block, arg: ast::arg, sp: span)
     let loc = cx.sess.codemap.lookup_char_pos(sp.lo);
     let ty = node_id_type(bcx, arg.id);
     let tymd = create_ty(cx, ty, arg.ty);
-    let filemd = create_file(cx, loc.file.name);
+    let filemd = create_file(cx, /*bad*/copy loc.file.name);
     let context = create_function(bcx.fcx);
 
     match arg.pat.node {
@@ -740,7 +748,7 @@ fn update_source_pos(cx: block, s: span) {
 
 fn create_function(fcx: fn_ctxt) -> @metadata<subprogram_md> {
     let cx = fcx.ccx;
-    let dbg_cx = cx.dbg_cx.get();
+    let dbg_cx = (/*bad*/copy cx.dbg_cx).get();
 
     debug!("~~");
     log(debug, fcx.id);
@@ -750,7 +758,7 @@ fn create_function(fcx: fn_ctxt) -> @metadata<subprogram_md> {
 
     let (ident, ret_ty, id) = match cx.tcx.items.get(fcx.id) {
       ast_map::node_item(item, _) => {
-        match item.node {
+        match /*bad*/copy item.node {
           ast::item_fn(decl, _, _, _) => {
             (item.ident, decl.output, item.id)
           }
@@ -762,7 +770,7 @@ fn create_function(fcx: fn_ctxt) -> @metadata<subprogram_md> {
           (method.ident, method.decl.output, method.id)
       }
       ast_map::node_expr(expr) => {
-        match expr.node {
+        match /*bad*/copy expr.node {
           ast::expr_fn(_, decl, _, _) => {
             ((dbg_cx.names)(~"fn"), decl.output, expr.id)
           }
diff --git a/src/librustc/middle/trans/expr.rs b/src/librustc/middle/trans/expr.rs
index d3a1772a6b0..d2254097106 100644
--- a/src/librustc/middle/trans/expr.rs
+++ b/src/librustc/middle/trans/expr.rs
@@ -111,6 +111,7 @@ lvalues are *never* stored by value.
 
 */
 
+
 use lib::llvm::ValueRef;
 use middle::resolve;
 use middle::trans::base::*;
@@ -514,7 +515,8 @@ fn trans_rvalue_dps_unadjusted(bcx: block, expr: @ast::expr,
 
     trace_span!(bcx, expr.span, shorten(bcx.expr_to_str(expr)));
 
-    match expr.node {
+    // XXX: This copy is really bad.
+    match /*bad*/copy expr.node {
         ast::expr_paren(e) => {
             return trans_rvalue_dps_unadjusted(bcx, e, dest);
         }
@@ -526,7 +528,7 @@ fn trans_rvalue_dps_unadjusted(bcx: block, expr: @ast::expr,
             return controlflow::trans_if(bcx, cond, (*thn), els, dest);
         }
         ast::expr_match(discr, ref arms) => {
-            return alt::trans_alt(bcx, expr, discr, (*arms), dest);
+            return alt::trans_alt(bcx, expr, discr, /*bad*/copy *arms, dest);
         }
         ast::expr_block(ref blk) => {
             return do base::with_scope(bcx, (*blk).info(),
@@ -554,13 +556,14 @@ fn trans_rvalue_dps_unadjusted(bcx: block, expr: @ast::expr,
         ast::expr_vec(*) | ast::expr_repeat(*) => {
             return tvec::trans_fixed_vstore(bcx, expr, expr, dest);
         }
-        ast::expr_fn(proto, decl, ref body, cap_clause) => {
+        // XXX: Bad copy.
+        ast::expr_fn(proto, copy decl, ref body, cap_clause) => {
             // Don't use this function for anything real. Use the one in
             // astconv instead.
-            return closure::trans_expr_fn(bcx, proto, decl, *body, expr.id,
-                                          cap_clause, None, dest);
+            return closure::trans_expr_fn(bcx, proto, decl, /*bad*/copy *body,
+                                          expr.id, cap_clause, None, dest);
         }
-        ast::expr_fn_block(decl, ref body, cap_clause) => {
+        ast::expr_fn_block(ref decl, ref body, cap_clause) => {
             let expr_ty = expr_ty(bcx, expr);
             match ty::get(expr_ty).sty {
                 ty::ty_fn(ref fn_ty) => {
@@ -568,7 +571,8 @@ fn trans_rvalue_dps_unadjusted(bcx: block, expr: @ast::expr,
                            expr_to_str(expr, tcx.sess.intr()),
                            ty_to_str(tcx, expr_ty));
                     return closure::trans_expr_fn(
-                        bcx, fn_ty.meta.proto, decl, *body, expr.id,
+                        bcx, fn_ty.meta.proto, /*bad*/copy *decl,
+                        /*bad*/copy *body, expr.id,
                         cap_clause, None, dest);
                 }
                 _ => {
@@ -581,10 +585,16 @@ fn trans_rvalue_dps_unadjusted(bcx: block, expr: @ast::expr,
             match ty::get(expr_ty(bcx, expr)).sty {
                 ty::ty_fn(ref fn_ty) => {
                     match blk.node {
-                        ast::expr_fn_block(decl, ref body, cap) => {
+                        ast::expr_fn_block(copy decl, ref body, cap) => {
                             return closure::trans_expr_fn(
-                                bcx, fn_ty.meta.proto, decl, *body, blk.id,
-                                cap, Some(None), dest);
+                                bcx,
+                                fn_ty.meta.proto,
+                                decl,
+                                /*bad*/copy *body,
+                                blk.id,
+                                cap,
+                                Some(None),
+                                dest);
                         }
                         _ => {
                             bcx.sess().impossible_case(
diff --git a/src/librustc/middle/trans/foreign.rs b/src/librustc/middle/trans/foreign.rs
index 91e5429fe23..9777d87513c 100644
--- a/src/librustc/middle/trans/foreign.rs
+++ b/src/librustc/middle/trans/foreign.rs
@@ -11,6 +11,7 @@
 // The classification code for the x86_64 ABI is taken from the clay language
 // https://github.com/jckarter/clay/blob/master/compiler/src/externals.cpp
 
+
 use back::{link, abi};
 use driver::session::arch_x86_64;
 use lib::llvm::{SequentiallyConsistent, Acquire, Release, Xchg};
@@ -441,7 +442,7 @@ fn decl_x86_64_fn(tys: x86_64_tys,
 fn link_name(ccx: @crate_ctxt, i: @ast::foreign_item) -> ~str {
     match attr::first_attr_value_str_by_name(i.attrs, ~"link_name") {
         None => ccx.sess.str_of(i.ident),
-        option::Some(ref ln) => (*ln)
+        option::Some(ref ln) => (/*bad*/copy *ln)
     }
 }
 
@@ -458,7 +459,9 @@ fn c_arg_and_ret_lltys(ccx: @crate_ctxt,
                        id: ast::node_id) -> (~[TypeRef], TypeRef, ty::t) {
     match ty::get(ty::node_id_to_type(ccx.tcx, id)).sty {
         ty::ty_fn(ref fn_ty) => {
-            let llargtys = type_of_explicit_args(ccx, fn_ty.sig.inputs);
+            let llargtys = type_of_explicit_args(
+                ccx,
+                /*bad*/copy fn_ty.sig.inputs);
             let llretty = type_of::type_of(ccx, fn_ty.sig.output);
             (llargtys, llretty, fn_ty.sig.output)
         }
@@ -469,7 +472,8 @@ fn c_arg_and_ret_lltys(ccx: @crate_ctxt,
 fn c_stack_tys(ccx: @crate_ctxt,
                id: ast::node_id) -> @c_stack_tys {
     let (llargtys, llretty, ret_ty) = c_arg_and_ret_lltys(ccx, id);
-    let bundle_ty = T_struct(vec::append_one(llargtys, T_ptr(llretty)));
+    // XXX: Bad copy.
+    let bundle_ty = T_struct(vec::append_one(copy llargtys, T_ptr(llretty)));
     let ret_def = !ty::type_is_bot(ret_ty) && !ty::type_is_nil(ret_ty);
     let x86_64 = if ccx.sess.targ_cfg.arch == arch_x86_64 {
         option::Some(x86_64_tys(llargtys, llretty, ret_def))
@@ -493,7 +497,7 @@ type shim_ret_builder = fn(bcx: block, tys: @c_stack_tys,
                            llargbundle: ValueRef, llretval: ValueRef);
 
 fn build_shim_fn_(ccx: @crate_ctxt,
-                  shim_name: ~str,
+                  +shim_name: ~str,
                   llbasefn: ValueRef,
                   tys: @c_stack_tys,
                   cc: lib::llvm::CallConv,
@@ -615,8 +619,8 @@ fn trans_foreign_mod(ccx: @crate_ctxt,
 
             match tys.x86_64_tys {
                 Some(ref x86_64) => {
-                    let mut atys = (*x86_64).arg_tys;
-                    let mut attrs = (*x86_64).attrs;
+                    let mut atys = /*bad*/copy (*x86_64).arg_tys;
+                    let mut attrs = /*bad*/copy (*x86_64).attrs;
                     if (*x86_64).sret {
                         let llretptr = GEPi(bcx, llargbundle, [0u, n]);
                         let llretloc = Load(bcx, llretptr);
@@ -696,24 +700,24 @@ fn trans_foreign_mod(ccx: @crate_ctxt,
         }
 
         let lname = link_name(ccx, foreign_item);
-        let llbasefn = base_fn(ccx, lname, tys, cc);
+        let llbasefn = base_fn(ccx, copy lname, tys, cc);
         // Name the shim function
         let shim_name = lname + ~"__c_stack_shim";
         return build_shim_fn_(ccx, shim_name, llbasefn, tys, cc,
                            build_args, build_ret);
     }
 
-    fn base_fn(ccx: @crate_ctxt, lname: ~str, tys: @c_stack_tys,
+    fn base_fn(ccx: @crate_ctxt, +lname: ~str, tys: @c_stack_tys,
                cc: lib::llvm::CallConv) -> ValueRef {
         // Declare the "prototype" for the base function F:
         match tys.x86_64_tys {
           Some(ref x86_64) => {
             do decl_x86_64_fn((*x86_64)) |fnty| {
-                decl_fn(ccx.llmod, lname, cc, fnty)
+                decl_fn(ccx.llmod, /*bad*/copy lname, cc, fnty)
             }
           }
           _ => {
-            let llbasefnty = T_fn(tys.arg_tys, tys.ret_ty);
+            let llbasefnty = T_fn(/*bad*/copy tys.arg_tys, tys.ret_ty);
             decl_fn(ccx.llmod, lname, cc, llbasefnty)
           }
         }
@@ -786,7 +790,7 @@ fn trans_foreign_mod(ccx: @crate_ctxt,
           if abi != ast::foreign_abi_rust_intrinsic {
               let llwrapfn = get_item_val(ccx, id);
               let tys = c_stack_tys(ccx, id);
-              if attr::attrs_contains_name(foreign_item.attrs,
+              if attr::attrs_contains_name(/*bad*/copy foreign_item.attrs,
                                            ~"rust_stack") {
                   build_direct_fn(ccx, llwrapfn, *foreign_item, tys, cc);
               } else {
@@ -806,13 +810,14 @@ fn trans_foreign_mod(ccx: @crate_ctxt,
 }
 
 fn trans_intrinsic(ccx: @crate_ctxt, decl: ValueRef, item: @ast::foreign_item,
-                   path: ast_map::path, substs: param_substs,
+                   +path: ast_map::path, +substs: param_substs,
                    ref_id: Option<ast::node_id>)
 {
     debug!("trans_intrinsic(item.ident=%s)", ccx.sess.str_of(item.ident));
 
+    // XXX: Bad copy.
     let fcx = new_fn_ctxt_w_id(ccx, path, decl, item.id, None,
-                               Some(substs), Some(item.span));
+                               Some(copy substs), Some(item.span));
     let mut bcx = top_scope_block(fcx, None), lltop = bcx.llbb;
     match ccx.sess.str_of(item.ident) {
         ~"atomic_cxchg" => {
@@ -1292,18 +1297,19 @@ fn trans_intrinsic(ccx: @crate_ctxt, decl: ValueRef, item: @ast::foreign_item,
     finish_fn(fcx, lltop);
 }
 
-fn trans_foreign_fn(ccx: @crate_ctxt, path: ast_map::path, decl: ast::fn_decl,
-                  body: ast::blk, llwrapfn: ValueRef, id: ast::node_id) {
-
+fn trans_foreign_fn(ccx: @crate_ctxt, +path: ast_map::path,
+                    decl: ast::fn_decl, body: ast::blk, llwrapfn: ValueRef,
+                    id: ast::node_id) {
     let _icx = ccx.insn_ctxt("foreign::build_foreign_fn");
 
-    fn build_rust_fn(ccx: @crate_ctxt, path: ast_map::path,
+    fn build_rust_fn(ccx: @crate_ctxt, +path: ast_map::path,
                      decl: ast::fn_decl, body: ast::blk,
                      id: ast::node_id) -> ValueRef {
         let _icx = ccx.insn_ctxt("foreign::foreign::build_rust_fn");
         let t = ty::node_id_to_type(ccx.tcx, id);
+        // XXX: Bad copy.
         let ps = link::mangle_internal_name_by_path(
-            ccx, vec::append_one(path, ast_map::path_name(
+            ccx, vec::append_one(copy path, ast_map::path_name(
                 special_idents::clownshoe_abi
             )));
         let llty = type_of_fn_from_ty(ccx, t);
@@ -1312,9 +1318,8 @@ fn trans_foreign_fn(ccx: @crate_ctxt, path: ast_map::path, decl: ast::fn_decl,
         return llfndecl;
     }
 
-    fn build_shim_fn(ccx: @crate_ctxt, path: ast_map::path,
+    fn build_shim_fn(ccx: @crate_ctxt, +path: ast_map::path,
                      llrustfn: ValueRef, tys: @c_stack_tys) -> ValueRef {
-
         let _icx = ccx.insn_ctxt("foreign::foreign::build_shim_fn");
 
         fn build_args(bcx: block, tys: @c_stack_tys,
@@ -1360,8 +1365,8 @@ fn trans_foreign_fn(ccx: @crate_ctxt, path: ast_map::path, decl: ast::fn_decl,
             let _icx = bcx.insn_ctxt("foreign::foreign::wrap::build_args");
             match tys.x86_64_tys {
                 option::Some(ref x86_64) => {
-                    let mut atys = (*x86_64).arg_tys;
-                    let mut attrs = (*x86_64).attrs;
+                    let mut atys = /*bad*/copy (*x86_64).arg_tys;
+                    let mut attrs = /*bad*/copy (*x86_64).attrs;
                     let mut j = 0u;
                     let llretptr = if (*x86_64).sret {
                         atys = vec::tail(atys);
@@ -1445,16 +1450,19 @@ fn trans_foreign_fn(ccx: @crate_ctxt, path: ast_map::path, decl: ast::fn_decl,
 
     let tys = c_stack_tys(ccx, id);
     // The internal Rust ABI function - runs on the Rust stack
-    let llrustfn = build_rust_fn(ccx, path, decl, body, id);
+    // XXX: Bad copy.
+    let llrustfn = build_rust_fn(ccx, copy path, decl, body, id);
     // The internal shim function - runs on the Rust stack
     let llshimfn = build_shim_fn(ccx, path, llrustfn, tys);
     // The foreign C function - runs on the C stack
     build_wrap_fn(ccx, llshimfn, llwrapfn, tys)
 }
 
-fn register_foreign_fn(ccx: @crate_ctxt, sp: span,
-                     path: ast_map::path, node_id: ast::node_id)
-    -> ValueRef {
+fn register_foreign_fn(ccx: @crate_ctxt,
+                       sp: span,
+                       +path: ast_map::path,
+                       node_id: ast::node_id)
+                    -> ValueRef {
     let _icx = ccx.insn_ctxt("foreign::register_foreign_fn");
     let t = ty::node_id_to_type(ccx.tcx, node_id);
     let (llargtys, llretty, ret_ty) = c_arg_and_ret_lltys(ccx, node_id);
@@ -1462,7 +1470,7 @@ fn register_foreign_fn(ccx: @crate_ctxt, sp: span,
         let ret_def = !ty::type_is_bot(ret_ty) && !ty::type_is_nil(ret_ty);
         let x86_64 = x86_64_tys(llargtys, llretty, ret_def);
         do decl_x86_64_fn(x86_64) |fnty| {
-            register_fn_fuller(ccx, sp, path, node_id,
+            register_fn_fuller(ccx, sp, /*bad*/copy path, node_id,
                                t, lib::llvm::CCallConv, fnty)
         }
     } else {
@@ -1482,7 +1490,9 @@ fn abi_of_foreign_fn(ccx: @crate_ctxt, i: @ast::foreign_item)
       },
       Some(_) => match attr::foreign_abi(i.attrs) {
         either::Right(abi) => abi,
-        either::Left(ref msg) => ccx.sess.span_fatal(i.span, (*msg))
+        either::Left(ref msg) => {
+            ccx.sess.span_fatal(i.span, (/*bad*/copy *msg))
+        }
       }
     }
 }
diff --git a/src/librustc/middle/trans/glue.rs b/src/librustc/middle/trans/glue.rs
index d0950481097..2ea3873ebcd 100644
--- a/src/librustc/middle/trans/glue.rs
+++ b/src/librustc/middle/trans/glue.rs
@@ -12,6 +12,7 @@
 //
 // Code relating to taking, dropping, etc as well as type descriptors.
 
+
 use lib::llvm::{ValueRef, TypeRef};
 use middle::trans::base::*;
 use middle::trans::callee;
@@ -447,7 +448,7 @@ fn trans_struct_drop(bcx: block,
 
         // Find and call the actual destructor
         let dtor_addr = get_res_dtor(bcx.ccx(), dtor_did,
-                                     class_did, substs.tps);
+                                     class_did, /*bad*/copy substs.tps);
 
         // The second argument is the "self" argument for drop
         let params = lib::llvm::fn_ty_param_tys(
@@ -656,7 +657,8 @@ fn declare_tydesc(ccx: @crate_ctxt, t: ty::t) -> @tydesc_info {
     } else {
         mangle_internal_name_by_seq(ccx, ~"tydesc")
     };
-    note_unique_llvm_symbol(ccx, name);
+    // XXX: Bad copy.
+    note_unique_llvm_symbol(ccx, copy name);
     log(debug, fmt!("+++ declare_tydesc %s %s", ty_to_str(ccx.tcx, t), name));
     let gvar = str::as_c_str(name, |buf| {
         llvm::LLVMAddGlobal(ccx.llmod, ccx.tydesc_type, buf)
@@ -678,7 +680,7 @@ fn declare_tydesc(ccx: @crate_ctxt, t: ty::t) -> @tydesc_info {
 type glue_helper = fn@(block, ValueRef, ty::t);
 
 fn declare_generic_glue(ccx: @crate_ctxt, t: ty::t, llfnty: TypeRef,
-                        name: ~str) -> ValueRef {
+                        +name: ~str) -> ValueRef {
     let _icx = ccx.insn_ctxt("declare_generic_glue");
     let name = name;
     let mut fn_nm;
@@ -689,7 +691,8 @@ fn declare_generic_glue(ccx: @crate_ctxt, t: ty::t, llfnty: TypeRef,
         fn_nm = mangle_internal_name_by_seq(ccx, (~"glue_" + name));
     }
     debug!("%s is for type %s", fn_nm, ty_to_str(ccx.tcx, t));
-    note_unique_llvm_symbol(ccx, fn_nm);
+    // XXX: Bad copy.
+    note_unique_llvm_symbol(ccx, copy fn_nm);
     let llfn = decl_cdecl_fn(ccx.llmod, fn_nm, llfnty);
     set_glue_inlining(llfn, t);
     return llfn;
diff --git a/src/librustc/middle/trans/inline.rs b/src/librustc/middle/trans/inline.rs
index d97272b0959..28955f49844 100644
--- a/src/librustc/middle/trans/inline.rs
+++ b/src/librustc/middle/trans/inline.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::astencode;
 use middle::trans::base::{get_insn_ctxt};
 use middle::trans::base::{impl_owned_self, impl_self, no_self};
diff --git a/src/librustc/middle/trans/machine.rs b/src/librustc/middle/trans/machine.rs
index b0573782054..5c7ed2dd0ba 100644
--- a/src/librustc/middle/trans/machine.rs
+++ b/src/librustc/middle/trans/machine.rs
@@ -10,6 +10,7 @@
 
 // Information concerning the machine representation of various types.
 
+
 use middle::trans::common::*;
 use middle::trans::type_of;
 use middle::ty;
@@ -152,8 +153,9 @@ pub fn static_size_of_enum(cx: @crate_ctxt, t: ty::t) -> uint {
         let mut max_size = 0u;
         let variants = ty::enum_variants(cx.tcx, tid);
         for vec::each(*variants) |variant| {
-            let tup_ty = simplify_type(cx.tcx,
-                                       ty::mk_tup(cx.tcx, variant.args));
+            let tup_ty = simplify_type(
+                cx.tcx,
+                ty::mk_tup(cx.tcx, /*bad*/copy variant.args));
             // Perform any type parameter substitutions.
             let tup_ty = ty::subst(cx.tcx, substs, tup_ty);
             // Here we possibly do a recursive call.
diff --git a/src/librustc/middle/trans/macros.rs b/src/librustc/middle/trans/macros.rs
index 99175e09af5..dad4a8bd2bf 100644
--- a/src/librustc/middle/trans/macros.rs
+++ b/src/librustc/middle/trans/macros.rs
@@ -52,4 +52,4 @@ macro_rules! trace(
     )
 );
 
-}
\ No newline at end of file
+}
diff --git a/src/librustc/middle/trans/meth.rs b/src/librustc/middle/trans/meth.rs
index a7c70430675..070a3b667bd 100644
--- a/src/librustc/middle/trans/meth.rs
+++ b/src/librustc/middle/trans/meth.rs
@@ -44,7 +44,7 @@ for non-monomorphized methods only.  Other methods will
 be generated once they are invoked with specific type parameters,
 see `trans::base::lval_static_fn()` or `trans::base::monomorphic_fn()`.
 */
-fn trans_impl(ccx: @crate_ctxt, path: path, name: ast::ident,
+fn trans_impl(ccx: @crate_ctxt, +path: path, name: ast::ident,
               methods: ~[@ast::method], tps: ~[ast::ty_param],
               self_ty: Option<ty::t>, id: ast::node_id) {
     let _icx = ccx.insn_ctxt("impl::trans_impl");
@@ -53,7 +53,8 @@ fn trans_impl(ccx: @crate_ctxt, path: path, name: ast::ident,
     for vec::each(methods) |method| {
         if method.tps.len() == 0u {
             let llfn = get_item_val(ccx, method.id);
-            let path = vec::append_one(sub_path, path_name(method.ident));
+            let path = vec::append_one(/*bad*/copy sub_path,
+                                       path_name(method.ident));
 
             let param_substs_opt;
             match self_ty {
@@ -90,13 +91,12 @@ Translates a (possibly monomorphized) method body.
 - `impl_id`: the node ID of the impl this method is inside
 */
 fn trans_method(ccx: @crate_ctxt,
-                path: path,
+                +path: path,
                 method: &ast::method,
-                param_substs: Option<param_substs>,
+                +param_substs: Option<param_substs>,
                 base_self_ty: Option<ty::t>,
                 llfn: ValueRef,
                 impl_id: ast::def_id) {
-
     // figure out how self is being passed
     let self_arg = match method.self_ty.node {
       ast::sty_static => {
@@ -289,7 +289,7 @@ fn trans_static_method_callee(bcx: block,
     let vtbls = resolve_vtables_in_fn_ctxt(
         bcx.fcx, ccx.maps.vtable_map.get(callee_id));
 
-    match vtbls[bound_index] {
+    match /*bad*/copy vtbls[bound_index] {
         typeck::vtable_static(impl_did, rcvr_substs, rcvr_origins) => {
 
             let mth_id = method_with_name(bcx.ccx(), impl_did, mname);
@@ -325,8 +325,11 @@ fn method_with_name(ccx: @crate_ctxt, impl_id: ast::def_id,
                     name: ast::ident) -> ast::def_id {
     if impl_id.crate == ast::local_crate {
         match ccx.tcx.items.get(impl_id.node) {
-          ast_map::node_item(@{node: ast::item_impl(_, _, _, ms), _}, _) => {
-            method_from_methods(ms, name).get()
+          ast_map::node_item(@{
+                node: ast::item_impl(_, _, _, ref ms),
+                _
+            }, _) => {
+            method_from_methods(/*bad*/copy *ms, name).get()
           }
           _ => fail ~"method_with_name"
         }
@@ -339,8 +342,10 @@ fn method_with_name_or_default(ccx: @crate_ctxt, impl_id: ast::def_id,
                                name: ast::ident) -> ast::def_id {
     if impl_id.crate == ast::local_crate {
         match ccx.tcx.items.get(impl_id.node) {
-          ast_map::node_item(@{node: ast::item_impl(_, _, _, ms), _}, _) => {
-              let did = method_from_methods(ms, name);
+          ast_map::node_item(@{
+                node: ast::item_impl(_, _, _, ref ms), _
+          }, _) => {
+              let did = method_from_methods(/*bad*/copy *ms, name);
               if did.is_some() {
                   return did.get();
               } else {
@@ -400,7 +405,7 @@ fn trans_monomorphized_callee(bcx: block,
                               mentry: typeck::method_map_entry,
                               trait_id: ast::def_id,
                               n_method: uint,
-                              vtbl: typeck::vtable_origin)
+                              +vtbl: typeck::vtable_origin)
     -> Callee
 {
     let _icx = bcx.insn_ctxt("impl::trans_monomorphized_callee");
@@ -462,7 +467,7 @@ fn combine_impl_and_methods_tps(bcx: block,
                                 mth_did: ast::def_id,
                                 impl_did: ast::def_id,
                                 callee_id: ast::node_id,
-                                rcvr_substs: ~[ty::t])
+                                +rcvr_substs: ~[ty::t])
     -> ~[ty::t]
 {
     /*!
@@ -485,12 +490,12 @@ fn combine_impl_and_methods_tps(bcx: block,
     let ccx = bcx.ccx();
     let n_m_tps = method_ty_param_count(ccx, mth_did, impl_did);
     let node_substs = node_id_type_params(bcx, callee_id);
+    debug!("rcvr_substs=%?", rcvr_substs.map(|t| bcx.ty_to_str(*t)));
     let ty_substs
         = vec::append(rcvr_substs,
                       vec::tailn(node_substs,
                                  node_substs.len() - n_m_tps));
     debug!("n_m_tps=%?", n_m_tps);
-    debug!("rcvr_substs=%?", rcvr_substs.map(|t| bcx.ty_to_str(*t)));
     debug!("node_substs=%?", node_substs.map(|t| bcx.ty_to_str(*t)));
     debug!("ty_substs=%?", ty_substs.map(|t| bcx.ty_to_str(*t)));
 
@@ -535,7 +540,7 @@ fn combine_impl_and_methods_origins(bcx: block,
     let m_origins = vec::tailn(*r_m_origins, r_m_origins.len() - m_vtables);
 
     // Combine rcvr + method to find the final result:
-    @vec::append(*rcvr_origins, m_origins)
+    @vec::append(/*bad*/copy *rcvr_origins, m_origins)
 }
 
 
@@ -706,7 +711,7 @@ fn trans_trait_callee_from_llval(bcx: block,
     };
 }
 
-fn vtable_id(ccx: @crate_ctxt, origin: typeck::vtable_origin) -> mono_id {
+fn vtable_id(ccx: @crate_ctxt, +origin: typeck::vtable_origin) -> mono_id {
     match origin {
         typeck::vtable_static(impl_id, substs, sub_vtables) => {
             monomorphize::make_mono_id(
@@ -733,9 +738,9 @@ fn vtable_id(ccx: @crate_ctxt, origin: typeck::vtable_origin) -> mono_id {
     }
 }
 
-fn get_vtable(ccx: @crate_ctxt, origin: typeck::vtable_origin)
-    -> ValueRef {
-    let hash_id = vtable_id(ccx, origin);
+fn get_vtable(ccx: @crate_ctxt, +origin: typeck::vtable_origin) -> ValueRef {
+    // XXX: Bad copy.
+    let hash_id = vtable_id(ccx, copy origin);
     match ccx.vtables.find(hash_id) {
       Some(val) => val,
       None => match origin {
@@ -868,7 +873,7 @@ fn trans_trait_cast(bcx: block,
     }
 
     // Store the vtable into the pair or triple.
-    let orig = ccx.maps.vtable_map.get(id)[0];
+    let orig = /*bad*/copy ccx.maps.vtable_map.get(id)[0];
     let orig = resolve_vtable_in_fn_ctxt(bcx.fcx, orig);
     let vtable = get_vtable(bcx.ccx(), orig);
     Store(bcx, vtable, PointerCast(bcx,
diff --git a/src/librustc/middle/trans/monomorphize.rs b/src/librustc/middle/trans/monomorphize.rs
index f0a21b057c9..4b5fdedb738 100644
--- a/src/librustc/middle/trans/monomorphize.rs
+++ b/src/librustc/middle/trans/monomorphize.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::link::mangle_exported_name;
 use middle::trans::base::{get_insn_ctxt};
 use middle::trans::base::{set_inline_hint_if_appr, set_inline_hint};
@@ -53,7 +54,8 @@ fn monomorphic_fn(ccx: @crate_ctxt,
     for real_substs.each() |s| { assert !ty::type_has_params(*s); }
     for substs.each() |s| { assert !ty::type_has_params(*s); }
     let param_uses = type_use::type_uses_for(ccx, fn_id, substs.len());
-    let hash_id = make_mono_id(ccx, fn_id, substs, vtables, impl_did_opt,
+    // XXX: Bad copy.
+    let hash_id = make_mono_id(ccx, fn_id, copy substs, vtables, impl_did_opt,
                                Some(param_uses));
     if vec::any(hash_id.params,
                 |p| match *p { mono_precise(_, _) => false, _ => true }) {
@@ -146,12 +148,12 @@ fn monomorphic_fn(ccx: @crate_ctxt,
     }
     ccx.monomorphizing.insert(fn_id, depth + 1);
 
-    let pt = vec::append(*pt,
+    let pt = vec::append(/*bad*/copy *pt,
                          ~[path_name((ccx.names)(ccx.sess.str_of(name)))]);
-    let s = mangle_exported_name(ccx, pt, mono_ty);
+    let s = mangle_exported_name(ccx, /*bad*/copy pt, mono_ty);
 
-    let mk_lldecl = || {
-        let lldecl = decl_internal_cdecl_fn(ccx.llmod, s, llfty);
+    let mk_lldecl = |/*bad*/copy s| {
+        let lldecl = decl_internal_cdecl_fn(ccx.llmod, /*bad*/copy s, llfty);
         ccx.monomorphized.insert(hash_id, lldecl);
         lldecl
     };
@@ -165,11 +167,12 @@ fn monomorphic_fn(ccx: @crate_ctxt,
 
     let lldecl = match map_node {
       ast_map::node_item(i@@{
-                node: ast::item_fn(decl, _, _, ref body),
+                // XXX: Bad copy.
+                node: ast::item_fn(copy decl, _, _, ref body),
                 _
             }, _) => {
         let d = mk_lldecl();
-        set_inline_hint_if_appr(i.attrs, d);
+        set_inline_hint_if_appr(/*bad*/copy i.attrs, d);
         trans_fn(ccx, pt, decl, *body, d, no_self, psubsts, fn_id.node, None);
         d
       }
@@ -189,9 +192,9 @@ fn monomorphic_fn(ccx: @crate_ctxt,
         let d = mk_lldecl();
         set_inline_hint(d);
         match (*v).node.kind {
-            ast::tuple_variant_kind(args) => {
-                trans_enum_variant(ccx, enum_item.id, (*v), args,
-                                   this_tv.disr_val, (*tvs).len() == 1u,
+            ast::tuple_variant_kind(ref args) => {
+                trans_enum_variant(ccx, enum_item.id, *v, /*bad*/copy *args,
+                                   this_tv.disr_val, tvs.len() == 1u,
                                    psubsts, d);
             }
             ast::struct_variant_kind(_) =>
@@ -204,7 +207,7 @@ fn monomorphic_fn(ccx: @crate_ctxt,
       ast_map::node_method(mth, supplied_impl_did, _) => {
         // XXX: What should the self type be here?
         let d = mk_lldecl();
-        set_inline_hint_if_appr(mth.attrs, d);
+        set_inline_hint_if_appr(/*bad*/copy mth.attrs, d);
 
         // Override the impl def ID if necessary.
         let impl_did;
@@ -223,14 +226,14 @@ fn monomorphic_fn(ccx: @crate_ctxt,
                 None      => ccx.sess.span_bug(dtor.span, ~"Bad self ty in \
                                                             dtor")
         };
-        trans_struct_dtor(ccx, *pt, dtor.node.body,
+        trans_struct_dtor(ccx, /*bad*/copy *pt, dtor.node.body,
           dtor.node.id, psubsts, Some(hash_id), parent_id)
       }
       ast_map::node_trait_method(@ast::provided(mth), _, pt) => {
         let d = mk_lldecl();
-        set_inline_hint_if_appr(mth.attrs, d);
+        set_inline_hint_if_appr(/*bad*/copy mth.attrs, d);
         debug!("monomorphic_fn impl_did_opt is %?", impl_did_opt);
-        meth::trans_method(ccx, *pt, mth, psubsts, None, d,
+        meth::trans_method(ccx, /*bad*/copy *pt, mth, psubsts, None, d,
                            impl_did_opt.get());
         d
       }
@@ -238,7 +241,7 @@ fn monomorphic_fn(ccx: @crate_ctxt,
         let d = mk_lldecl();
         set_inline_hint(d);
         base::trans_tuple_struct(ccx,
-                                 struct_def.fields,
+                                 /*bad*/copy struct_def.fields,
                                  option::expect(struct_def.ctor_id,
                                                 ~"ast-mapped tuple struct \
                                                   didn't have a ctor id"),
@@ -316,7 +319,7 @@ fn make_mono_id(ccx: @crate_ctxt, item: ast::def_id, substs: ~[ty::t],
             for bounds.each |bound| {
                 match *bound {
                   ty::bound_trait(_) => {
-                    v.push(meth::vtable_id(ccx, vts[i]));
+                    v.push(meth::vtable_id(ccx, /*bad*/copy vts[i]));
                     i += 1u;
                   }
                   _ => ()
@@ -330,15 +333,16 @@ fn make_mono_id(ccx: @crate_ctxt, item: ast::def_id, substs: ~[ty::t],
       }
     };
     let param_ids = match param_uses {
-      Some(uses) => {
-        vec::map2(precise_param_ids, uses, |id, uses| {
+      Some(ref uses) => {
+        vec::map2(precise_param_ids, *uses, |id, uses| {
             if ccx.sess.no_monomorphic_collapse() {
                 match *id {
                     (a, b) => mono_precise(a, b)
                 }
             } else {
                 match *id {
-                    (a, b@Some(_)) => mono_precise(a, b),
+                    // XXX: Bad copy.
+                    (a, copy b@Some(_)) => mono_precise(a, b),
                     (subst, None) => {
                         if *uses == 0u {
                             mono_any
diff --git a/src/librustc/middle/trans/reachable.rs b/src/librustc/middle/trans/reachable.rs
index 7c8b314a96b..832f4f8294e 100644
--- a/src/librustc/middle/trans/reachable.rs
+++ b/src/librustc/middle/trans/reachable.rs
@@ -15,6 +15,7 @@
 // makes all other generics or inline functions that it references
 // reachable as well.
 
+
 use driver::session::*;
 use middle::resolve;
 use middle::ty;
@@ -71,7 +72,7 @@ fn traverse_def_id(cx: ctx, did: def_id) {
     if did.crate != local_crate { return; }
     let n = match cx.tcx.items.find(did.node) {
         None => return, // This can happen for self, for example
-        Some(ref n) => (*n)
+        Some(ref n) => (/*bad*/copy *n)
     };
     match n {
       ast_map::node_item(item, _) => traverse_public_item(cx, item),
@@ -98,7 +99,7 @@ fn traverse_public_mod(cx: ctx, mod_id: node_id, m: _mod) {
 fn traverse_public_item(cx: ctx, item: @item) {
     if cx.rmap.contains_key(item.id) { return; }
     cx.rmap.insert(item.id, ());
-    match item.node {
+    match /*bad*/copy item.node {
       item_mod(m) => traverse_public_mod(cx, item.id, m),
       item_foreign_mod(nm) => {
           if !traverse_exports(cx, item.id) {
@@ -107,7 +108,7 @@ fn traverse_public_item(cx: ctx, item: @item) {
               }
           }
       }
-      item_fn(_, _, tps, ref blk) => {
+      item_fn(_, _, ref tps, ref blk) => {
         if tps.len() > 0u ||
            attr::find_inline_attr(item.attrs) != attr::ia_none {
             traverse_inline_body(cx, (*blk));
diff --git a/src/librustc/middle/trans/reflect.rs b/src/librustc/middle/trans/reflect.rs
index 792d0ea9a7f..239ed6b83ee 100644
--- a/src/librustc/middle/trans/reflect.rs
+++ b/src/librustc/middle/trans/reflect.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::abi;
 use lib::llvm::{TypeRef, ValueRef};
 use middle::trans::base::*;
@@ -45,16 +46,16 @@ impl reflector {
         C_int(self.bcx.ccx(), i)
     }
 
-    fn c_slice(s: ~str) -> ValueRef {
+    fn c_slice(+s: ~str) -> ValueRef {
         // We're careful to not use first class aggregates here because that
         // will kick us off fast isel. (Issue #4352.)
         let bcx = self.bcx;
         let str_vstore = ty::vstore_slice(ty::re_static);
         let str_ty = ty::mk_estr(bcx.tcx(), str_vstore);
         let scratch = scratch_datum(bcx, str_ty, false);
+        let len = C_uint(bcx.ccx(), s.len() + 1);
         let c_str = PointerCast(bcx, C_cstr(bcx.ccx(), s), T_ptr(T_i8()));
         Store(bcx, c_str, GEPi(bcx, scratch.val, [ 0, 0 ]));
-        let len = C_uint(bcx.ccx(), s.len() + 1);
         Store(bcx, len, GEPi(bcx, scratch.val, [ 0, 1 ]));
         scratch.val
     }
@@ -85,7 +86,9 @@ impl reflector {
             tcx.sess.ident_of(~"visit_" + ty_name),
             *self.visitor_methods).expect(fmt!("Couldn't find visit method \
                                                 for %s", ty_name));
-        let mth_ty = ty::mk_fn(tcx, self.visitor_methods[mth_idx].fty);
+        let mth_ty = ty::mk_fn(
+            tcx,
+            /*bad*/copy self.visitor_methods[mth_idx].fty);
         let v = self.visitor_val;
         debug!("passing %u args:", vec::len(args));
         let bcx = self.bcx;
@@ -110,16 +113,17 @@ impl reflector {
         self.bcx = next_bcx
     }
 
-    fn bracketed(bracket_name: ~str, extra: ~[ValueRef],
+    fn bracketed(bracket_name: ~str, +extra: ~[ValueRef],
                  inner: fn()) {
-        self.visit(~"enter_" + bracket_name, extra);
+        // XXX: Bad copy.
+        self.visit(~"enter_" + bracket_name, copy extra);
         inner();
         self.visit(~"leave_" + bracket_name, extra);
     }
 
     fn vstore_name_and_extra(t: ty::t,
                              vstore: ty::vstore,
-                             f: fn(~str,~[ValueRef])) {
+                             f: fn(+s: ~str,+v: ~[ValueRef])) {
         match vstore {
           ty::vstore_fixed(n) => {
             let extra = vec::append(~[self.c_uint(n)],
@@ -132,7 +136,7 @@ impl reflector {
         }
     }
 
-    fn leaf(name: ~str) {
+    fn leaf(+name: ~str) {
         self.visit(name, ~[]);
     }
 
@@ -143,7 +147,7 @@ impl reflector {
         debug!("reflect::visit_ty %s",
                ty_to_str(bcx.ccx().tcx, t));
 
-        match ty::get(t).sty {
+        match /*bad*/copy ty::get(t).sty {
           ty::ty_bot => self.leaf(~"bot"),
           ty::ty_nil => self.leaf(~"nil"),
           ty::ty_bool => self.leaf(~"bool"),
@@ -219,11 +223,12 @@ impl reflector {
               ast::noreturn => 0u,
               ast::return_val => 1u
             };
+            // XXX: Must we allocate here?
             let extra = ~[self.c_uint(pureval),
                           self.c_uint(protoval),
                           self.c_uint(vec::len(fty.sig.inputs)),
                           self.c_uint(retval)];
-            self.visit(~"enter_fn", extra);
+            self.visit(~"enter_fn", copy extra);    // XXX: Bad copy.
             for fty.sig.inputs.eachi |i, arg| {
                 let modeval = match arg.mode {
                   ast::infer(_) => 0u,
diff --git a/src/librustc/middle/trans/shape.rs b/src/librustc/middle/trans/shape.rs
index c6b8457bb95..9f107997a65 100644
--- a/src/librustc/middle/trans/shape.rs
+++ b/src/librustc/middle/trans/shape.rs
@@ -11,6 +11,7 @@
 // A "shape" is a compact encoding of a type that is used by interpreted glue.
 // This substitutes for the runtime tags used by e.g. MLs.
 
+
 use back::abi;
 use lib::llvm::llvm;
 use lib::llvm::{True, False, ModuleRef, TypeRef, ValueRef};
diff --git a/src/librustc/middle/trans/tvec.rs b/src/librustc/middle/trans/tvec.rs
index b6df2486af2..ee44c80943b 100644
--- a/src/librustc/middle/trans/tvec.rs
+++ b/src/librustc/middle/trans/tvec.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back::abi;
 use lib::llvm::{ValueRef, TypeRef};
 use middle::trans::build::*;
@@ -257,7 +258,7 @@ fn trans_lit_str(bcx: block,
         SaveIn(lldest) => {
             let bytes = lit_str.len() + 1; // count null-terminator too
             let llbytes = C_uint(bcx.ccx(), bytes);
-            let llcstr = C_cstr(bcx.ccx(), *lit_str);
+            let llcstr = C_cstr(bcx.ccx(), /*bad*/copy *lit_str);
             let llcstr = llvm::LLVMConstPointerCast(llcstr, T_ptr(T_i8()));
             Store(bcx, llcstr, GEPi(bcx, lldest, [0u, abi::slice_elt_base]));
             Store(bcx, llbytes, GEPi(bcx, lldest, [0u, abi::slice_elt_len]));
@@ -314,7 +315,7 @@ fn write_content(bcx: block,
            bcx.expr_to_str(vstore_expr));
     let _indenter = indenter();
 
-    match content_expr.node {
+    match /*bad*/copy content_expr.node {
         ast::expr_lit(@{node: ast::lit_str(s), span: _}) => {
             match dest {
                 Ignore => {
@@ -323,7 +324,7 @@ fn write_content(bcx: block,
                 SaveIn(lldest) => {
                     let bytes = s.len() + 1; // copy null-terminator too
                     let llbytes = C_uint(bcx.ccx(), bytes);
-                    let llcstr = C_cstr(bcx.ccx(), *s);
+                    let llcstr = C_cstr(bcx.ccx(), /*bad*/copy *s);
                     base::call_memcpy(bcx, lldest, llcstr, llbytes);
                     return bcx;
                 }
@@ -420,7 +421,7 @@ fn vec_types(bcx: block, vec_ty: ty::t) -> VecTypes {
 fn elements_required(bcx: block, content_expr: @ast::expr) -> uint {
     //! Figure out the number of elements we need to store this content
 
-    match content_expr.node {
+    match /*bad*/copy content_expr.node {
         ast::expr_lit(@{node: ast::lit_str(s), span: _}) => s.len() + 1,
         ast::expr_vec(es, _) => es.len(),
         ast::expr_repeat(_, count_expr, _) => {
diff --git a/src/librustc/middle/trans/type_of.rs b/src/librustc/middle/trans/type_of.rs
index 363807661ae..9f413a65332 100644
--- a/src/librustc/middle/trans/type_of.rs
+++ b/src/librustc/middle/trans/type_of.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use lib::llvm::llvm;
 use lib::llvm::{TypeRef};
 use middle::trans::common::*;
@@ -107,7 +108,8 @@ fn type_of(cx: @crate_ctxt, t: ty::t) -> TypeRef {
         return llty;
     }
 
-    let llty = match ty::get(t).sty {
+    // XXX: This is a terrible terrible copy.
+    let llty = match /*bad*/copy ty::get(t).sty {
       ty::ty_nil | ty::ty_bot => T_nil(),
       ty::ty_bool => T_bool(),
       ty::ty_int(t) => T_int_ty(cx, t),
@@ -122,7 +124,10 @@ fn type_of(cx: @crate_ctxt, t: ty::t) -> TypeRef {
         // avoids creating more than one copy of the enum when one
         // of the enum's variants refers to the enum itself.
 
-        common::T_named_struct(llvm_type_name(cx, an_enum, did, substs.tps))
+        common::T_named_struct(llvm_type_name(cx,
+                                              an_enum,
+                                              did,
+                                              /*bad*/copy substs.tps))
       }
       ty::ty_estr(ty::vstore_box) => {
         T_box_ptr(T_box(cx, T_vec(cx, T_i8())))
@@ -187,7 +192,10 @@ fn type_of(cx: @crate_ctxt, t: ty::t) -> TypeRef {
         // in *after* placing it into the type cache. This prevents
         // infinite recursion with recursive struct types.
 
-        common::T_named_struct(llvm_type_name(cx, a_struct, did, substs.tps))
+        common::T_named_struct(llvm_type_name(cx,
+                                              a_struct,
+                                              did,
+                                              /*bad*/ copy substs.tps))
       }
       ty::ty_self => cx.tcx.sess.unimpl(~"type_of: ty_self"),
       ty::ty_infer(*) => cx.tcx.sess.bug(~"type_of with ty_infer"),
diff --git a/src/librustc/middle/trans/type_use.rs b/src/librustc/middle/trans/type_use.rs
index 6e2e0af86e0..1b2fc4e387a 100644
--- a/src/librustc/middle/trans/type_use.rs
+++ b/src/librustc/middle/trans/type_use.rs
@@ -27,6 +27,7 @@
 // much information, but have the disadvantage of being very
 // invasive.)
 
+
 use metadata::csearch;
 use middle::freevars;
 use middle::trans::common::*;
@@ -84,11 +85,11 @@ fn type_uses_for(ccx: @crate_ctxt, fn_id: def_id, n_tps: uint)
 
     if fn_id_loc.crate != local_crate {
         let uses = vec::from_mut(copy cx.uses);
-        ccx.type_use_cache.insert(fn_id, uses);
+        ccx.type_use_cache.insert(fn_id, copy uses);
         return uses;
     }
     let map_node = match ccx.tcx.items.find(fn_id_loc.node) {
-        Some(ref x) => (*x),
+        Some(ref x) => (/*bad*/copy *x),
         None    => ccx.sess.bug(fmt!("type_uses_for: unbound item ID %?",
                                      fn_id_loc))
     };
@@ -165,7 +166,8 @@ fn type_uses_for(ccx: @crate_ctxt, fn_id: def_id, n_tps: uint)
       }
     }
     let uses = vec::from_mut(copy cx.uses);
-    ccx.type_use_cache.insert(fn_id, uses);
+    // XXX: Bad copy, use @vec instead?
+    ccx.type_use_cache.insert(fn_id, copy uses);
     uses
 }
 
diff --git a/src/librustc/middle/trans/uniq.rs b/src/librustc/middle/trans/uniq.rs
index c4490dd86f3..58853224891 100644
--- a/src/librustc/middle/trans/uniq.rs
+++ b/src/librustc/middle/trans/uniq.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use back;
 use lib::llvm::ValueRef;
 use middle::trans::base::*;
diff --git a/src/librustc/middle/ty.rs b/src/librustc/middle/ty.rs
index 623ba734c91..1841d0b17e3 100644
--- a/src/librustc/middle/ty.rs
+++ b/src/librustc/middle/ty.rs
@@ -1172,9 +1172,9 @@ fn mk_mut_unboxed_vec(cx: ctxt, ty: t) -> t {
     mk_t(cx, ty_unboxed_vec({ty: ty, mutbl: ast::m_imm}))
 }
 
-fn mk_rec(cx: ctxt, fs: ~[field]) -> t { mk_t(cx, ty_rec(fs)) }
+fn mk_rec(cx: ctxt, +fs: ~[field]) -> t { mk_t(cx, ty_rec(fs)) }
 
-fn mk_tup(cx: ctxt, ts: ~[t]) -> t { mk_t(cx, ty_tup(ts)) }
+fn mk_tup(cx: ctxt, +ts: ~[t]) -> t { mk_t(cx, ty_tup(ts)) }
 
 // take a copy because we want to own the various vectors inside
 fn mk_fn(cx: ctxt, +fty: FnTy) -> t { mk_t(cx, ty_fn(fty)) }
@@ -1213,7 +1213,7 @@ fn mk_opaque_closure_ptr(cx: ctxt, proto: ast::Proto) -> t {
 fn mk_opaque_box(cx: ctxt) -> t { mk_t(cx, ty_opaque_box) }
 
 fn mk_with_id(cx: ctxt, base: t, def_id: ast::def_id) -> t {
-    mk_t_with_id(cx, get(base).sty, Some(def_id))
+    mk_t_with_id(cx, /*bad*/copy get(base).sty, Some(def_id))
 }
 
 // Converts s to its machine type equivalent
@@ -1222,7 +1222,7 @@ pure fn mach_sty(cfg: @session::config, t: t) -> sty {
       ty_int(ast::ty_i) => ty_int(cfg.int_type),
       ty_uint(ast::ty_u) => ty_uint(cfg.uint_type),
       ty_float(ast::ty_f) => ty_float(cfg.float_type),
-      ref s => (*s)
+      ref s => (/*bad*/copy *s)
     }
 }
 
@@ -1286,7 +1286,7 @@ fn walk_ty(ty: t, f: fn(t)) {
 
 fn maybe_walk_ty(ty: t, f: fn(t) -> bool) {
     if !f(ty) { return; }
-    match get(ty).sty {
+    match /*bad*/copy get(ty).sty {
       ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
       ty_estr(_) | ty_type | ty_opaque_box | ty_self |
       ty_opaque_closure_ptr(_) | ty_infer(_) | ty_param(_) | ty_err => {
@@ -1322,7 +1322,7 @@ fn fold_sty(sty: &sty, fldop: fn(t) -> t) -> sty {
          tps: substs.tps.map(|t| fldop(*t))}
     }
 
-    match *sty {
+    match /*bad*/copy *sty {
         ty_box(tm) => {
             ty_box({ty: fldop(tm.ty), mutbl: tm.mutbl})
         }
@@ -1376,7 +1376,7 @@ fn fold_sty(sty: &sty, fldop: fn(t) -> t) -> sty {
         ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
         ty_estr(_) | ty_type | ty_opaque_closure_ptr(_) | ty_err |
         ty_opaque_box | ty_infer(_) | ty_param(*) | ty_self => {
-            *sty
+            /*bad*/copy *sty
         }
     }
 }
@@ -1476,7 +1476,7 @@ fn apply_op_on_t_to_ty_fn(
     f: &FnTy,
     t_op: fn(t) -> t) -> FnTy
 {
-    let t0 = ty::mk_fn(cx, *f);
+    let t0 = ty::mk_fn(cx, /*bad*/copy *f);
     let t1 = t_op(t0);
     match ty::get(t1).sty {
         ty::ty_fn(copy f) => {
@@ -1701,7 +1701,7 @@ fn sequence_element_type(cx: ctxt, ty: t) -> t {
 }
 
 fn get_element_type(ty: t, i: uint) -> t {
-    match get(ty).sty {
+    match /*bad*/copy get(ty).sty {
       ty_rec(flds) => return flds[i].mt.ty,
       ty_tup(ts) => return ts[i],
       _ => fail ~"get_element_type called on invalid type"
@@ -1794,7 +1794,7 @@ fn type_needs_drop(cx: ctxt, ty: t) -> bool {
     }
 
     let mut accum = false;
-    let result = match get(ty).sty {
+    let result = match /*bad*/copy get(ty).sty {
       // scalar types
       ty_nil | ty_bot | ty_bool | ty_int(_) | ty_float(_) | ty_uint(_) |
       ty_type | ty_ptr(_) | ty_rptr(_, _) |
@@ -2154,7 +2154,7 @@ fn type_kind_ext(cx: ctxt, ty: t, allow_ty_var: bool) -> Kind {
     // Insert a default in case we loop back on self recursively.
     cx.kind_cache.insert(ty, kind_top());
 
-    let mut result = match get(ty).sty {
+    let mut result = match /*bad*/copy get(ty).sty {
       // Scalar and unique types are sendable, constant, and owned
       ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
       ty_ptr(_) => {
@@ -2326,7 +2326,7 @@ fn type_implicitly_moves(cx: ctxt, ty: t) -> bool {
 /// gives a rough estimate of how much space it takes to represent
 /// an instance of `ty`.  Used for the mode transition.
 fn type_size(cx: ctxt, ty: t) -> uint {
-    match get(ty).sty {
+    match /*bad*/copy get(ty).sty {
       ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
       ty_ptr(_) | ty_box(_) | ty_uniq(_) | ty_estr(vstore_uniq) |
       ty_trait(*) | ty_rptr(*) | ty_evec(_, vstore_uniq) |
@@ -2411,7 +2411,7 @@ fn is_instantiable(cx: ctxt, r_ty: t) -> bool {
                ::util::ppaux::ty_to_str(cx, r_ty),
                ::util::ppaux::ty_to_str(cx, ty));
 
-        let r = match get(ty).sty {
+        let r = match /*bad*/copy get(ty).sty {
           ty_nil |
           ty_bot |
           ty_bool |
@@ -2503,7 +2503,7 @@ fn type_structurally_contains(cx: ctxt, ty: t, test: fn(x: &sty) -> bool) ->
     debug!("type_structurally_contains: %s",
            ::util::ppaux::ty_to_str(cx, ty));
     if test(sty) { return true; }
-    match *sty {
+    match /*bad*/copy *sty {
       ty_enum(did, ref substs) => {
         for vec::each(*enum_variants(cx, did)) |variant| {
             for variant.args.each |aty| {
@@ -2589,7 +2589,7 @@ fn type_is_signed(ty: t) -> bool {
 // that the cycle collector might care about.
 fn type_is_pod(cx: ctxt, ty: t) -> bool {
     let mut result = true;
-    match get(ty).sty {
+    match /*bad*/copy get(ty).sty {
       // Scalar types
       ty_nil | ty_bot | ty_bool | ty_int(_) | ty_float(_) | ty_uint(_) |
       ty_type | ty_ptr(_) => result = true,
@@ -2602,7 +2602,7 @@ fn type_is_pod(cx: ctxt, ty: t) -> bool {
       ty_enum(did, ref substs) => {
         let variants = enum_variants(cx, did);
         for vec::each(*variants) |variant| {
-            let tup_ty = mk_tup(cx, variant.args);
+            let tup_ty = mk_tup(cx, /*bad*/copy variant.args);
 
             // Perform any type parameter substitutions.
             let tup_ty = subst(cx, substs, tup_ty);
@@ -2943,7 +2943,7 @@ fn node_id_has_type_params(cx: ctxt, id: ast::node_id) -> bool {
 // Type accessors for substructures of types
 fn ty_fn_args(fty: t) -> ~[arg] {
     match get(fty).sty {
-      ty_fn(ref f) => f.sig.inputs,
+      ty_fn(ref f) => /*bad*/copy f.sig.inputs,
       _ => fail ~"ty_fn_args() called on non-fn type"
     }
 }
@@ -3054,8 +3054,8 @@ fn method_call_bounds(tcx: ctxt, method_map: typeck::method_map,
             // trait itself.  This ought to be harmonized.
             let trt_bounds =
                 ty::lookup_item_type(tcx, trt_id).bounds;
-            let mth = ty::trait_methods(tcx, trt_id)[n_mth];
-            @(vec::append(*trt_bounds, *mth.tps))
+            let mth = /*bad*/copy ty::trait_methods(tcx, trt_id)[n_mth];
+            @(vec::append(/*bad*/copy *trt_bounds, *mth.tps))
           }
         }
     }
@@ -3252,7 +3252,7 @@ fn get_field(tcx: ctxt, rec_ty: t, id: ast::ident) -> field {
 }
 
 fn get_fields(rec_ty:t) -> ~[field] {
-    match get(rec_ty).sty {
+    match /*bad*/copy get(rec_ty).sty {
       ty_rec(fields) => fields,
       // Can we check at the caller?
       _ => fail ~"get_fields: not a record type"
@@ -3597,7 +3597,7 @@ fn provided_trait_methods(cx: ctxt, id: ast::def_id) -> ~[ast::ident] {
                         node: item_trait(_, _, ref ms),
                         _
                     }, _)) =>
-                match ast_util::split_trait_methods((*ms)) {
+                match ast_util::split_trait_methods((/*bad*/copy *ms)) {
                    (_, p) => p.map(|method| method.ident)
                 },
             _ => cx.sess.bug(fmt!("provided_trait_methods: %? is not a trait",
@@ -3627,7 +3627,7 @@ fn trait_supertraits(cx: ctxt, id: ast::def_id) -> @~[InstantiatedTraitRef] {
             ty_trait(def_id, ref substs, _) => {
                 result.push(InstantiatedTraitRef {
                     def_id: def_id,
-                    tpt: { substs: (*substs), ty: *trait_type }
+                    tpt: { substs: (/*bad*/copy *substs), ty: *trait_type }
                 });
             }
             _ => cx.sess.bug(~"trait_supertraits: trait ref wasn't a trait")
@@ -3665,7 +3665,7 @@ fn impl_traits(cx: ctxt, id: ast::def_id, vstore: vstore) -> ~[t] {
         match ty::get(ty).sty {
             ty::ty_trait(_, _, trait_vstore) if vstore == trait_vstore => ty,
             ty::ty_trait(did, ref substs, _) => {
-                mk_trait(cx, did, (*substs), vstore)
+                mk_trait(cx, did, (/*bad*/copy *substs), vstore)
             }
             _ => cx.sess.bug(~"impl_traits: not a trait")
         }
@@ -3745,7 +3745,7 @@ fn substd_enum_variants(cx: ctxt,
         let substd_ctor_ty = subst(cx, substs, variant_info.ctor_ty);
 
         @VariantInfo_{args: substd_args, ctor_ty: substd_ctor_ty,
-                      ..**variant_info}
+                      ../*bad*/copy **variant_info}
     }
 }
 
@@ -3817,19 +3817,22 @@ fn item_path(cx: ctxt, id: ast::def_id) -> ast_map::path {
                 ast_map::path_name(item.ident)
               }
             };
-            vec::append_one(*path, item_elt)
+            vec::append_one(/*bad*/copy *path, item_elt)
           }
 
           ast_map::node_foreign_item(nitem, _, path) => {
-            vec::append_one(*path, ast_map::path_name(nitem.ident))
+            vec::append_one(/*bad*/copy *path,
+                            ast_map::path_name(nitem.ident))
           }
 
           ast_map::node_method(method, _, path) => {
-            vec::append_one(*path, ast_map::path_name(method.ident))
+            vec::append_one(/*bad*/copy *path,
+                            ast_map::path_name(method.ident))
           }
           ast_map::node_trait_method(trait_method, _, path) => {
             let method = ast_util::trait_method_to_ty_method(*trait_method);
-            vec::append_one(*path, ast_map::path_name(method.ident))
+            vec::append_one(/*bad*/copy *path,
+                            ast_map::path_name(method.ident))
           }
 
           ast_map::node_variant(ref variant, _, path) => {
@@ -3838,12 +3841,12 @@ fn item_path(cx: ctxt, id: ast::def_id) -> ast_map::path {
           }
 
           ast_map::node_dtor(_, _, _, path) => {
-            vec::append_one(*path, ast_map::path_name(
+            vec::append_one(/*bad*/copy *path, ast_map::path_name(
                 syntax::parse::token::special_idents::literally_dtor))
           }
 
           ast_map::node_struct_ctor(_, item, path) => {
-            vec::append_one(*path, ast_map::path_name(item.ident))
+            vec::append_one(/*bad*/copy *path, ast_map::path_name(item.ident))
           }
 
           ast_map::node_stmt(*) | ast_map::node_expr(*) |
@@ -3885,7 +3888,7 @@ fn enum_variants(cx: ctxt, id: ast::def_id) -> @~[VariantInfo] {
                     node: ast::item_enum(ref enum_definition, _),
                     _
                 }, _) => {
-            let variants = (*enum_definition).variants;
+            let variants = /*bad*/copy (*enum_definition).variants;
             let mut disr_val = -1;
             @vec::map(variants, |variant| {
                 match variant.node.kind {
@@ -3994,7 +3997,7 @@ fn lookup_struct_fields(cx: ctxt, did: ast::def_id) -> ~[field_ty] {
        Some(ast_map::node_item(i,_)) => {
          match i.node {
             ast::item_struct(struct_def, _) => {
-               struct_field_tys(struct_def.fields)
+               struct_field_tys(/*bad*/copy struct_def.fields)
             }
             _ => cx.sess.bug(~"struct ID bound to non-struct")
          }
@@ -4002,7 +4005,7 @@ fn lookup_struct_fields(cx: ctxt, did: ast::def_id) -> ~[field_ty] {
        Some(ast_map::node_variant(ref variant, _, _)) => {
           match (*variant).node.kind {
             ast::struct_variant_kind(struct_def) => {
-              struct_field_tys(struct_def.fields)
+              struct_field_tys(/*bad*/copy struct_def.fields)
             }
             _ => {
               cx.sess.bug(~"struct ID bound to enum variant that isn't \
@@ -4211,7 +4214,7 @@ fn normalize_ty(cx: ctxt, t: t) -> t {
                     region: ty::re_static,
                     ..fn_ty.meta
                 },
-                sig: fn_ty.sig
+                sig: /*bad*/copy fn_ty.sig
             })
         }
 
@@ -4222,7 +4225,7 @@ fn normalize_ty(cx: ctxt, t: t) -> t {
                     mk_enum(cx, did,
                      {self_r: Some(ty::re_static),
                       self_ty: None,
-                      tps: (*r).tps}),
+                      tps: /*bad*/copy (*r).tps}),
                 None =>
                     t
             },
@@ -4233,7 +4236,7 @@ fn normalize_ty(cx: ctxt, t: t) -> t {
                 // Ditto.
                 mk_struct(cx, did, {self_r: Some(ty::re_static),
                                     self_ty: None,
-                                    tps: (*r).tps}),
+                                    tps: /*bad*/copy (*r).tps}),
               None =>
                 t
             },
@@ -4537,7 +4540,7 @@ impl InferTy : cmp::Eq {
 
 impl sty : cmp::Eq {
     pure fn eq(&self, other: &sty) -> bool {
-        match (*self) {
+        match (/*bad*/copy *self) {
             ty_nil => {
                 match (*other) {
                     ty_nil => true,
@@ -4617,7 +4620,7 @@ impl sty : cmp::Eq {
                 }
             }
             ty_rec(e0a) => {
-                match (*other) {
+                match (/*bad*/copy *other) {
                     ty_rec(e0b) => e0a == e0b,
                     _ => false
                 }
@@ -4642,7 +4645,7 @@ impl sty : cmp::Eq {
                 }
             }
             ty_tup(e0a) => {
-                match (*other) {
+                match (/*bad*/copy *other) {
                     ty_tup(e0b) => e0a == e0b,
                     _ => false
                 }
diff --git a/src/librustc/middle/typeck/astconv.rs b/src/librustc/middle/typeck/astconv.rs
index 82438f86e9f..635a83ba251 100644
--- a/src/librustc/middle/typeck/astconv.rs
+++ b/src/librustc/middle/typeck/astconv.rs
@@ -52,6 +52,7 @@
  * an rptr (`&r.T`) use the region `r` that appears in the rptr.
  */
 
+
 use middle::ty::{FnTyBase, FnMeta, FnSig};
 use middle::ty;
 use middle::typeck::check::fn_ctxt;
@@ -80,7 +81,7 @@ fn get_region_reporting_err(tcx: ty::ctxt,
     match res {
       result::Ok(r) => r,
       result::Err(ref e) => {
-        tcx.sess.span_err(span, (*e));
+        tcx.sess.span_err(span, (/*bad*/copy *e));
         ty::re_static
       }
     }
@@ -145,7 +146,8 @@ fn ast_path_to_substs_and_ty<AC: ast_conv, RS: region_scope Copy Durable>(
     let tps = path.types.map(|a_t| ast_ty_to_ty(self, rscope, *a_t));
 
     let substs = {self_r:self_r, self_ty:None, tps:tps};
-    {substs: substs, ty: ty::subst(tcx, &substs, decl_ty)}
+    let ty = ty::subst(tcx, &substs, decl_ty);
+    {substs: substs, ty: ty}
 }
 
 pub fn ast_path_to_ty<AC: ast_conv, RS: region_scope Copy Durable>(
@@ -161,7 +163,7 @@ pub fn ast_path_to_ty<AC: ast_conv, RS: region_scope Copy Durable>(
     let {substs: substs, ty: ty} =
         ast_path_to_substs_and_ty(self, rscope, did, path);
     write_ty_to_tcx(tcx, path_id, ty);
-    write_substs_to_tcx(tcx, path_id, substs.tps);
+    write_substs_to_tcx(tcx, path_id, /*bad*/copy substs.tps);
     return {substs: substs, ty: ty};
 }
 
@@ -225,7 +227,7 @@ fn ast_ty_to_ty<AC: ast_conv, RS: region_scope Copy Durable>(
                                     }
                                 }
                                 return ty::mk_trait(tcx, trait_def_id,
-                                                    (*substs), vst);
+                                                    /*bad*/copy *substs, vst);
 
                             }
                             _ => {}
@@ -274,7 +276,7 @@ fn ast_ty_to_ty<AC: ast_conv, RS: region_scope Copy Durable>(
     }
 
     tcx.ast_ty_to_ty_cache.insert(ast_ty, ty::atttce_unresolved);
-    let typ = match ast_ty.node {
+    let typ = match /*bad*/copy ast_ty.node {
       ast::ty_nil => ty::mk_nil(tcx),
       ast::ty_bot => ty::mk_bot(tcx),
       ast::ty_box(mt) => {
diff --git a/src/librustc/middle/typeck/check/alt.rs b/src/librustc/middle/typeck/check/alt.rs
index 2c3bf1eeb18..95bd9a39769 100644
--- a/src/librustc/middle/typeck/check/alt.rs
+++ b/src/librustc/middle/typeck/check/alt.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::pat_util::{pat_is_binding, pat_is_const};
 use middle::pat_util::{pat_is_variant_or_struct};
 use middle::ty;
@@ -69,7 +70,7 @@ struct pat_ctxt {
 }
 
 fn check_pat_variant(pcx: pat_ctxt, pat: @ast::pat, path: @ast::path,
-                     subpats: Option<~[@ast::pat]>, expected: ty::t) {
+                     +subpats: Option<~[@ast::pat]>, expected: ty::t) {
 
     // Typecheck the path.
     let fcx = pcx.fcx;
@@ -150,7 +151,7 @@ fn check_pat_variant(pcx: pat_ctxt, pat: @ast::pat, path: @ast::path,
     let subpats_len;
     match subpats {
         None => subpats_len = arg_len,
-        Some(subpats) => subpats_len = subpats.len()
+        Some(ref subpats) => subpats_len = subpats.len()
     }
 
     if arg_len > 0u {
@@ -244,7 +245,7 @@ fn check_struct_pat_fields(pcx: pat_ctxt,
 
 fn check_struct_pat(pcx: pat_ctxt, pat_id: ast::node_id, span: span,
                     expected: ty::t, path: @ast::path,
-                    fields: ~[ast::field_pat], etc: bool,
+                    +fields: ~[ast::field_pat], etc: bool,
                     class_id: ast::def_id, substitutions: &ty::substs) {
     let fcx = pcx.fcx;
     let tcx = pcx.fcx.ccx.tcx;
@@ -285,7 +286,7 @@ fn check_struct_like_enum_variant_pat(pcx: pat_ctxt,
                                       span: span,
                                       expected: ty::t,
                                       path: @ast::path,
-                                      fields: ~[ast::field_pat],
+                                      +fields: ~[ast::field_pat],
                                       etc: bool,
                                       enum_id: ast::def_id,
                                       substitutions: &ty::substs) {
@@ -322,7 +323,7 @@ fn check_pat(pcx: pat_ctxt, pat: @ast::pat, expected: ty::t) {
     let fcx = pcx.fcx;
     let tcx = pcx.fcx.ccx.tcx;
 
-    match pat.node {
+    match /*bad*/copy pat.node {
       ast::pat_wild => {
         fcx.write_ty(pat.id, expected);
       }
diff --git a/src/librustc/middle/typeck/check/demand.rs b/src/librustc/middle/typeck/check/demand.rs
index 1f8c9c84550..954608540f5 100644
--- a/src/librustc/middle/typeck/check/demand.rs
+++ b/src/librustc/middle/typeck/check/demand.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::typeck::check::fn_ctxt;
 use middle::typeck::infer;
diff --git a/src/librustc/middle/typeck/check/method.rs b/src/librustc/middle/typeck/check/method.rs
index a3df14be9c6..1a788fd9574 100644
--- a/src/librustc/middle/typeck/check/method.rs
+++ b/src/librustc/middle/typeck/check/method.rs
@@ -79,6 +79,7 @@ obtained the type `Foo`, we would never match this method.
 
 */
 
+
 use middle::resolve::{Impl, MethodInfo};
 use middle::resolve;
 use middle::ty::*;
@@ -358,7 +359,7 @@ impl LookupContext {
 
 
             let bound_substs = match ty::get(bound_trait_ty).sty {
-                ty::ty_trait(_, ref substs, _) => (*substs),
+                ty::ty_trait(_, ref substs, _) => (/*bad*/copy *substs),
                 _ => {
                     self.bug(fmt!("add_candidates_from_param: \
                                    non-trait bound %s",
@@ -386,7 +387,7 @@ impl LookupContext {
 
             let mut i = 0;
             while i < worklist.len() {
-                let (init_trait_ty, init_substs) = worklist[i];
+                let (init_trait_ty, init_substs) = /*bad*/copy worklist[i];
                 i += 1;
 
                 let init_trait_id = ty::ty_to_def_id(init_trait_ty).get();
@@ -491,7 +492,7 @@ impl LookupContext {
         // `trait_ty` for `self` here, because it allows the compiler
         // to soldier on.  An error will be reported should this
         // candidate be selected if the method refers to `self`.
-        let rcvr_substs = {self_ty: Some(self_ty), ..*substs};
+        let rcvr_substs = {self_ty: Some(self_ty), ../*bad*/copy *substs};
 
         let (rcvr_ty, rcvr_substs) =
             self.create_rcvr_ty_and_substs_for_method(method.self_ty,
@@ -522,7 +523,7 @@ impl LookupContext {
         }
         let method = &methods[index];
 
-        let rcvr_substs = { self_ty: Some(self_ty), ..*substs };
+        let rcvr_substs = { self_ty: Some(self_ty), ../*bad*/copy *substs };
         let (rcvr_ty, rcvr_substs) =
             self.create_rcvr_ty_and_substs_for_method(
                 method.self_ty,
@@ -893,13 +894,13 @@ impl LookupContext {
         let mut merged = ~[];
         let mut i = 0;
         while i < candidates.len() {
-            let candidate_a = candidates[i];
+            let candidate_a = /*bad*/copy candidates[i];
 
             let mut skip = false;
 
             let mut j = i + 1;
             while j < candidates.len() {
-                let candidate_b = candidates[j];
+                let candidate_b = /*bad*/copy candidates[j];
                 debug!("attempting to merge %? and %?",
                        candidate_a, candidate_b);
                 let candidates_same = match (&candidate_a.origin,
@@ -985,9 +986,11 @@ impl LookupContext {
 
         // Construct the full set of type parameters for the method,
         // which is equal to the class tps + the method tps.
-        let all_substs = {tps: vec::append(candidate.rcvr_substs.tps,
-                                           m_substs),
-                          ..candidate.rcvr_substs};
+        let all_substs = {
+            tps: vec::append(/*bad*/copy candidate.rcvr_substs.tps,
+                             m_substs),
+            ../*bad*/copy candidate.rcvr_substs
+        };
 
         self.fcx.write_ty_substs(self.callee_id, fty, all_substs);
         return {self_arg: {mode: ast::expl(candidate.self_mode),
@@ -1072,7 +1075,7 @@ impl LookupContext {
                                 trait_did: def_id,
                                 method_num: uint) -> ty::t {
             let trait_methods = ty::trait_methods(tcx, trait_did);
-            ty::mk_fn(tcx, trait_methods[method_num].fty)
+            ty::mk_fn(tcx, /*bad*/copy trait_methods[method_num].fty)
         }
     }
 
@@ -1147,7 +1150,7 @@ impl LookupContext {
         ty::item_path_str(self.tcx(), did)
     }
 
-    fn bug(&self, s: ~str) -> ! {
+    fn bug(&self, +s: ~str) -> ! {
         self.tcx().sess.bug(s)
     }
 }
diff --git a/src/librustc/middle/typeck/check/mod.rs b/src/librustc/middle/typeck/check/mod.rs
index 73d8ed99159..3086b2e7227 100644
--- a/src/librustc/middle/typeck/check/mod.rs
+++ b/src/librustc/middle/typeck/check/mod.rs
@@ -76,6 +76,7 @@ type parameter).
 
 */
 
+
 use middle::capture;
 use middle::const_eval;
 use middle::pat_util;
@@ -349,7 +350,8 @@ fn check_fn(ccx: @crate_ctxt,
         }
     };
 
-    gather_locals(fcx, decl, body, arg_tys, self_info);
+    // XXX: Bad copy.
+    gather_locals(fcx, decl, body, copy arg_tys, self_info);
     check_block(fcx, body);
 
     // We unify the tail expr's type with the
@@ -546,13 +548,16 @@ fn check_item(ccx: @crate_ctxt, it: @ast::item) {
            ty::item_path_str(ccx.tcx, local_def(it.id)));
     let _indenter = indenter();
 
-    match it.node {
+    match /*bad*/copy it.node {
       ast::item_const(_, e) => check_const(ccx, it.span, e, it.id),
       ast::item_enum(ref enum_definition, _) => {
-        check_enum_variants(ccx, it.span, (*enum_definition).variants, it.id);
+        check_enum_variants(ccx,
+                            it.span,
+                            /*bad*/copy (*enum_definition).variants,
+                            it.id);
       }
-      ast::item_fn(decl, _, _, ref body) => {
-        check_bare_fn(ccx, decl, (*body), it.id, None);
+      ast::item_fn(ref decl, _, _, ref body) => {
+        check_bare_fn(ccx, *decl, (*body), it.id, None);
       }
       ast::item_impl(_, _, ty, ms) => {
         let rp = ccx.tcx.region_paramd_items.find(it.id);
@@ -743,7 +748,7 @@ impl @fn_ctxt {
     }
     fn node_ty_substs(id: ast::node_id) -> ty::substs {
         match self.inh.node_type_substs.find(id) {
-            Some(ref ts) => (*ts),
+            Some(ref ts) => (/*bad*/copy *ts),
             None => {
                 self.tcx().sess.bug(
                     fmt!("no type substs for node %d: %s in fcx %s",
@@ -973,13 +978,13 @@ pub fn impl_self_ty(vcx: &VtableContext,
     let {n_tps, region_param, raw_ty} = if did.crate == ast::local_crate {
         let region_param = tcx.region_paramd_items.find(did.node);
         match tcx.items.find(did.node) {
-          Some(ast_map::node_item(@{node: ast::item_impl(ts, _, st, _),
+          Some(ast_map::node_item(@{node: ast::item_impl(ref ts, _, st, _),
                                   _}, _)) => {
             {n_tps: ts.len(),
              region_param: region_param,
              raw_ty: vcx.ccx.to_ty(rscope::type_rscope(region_param), st)}
           }
-          Some(ast_map::node_item(@{node: ast::item_struct(_, ts),
+          Some(ast_map::node_item(@{node: ast::item_struct(_, ref ts),
                                     id: class_id, _},_)) => {
               /* If the impl is a class, the self ty is just the class ty
                  (doing a no-op subst for the ty params; in the next step,
@@ -990,7 +995,7 @@ pub fn impl_self_ty(vcx: &VtableContext,
                raw_ty: ty::mk_struct(tcx, local_def(class_id),
                       {self_r: rscope::bound_self_region(region_param),
                        self_ty: None,
-                       tps: ty::ty_params_to_tys(tcx, ts)})}
+                       tps: ty::ty_params_to_tys(tcx, /*bad*/copy *ts)})}
           }
           _ => { tcx.sess.bug(~"impl_self_ty: unbound item or item that \
                doesn't have a self_ty"); }
@@ -1036,6 +1041,10 @@ pub enum DerefArgs {
     DoDerefArgs
 }
 
+fn break_here() {
+    debug!("break here!");
+}
+
 fn check_expr_with_unifier(fcx: @fn_ctxt,
                            expr: @ast::expr,
                            expected: Option<ty::t>,
@@ -1072,7 +1081,8 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
         let fty =
             match structure_of(fcx, sp, in_fty) {
               ty::ty_fn(ref fn_ty) => {
-                  let fn_ty = replace_bound_regions_in_fn_ty(tcx, @Nil,
+                  let fn_ty =
+                    /*bad*/copy replace_bound_regions_in_fn_ty(tcx, @Nil,
                       None, fn_ty, |_br| fcx.infcx().next_region_var(sp,
                                                       call_expr_id)).fn_ty;
 
@@ -1189,7 +1199,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                             call_expr_id: ast::node_id,
                             fn_ty: ty::t,
                             expr: @ast::expr,
-                            args: ~[@ast::expr],
+                            +args: ~[@ast::expr],
                             bot: bool)
                          -> bool {
         let mut bot = bot;
@@ -1220,11 +1230,10 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
 
     // A generic function for doing all of the checking for call expressions
     fn check_call(fcx: @fn_ctxt, sp: span, call_expr_id: ast::node_id,
-                  f: @ast::expr, args: ~[@ast::expr]) -> bool {
-
+                  f: @ast::expr, +args: ~[@ast::expr]) -> bool {
         // Index expressions need to be handled separately, to inform them
         // that they appear in call position.
-        let mut bot = match f.node {
+        let mut bot = match /*bad*/copy f.node {
             ast::expr_field(base, field, tys) => {
                 check_field(fcx, f, true, base, field, tys)
             }
@@ -1245,7 +1254,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                          expr: @ast::expr,
                          rcvr: @ast::expr,
                          method_name: ast::ident,
-                         args: ~[@ast::expr],
+                         +args: ~[@ast::expr],
                          tps: ~[@ast::Ty])
                       -> bool {
         let bot = check_expr(fcx, rcvr, None);
@@ -1331,7 +1340,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
 
     fn lookup_op_method(fcx: @fn_ctxt, op_ex: @ast::expr,
                         self_ex: @ast::expr, self_t: ty::t,
-                        opname: ast::ident, args: ~[@ast::expr],
+                        opname: ast::ident, +args: ~[@ast::expr],
                         +deref_args: DerefArgs)
         -> Option<(ty::t, bool)>
     {
@@ -1509,7 +1518,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                         replace_bound_regions_in_fn_ty(
                             tcx, @Nil, None, fn_ty,
                             |br| ty::re_bound(ty::br_cap_avoid(id, @br)));
-                    (Some({inputs: fn_ty.sig.inputs,
+                    (Some({inputs: /*bad*/copy fn_ty.sig.inputs,
                            output: fn_ty.sig.output}),
                      fn_ty.meta.purity,
                      fn_ty.meta.proto,
@@ -1535,7 +1544,8 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
             /*bounds:*/ @~[], /*opt_region:*/ None,
             decl, expected_tys, expr.span);
 
-        let fty = ty::mk_fn(tcx, fn_ty);
+        // XXX: Bad copy.
+        let fty = ty::mk_fn(tcx, copy fn_ty);
 
         debug!("check_expr_fn_with_unifier %s fty=%s",
                expr_to_str(expr, tcx.sess.intr()),
@@ -1724,7 +1734,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                 tcx.region_paramd_items.find(class_id.node);
             match tcx.items.find(class_id.node) {
                 Some(ast_map::node_item(@{
-                        node: ast::item_struct(_, type_parameters),
+                        node: ast::item_struct(_, ref type_parameters),
                         _
                     }, _)) => {
 
@@ -1736,7 +1746,9 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                     raw_type = ty::mk_struct(tcx, class_id, {
                         self_r: self_region,
                         self_ty: None,
-                        tps: ty::ty_params_to_tys(tcx, type_parameters)
+                        tps: ty::ty_params_to_tys(
+                            tcx,
+                            /*bad*/copy *type_parameters)
                     });
                 }
                 _ => {
@@ -1805,7 +1817,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                 tcx.region_paramd_items.find(enum_id.node);
             match tcx.items.find(enum_id.node) {
                 Some(ast_map::node_item(@{
-                        node: ast::item_enum(_, type_parameters),
+                        node: ast::item_enum(_, ref type_parameters),
                         _
                     }, _)) => {
 
@@ -1817,7 +1829,9 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                     raw_type = ty::mk_enum(tcx, enum_id, {
                         self_r: self_region,
                         self_ty: None,
-                        tps: ty::ty_params_to_tys(tcx, type_parameters)
+                        tps: ty::ty_params_to_tys(
+                            tcx,
+                            /*bad*/copy *type_parameters)
                     });
                 }
                 _ => {
@@ -1864,9 +1878,9 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
     let tcx = fcx.ccx.tcx;
     let id = expr.id;
     let mut bot = false;
-    match expr.node {
+    match /*bad*/copy expr.node {
       ast::expr_vstore(ev, vst) => {
-        let typ = match ev.node {
+        let typ = match /*bad*/copy ev.node {
           ast::expr_lit(@{node: ast::lit_str(s), span:_}) => {
             let tt = ast_expr_vstore_to_vstore(fcx, ev, str::len(*s), vst);
             ty::mk_estr(tcx, tt)
@@ -2108,16 +2122,16 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
         bot = !may_break(tcx, expr.id, (*body));
       }
       ast::expr_match(discrim, ref arms) => {
-        bot = alt::check_alt(fcx, expr, discrim, (*arms));
+        bot = alt::check_alt(fcx, expr, discrim, (/*bad*/copy *arms));
       }
-      ast::expr_fn(proto, decl, ref body, cap_clause) => {
+      ast::expr_fn(proto, ref decl, ref body, cap_clause) => {
         check_expr_fn(fcx, expr, Some(proto),
-                      decl, (*body), Vanilla, expected);
+                      *decl, (*body), Vanilla, expected);
         capture::check_capture_clause(tcx, expr.id, cap_clause);
       }
-      ast::expr_fn_block(decl, ref body, cap_clause) => {
+      ast::expr_fn_block(ref decl, ref body, cap_clause) => {
         check_expr_fn(fcx, expr, None,
-                      decl, (*body), Vanilla, expected);
+                      *decl, (*body), Vanilla, expected);
         capture::check_capture_clause(tcx, expr.id, cap_clause);
       }
       ast::expr_loop_body(b) => {
@@ -2148,7 +2162,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
             ty::mk_fn(tcx, FnTyBase {
                 meta: (*fty).meta,
                 sig: FnSig {output: ty::mk_nil(tcx),
-                            ..(*fty).sig}
+                            ../*bad*/copy (*fty).sig}
             })
           }
           _ =>
@@ -2171,9 +2185,9 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
               }
         };
         match b.node {
-          ast::expr_fn_block(decl, ref body, cap_clause) => {
+          ast::expr_fn_block(ref decl, ref body, cap_clause) => {
             check_expr_fn(fcx, b, None,
-                          decl, (*body), ForLoop, Some(inner_ty));
+                          *decl, (*body), ForLoop, Some(inner_ty));
             demand::suptype(fcx, b.span, inner_ty, fcx.expr_ty(b));
             capture::check_capture_clause(tcx, b.id, cap_clause);
           }
@@ -2188,7 +2202,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
                   fcx.write_ty(expr.id, ty::mk_fn(tcx, FnTyBase {
                       meta: (*fty).meta,
                       sig: FnSig {output: ty::mk_bool(tcx),
-                                  ..(*fty).sig}
+                                  ../*bad*/copy (*fty).sig}
                   }));
               }
               else {
@@ -2202,7 +2216,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
         let expected_sty = unpack_expected(fcx, expected, |x| Some(x));
         let inner_ty = match expected_sty {
           Some(ty::ty_fn(ref fty)) => {
-              ty::mk_fn(tcx, (*fty))
+              ty::mk_fn(tcx, (/*bad*/copy *fty))
           }
           _ => match expected {
                   Some(expected_t) => {
@@ -2220,9 +2234,9 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
               }
         };
         match b.node {
-          ast::expr_fn_block(decl, ref body, cap_clause) => {
+          ast::expr_fn_block(ref decl, ref body, cap_clause) => {
             check_expr_fn(fcx, b, None,
-                          decl, (*body), DoBlock, Some(inner_ty));
+                          *decl, (*body), DoBlock, Some(inner_ty));
             demand::suptype(fcx, b.span, inner_ty, fcx.expr_ty(b));
             capture::check_capture_clause(tcx, b.id, cap_clause);
           }
@@ -2233,7 +2247,7 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
             fcx, expr.span, fcx.node_ty(b.id));
         match ty::get(block_ty).sty {
           ty::ty_fn(ref fty) => {
-            fcx.write_ty(expr.id, ty::mk_fn(tcx, (*fty)));
+            fcx.write_ty(expr.id, ty::mk_fn(tcx, (/*bad*/copy *fty)));
           }
           _ => fail ~"expected fn ty"
         }
@@ -2315,7 +2329,11 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
       }
       ast::expr_tup(elts) => {
         let flds = unpack_expected(fcx, expected, |sty| {
-            match sty { ty::ty_tup(flds) => Some(flds), _ => None }
+            // XXX: Beware! If you remove `copy` below, the borrow checker
+            // will NOT complain, but you will get a segfault at runtime! This
+            // is because the mode computation is currently unaware of
+            // argument modes.
+            match copy sty { ty::ty_tup(flds) => Some(flds), _ => None }
         });
         let elt_ts = do elts.mapi |i, e| {
             check_expr(fcx, *e, flds.map(|fs| fs[i]));
@@ -2330,7 +2348,14 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
             Some(fcx.expr_ty(base.get()))
         } else { expected };
         let flds = unpack_expected(fcx, expected, |sty|
-            match sty { ty::ty_rec(flds) => Some(flds), _ => None }
+            // XXX: Beware! If you remove `copy` below, the borrow checker
+            // will NOT complain, but you will get a segfault at runtime! This
+            // is because the mode computation is currently unaware of
+            // argument modes.
+            match copy sty {
+                ty::ty_rec(flds) => Some(flds),
+                _ => None
+            }
         );
         let fields_t = vec::map((*fields), |f| {
             bot |= check_expr(fcx, f.node.expr, flds.chain_ref(|flds|
@@ -2392,11 +2417,11 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
         match tcx.def_map.find(id) {
             Some(ast::def_struct(type_def_id)) => {
                 check_struct_constructor(fcx, id, expr.span, type_def_id,
-                                         (*fields), base_expr);
+                                         (/*bad*/copy *fields), base_expr);
             }
             Some(ast::def_variant(enum_id, variant_id)) => {
                 check_struct_enum_variant(fcx, id, expr.span, enum_id,
-                                          variant_id, (*fields));
+                                          variant_id, (/*bad*/copy *fields));
             }
             _ => {
                 tcx.sess.span_bug(path.span, ~"structure constructor does \
@@ -2441,8 +2466,9 @@ fn check_expr_with_unifier(fcx: @fn_ctxt,
     }
     if bot { fcx.write_bot(expr.id); }
 
-    debug!("type of expr %s is %s, expected is %s",
-           syntax::print::pprust::expr_to_str(expr, tcx.sess.intr()),
+    debug!("type of expr %s is...",
+           syntax::print::pprust::expr_to_str(expr, tcx.sess.intr()));
+    debug!("... %s, expected is %s",
            ppaux::ty_to_str(tcx, fcx.expr_ty(expr)),
            match expected {
                Some(t) => ppaux::ty_to_str(tcx, t),
@@ -2502,7 +2528,7 @@ fn check_stmt(fcx: @fn_ctxt, stmt: @ast::stmt) -> bool {
     match stmt.node {
       ast::stmt_decl(decl, id) => {
         node_id = id;
-        match decl.node {
+        match /*bad*/copy decl.node {
           ast::decl_local(ls) => for ls.each |l| {
             bot |= check_decl_local(fcx, *l);
           },
@@ -2614,7 +2640,7 @@ fn check_instantiable(tcx: ty::ctxt,
 
 fn check_enum_variants(ccx: @crate_ctxt,
                        sp: span,
-                       vs: ~[ast::variant],
+                       +vs: ~[ast::variant],
                        id: ast::node_id) {
     fn do_check(ccx: @crate_ctxt, sp: span, vs: ~[ast::variant],
                 id: ast::node_id, disr_vals: &mut ~[int], disr_val: &mut int,
@@ -2659,7 +2685,7 @@ fn check_enum_variants(ccx: @crate_ctxt,
             *disr_val += 1;
 
             match v.node.kind {
-                ast::tuple_variant_kind(args) if args.len() > 0u => {
+                ast::tuple_variant_kind(ref args) if args.len() > 0u => {
                     arg_tys = Some(ty::ty_fn_args(ctor_ty).map(|a| a.ty));
                 }
                 ast::tuple_variant_kind(_) => {
@@ -2672,7 +2698,13 @@ fn check_enum_variants(ccx: @crate_ctxt,
                 }
                 ast::enum_variant_kind(_) => {
                     arg_tys = None;
-                    do_check(ccx, sp, vs, id, disr_vals, disr_val, variants);
+                    do_check(ccx,
+                             sp,
+                             /*bad*/copy vs,
+                             id,
+                             disr_vals,
+                             disr_val,
+                             variants);
                 }
             }
 
@@ -2809,6 +2841,8 @@ fn instantiate_path(fcx: @fn_ctxt,
                     span: span,
                     node_id: ast::node_id,
                     region_lb: ty::Region) {
+    debug!(">>> instantiate_path");
+
     let ty_param_count = vec::len(*tpt.bounds);
     let ty_substs_len = vec::len(pth.types);
 
@@ -2855,6 +2889,8 @@ fn instantiate_path(fcx: @fn_ctxt,
 
     let substs = {self_r: self_r, self_ty: None, tps: tps};
     fcx.write_ty_substs(node_id, tpt.ty, substs);
+
+    debug!("<<<");
 }
 
 // Resolves `typ` by a single level if `typ` is a type variable.  If no
@@ -2873,7 +2909,7 @@ fn structurally_resolved_type(fcx: @fn_ctxt, sp: span, tp: ty::t) -> ty::t {
 
 // Returns the one-level-deep structure of the given type.
 fn structure_of(fcx: @fn_ctxt, sp: span, typ: ty::t) -> ty::sty {
-    ty::get(structurally_resolved_type(fcx, sp, typ)).sty
+    /*bad*/copy ty::get(structurally_resolved_type(fcx, sp, typ)).sty
 }
 
 fn type_is_integral(fcx: @fn_ctxt, sp: span, typ: ty::t) -> bool {
diff --git a/src/librustc/middle/typeck/check/regionck.rs b/src/librustc/middle/typeck/check/regionck.rs
index 797a21c38e2..c74b5789075 100644
--- a/src/librustc/middle/typeck/check/regionck.rs
+++ b/src/librustc/middle/typeck/check/regionck.rs
@@ -27,6 +27,7 @@ this point a bit better.
 
 */
 
+
 use middle::freevars::get_freevars;
 use middle::pat_util::pat_bindings;
 use middle::ty::{encl_region, re_scope};
@@ -168,7 +169,7 @@ fn visit_expr(expr: @ast::expr, &&rcx: @rcx, v: rvt) {
     debug!("visit_expr(e=%s)",
            pprust::expr_to_str(expr, rcx.fcx.tcx().sess.intr()));
 
-    match expr.node {
+    match /*bad*/copy expr.node {
         ast::expr_path(*) => {
             // Avoid checking the use of local variables, as we
             // already check their definitions.  The def'n always
diff --git a/src/librustc/middle/typeck/check/regionmanip.rs b/src/librustc/middle/typeck/check/regionmanip.rs
index dfba93f947f..c7000bb7e70 100644
--- a/src/librustc/middle/typeck/check/regionmanip.rs
+++ b/src/librustc/middle/typeck/check/regionmanip.rs
@@ -9,7 +9,6 @@
 // except according to those terms.
 
 // #[warn(deprecated_mode)];
-// #[warn(deprecated_pattern)];
 
 use middle::ty;
 use util::ppaux;
@@ -60,7 +59,7 @@ fn replace_bound_regions_in_fn_ty(
         debug!("br=%?", br);
         mapf(br)
     };
-    let ty_fn = ty::ty_fn(*fn_ty);
+    let ty_fn = ty::ty_fn(/*bad*/copy *fn_ty);
     let t_fn = ty::fold_sty_to_ty(tcx, &ty_fn, |t| {
         replace_bound_regions(tcx, isr, t)
     });
@@ -80,7 +79,7 @@ fn replace_bound_regions_in_fn_ty(
 
     return {isr: isr,
          self_info: new_self_info,
-         fn_ty: match ty::get(t_fn).sty { ty::ty_fn(ref o) => (*o),
+         fn_ty: match ty::get(t_fn).sty { ty::ty_fn(ref o) => /*bad*/copy *o,
           _ => tcx.sess.bug(~"replace_bound_regions_in_fn_ty: impossible")}};
 
 
diff --git a/src/librustc/middle/typeck/check/vtable.rs b/src/librustc/middle/typeck/check/vtable.rs
index 53d2084acab..0872b1445c3 100644
--- a/src/librustc/middle/typeck/check/vtable.rs
+++ b/src/librustc/middle/typeck/check/vtable.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::resolve;
 use middle::ty;
 use middle::typeck::check::{fn_ctxt, impl_self_ty};
@@ -95,7 +96,7 @@ fn lookup_vtables(vcx: &VtableContext,
                    ppaux::ty_to_str(tcx, trait_ty),
                    ty::substs_to_str(tcx, substs));
 
-            let new_substs = {self_ty: Some(*ty), ..*substs};
+            let new_substs = {self_ty: Some(*ty), ../*bad*/copy *substs};
             let trait_ty = ty::subst(tcx, &new_substs, trait_ty);
 
             debug!("after subst: %?",
@@ -129,14 +130,14 @@ fn lookup_vtables(vcx: &VtableContext,
 }
 
 fn fixup_substs(vcx: &VtableContext, location_info: &LocationInfo,
-                id: ast::def_id, substs: ty::substs,
+                id: ast::def_id, +substs: ty::substs,
                 is_early: bool) -> Option<ty::substs> {
     let tcx = vcx.tcx();
     // use a dummy type just to package up the substs that need fixing up
     let t = ty::mk_trait(tcx, id, substs, ty::vstore_slice(ty::re_static));
     do fixup_ty(vcx, location_info, t, is_early).map |t_f| {
         match ty::get(*t_f).sty {
-          ty::ty_trait(_, ref substs_f, _) => (*substs_f),
+          ty::ty_trait(_, ref substs_f, _) => (/*bad*/copy *substs_f),
           _ => fail ~"t_f should be a trait"
         }
     }
@@ -162,7 +163,8 @@ fn lookup_vtable(vcx: &VtableContext,
 
     let tcx = vcx.tcx();
     let (trait_id, trait_substs, trait_vstore) = match ty::get(trait_ty).sty {
-        ty::ty_trait(did, ref substs, vstore) => (did, (*substs), vstore),
+        ty::ty_trait(did, ref substs, vstore) =>
+            (did, (/*bad*/copy *substs), vstore),
         _ => tcx.sess.impossible_case(location_info.span,
                                       "lookup_vtable: \
                                        don't know how to handle a non-trait")
@@ -221,7 +223,7 @@ fn lookup_vtable(vcx: &VtableContext,
             relate_trait_tys(vcx, location_info, trait_ty, ty);
             if !allow_unsafe && !is_early {
                 for vec::each(*ty::trait_methods(tcx, did)) |m| {
-                    if ty::type_has_self(ty::mk_fn(tcx, m.fty)) {
+                    if ty::type_has_self(ty::mk_fn(tcx, /*bad*/copy m.fty)) {
                         tcx.sess.span_err(
                             location_info.span,
                             ~"a boxed trait with self types may not be \
@@ -235,7 +237,7 @@ fn lookup_vtable(vcx: &VtableContext,
                     }
                 }
             }
-            return Some(vtable_trait(did, (*substs).tps));
+            return Some(vtable_trait(did, /*bad*/copy (*substs).tps));
         }
 
         _ => {
@@ -349,7 +351,7 @@ fn lookup_vtable(vcx: &VtableContext,
                             // trait_substs. Now we extract out the
                             // types themselves from trait_substs.
 
-                            let trait_tps = trait_substs.tps;
+                            let trait_tps = /*bad*/copy trait_substs.tps;
 
                             debug!("Casting to a trait ty whose substs \
                                     (trait_tps) are %s",
@@ -368,7 +370,7 @@ fn lookup_vtable(vcx: &VtableContext,
                                                               trait_id,
                                                               substs,
                                                               is_early) {
-                                Some(ref substs) => (*substs),
+                                Some(ref substs) => (/*bad*/copy *substs),
                                 None => {
                                     assert is_early;
                                     // Bail out with a bogus answer
@@ -393,7 +395,7 @@ fn lookup_vtable(vcx: &VtableContext,
                                                              im.did).bounds;
                             connect_trait_tps(vcx,
                                               location_info,
-                                              substs_f.tps,
+                                              /*bad*/copy substs_f.tps,
                                               trait_tps,
                                               im.did,
                                               trait_vstore);
@@ -407,7 +409,8 @@ fn lookup_vtable(vcx: &VtableContext,
                             // of type substitutions for the target
                             // trait.
                             found.push(
-                                vtable_static(im.did, substs_f.tps,
+                                vtable_static(im.did,
+                                              /*bad*/copy substs_f.tps,
                                               subres));
                         }
                     }
@@ -416,14 +419,14 @@ fn lookup_vtable(vcx: &VtableContext,
 
             match found.len() {
                 0 => { /* fallthrough */ }
-                1 => { return Some(found[0]); }
+                1 => { return Some(/*bad*/copy found[0]); }
                 _ => {
                     if !is_early {
                         vcx.tcx().sess.span_err(
                             location_info.span,
                             ~"multiple applicable methods in scope");
                     }
-                    return Some(found[0]);
+                    return Some(/*bad*/copy found[0]);
                 }
             }
         }
@@ -518,7 +521,7 @@ fn early_resolve_expr(ex: @ast::expr, &&fcx: @fn_ctxt, is_early: bool) {
             let item_ty = ty::lookup_item_type(cx.tcx, did);
             debug!("early resolve expr: def %? %?, %?, %?", ex.id, did, def,
                    fcx.infcx().ty_to_str(item_ty.ty));
-            if has_trait_bounds(*item_ty.bounds) {
+            if has_trait_bounds(/*bad*/copy *item_ty.bounds) {
                 for item_ty.bounds.each |bounds| {
                     debug!("early_resolve_expr: looking up vtables for bound \
                             %s",
@@ -545,7 +548,7 @@ fn early_resolve_expr(ex: @ast::expr, &&fcx: @fn_ctxt, is_early: bool) {
       ast::expr_index(*) | ast::expr_method_call(*) => {
         match ty::method_call_bounds(cx.tcx, cx.method_map, ex.id) {
           Some(bounds) => {
-            if has_trait_bounds(*bounds) {
+            if has_trait_bounds(/*bad*/copy *bounds) {
                 let callee_id = match ex.node {
                   ast::expr_field(_, _, _) => ex.id,
                   _ => ex.callee_id
diff --git a/src/librustc/middle/typeck/check/writeback.rs b/src/librustc/middle/typeck/check/writeback.rs
index 84d3eea1b35..623c280ac22 100644
--- a/src/librustc/middle/typeck/check/writeback.rs
+++ b/src/librustc/middle/typeck/check/writeback.rs
@@ -12,6 +12,7 @@
 // unresolved type variables and replaces "ty_var" types with their
 // substitutions.
 
+
 use middle::pat_util;
 use middle::ty;
 use middle::typeck::check::{fn_ctxt, lookup_local};
@@ -154,7 +155,7 @@ fn visit_expr(e: @ast::expr, wbcx: wb_ctxt, v: wb_vt) {
     resolve_type_vars_for_node(wbcx, e.span, e.id);
     resolve_method_map_entry(wbcx.fcx, e.span, e.id);
     resolve_method_map_entry(wbcx.fcx, e.span, e.callee_id);
-    match e.node {
+    match /*bad*/copy e.node {
       ast::expr_fn(_, decl, _, _) |
       ast::expr_fn_block(decl, _, _) => {
           for vec::each(decl.inputs) |input| {
diff --git a/src/librustc/middle/typeck/coherence.rs b/src/librustc/middle/typeck/coherence.rs
index f6739ce1f1b..0116214b5f9 100644
--- a/src/librustc/middle/typeck/coherence.rs
+++ b/src/librustc/middle/typeck/coherence.rs
@@ -14,6 +14,7 @@
 // has at most one implementation for each type. Then we build a mapping from
 // each trait in the system to its implementations.
 
+
 use driver;
 use metadata::csearch::{ProvidedTraitMethodInfo, each_path, get_impl_traits};
 use metadata::csearch::{get_impls_for_mod};
@@ -510,10 +511,13 @@ impl CoherenceChecker {
             self_ty: None,
             tps: type_parameters
         };
-
         let monotype = subst(self.crate_context.tcx,
                              &substitutions,
                              polytype.ty);
+
+        // Get our type parameters back.
+        let { self_r: _, self_ty: _, tps: type_parameters } = substitutions;
+
         UniversalQuantificationResult {
             monotype: monotype,
             type_variables: move type_parameters,
@@ -583,7 +587,7 @@ impl CoherenceChecker {
     fn check_privileged_scopes(crate: @crate) {
         visit_crate(*crate, (), mk_vt(@{
             visit_item: |item, _context, visitor| {
-                match item.node {
+                match /*bad*/copy item.node {
                     item_mod(module_) => {
                         // Then visit the module items.
                         visit_mod(module_, item.span, item.id, (), visitor);
@@ -717,7 +721,7 @@ impl CoherenceChecker {
             }
         }
 
-        match item.node {
+        match /*bad*/copy item.node {
             item_impl(_, trait_refs, _, ast_methods) => {
                 let mut methods = ~[];
                 for ast_methods.each |ast_method| {
diff --git a/src/librustc/middle/typeck/collect.rs b/src/librustc/middle/typeck/collect.rs
index 930d159eefe..48c16a94212 100644
--- a/src/librustc/middle/typeck/collect.rs
+++ b/src/librustc/middle/typeck/collect.rs
@@ -62,7 +62,7 @@ fn collect_item_types(ccx: @crate_ctxt, crate: @ast::crate) {
         if crate_item.ident
             == ::syntax::parse::token::special_idents::intrinsic {
 
-            match crate_item.node {
+            match /*bad*/copy crate_item.node {
               ast::item_mod(m) => {
                 for m.items.each |intrinsic_item| {
                     let def_id = { crate: ast::local_crate,
@@ -150,7 +150,7 @@ fn get_enum_variant_types(ccx: @crate_ctxt,
         // constructors get turned into functions.
         let result_ty;
         match variant.node.kind {
-            ast::tuple_variant_kind(args) if args.len() > 0 => {
+            ast::tuple_variant_kind(ref args) if args.len() > 0 => {
                 let rs = type_rscope(rp);
                 let args = args.map(|va| {
                     let arg_ty = ccx.to_ty(rs, va.ty);
@@ -172,11 +172,18 @@ fn get_enum_variant_types(ccx: @crate_ctxt,
             }
             ast::struct_variant_kind(struct_def) => {
                 // XXX: Merge with computation of the the same value below?
-                let tpt = {bounds: ty_param_bounds(ccx, ty_params),
-                           region_param: rp,
-                           ty: enum_ty};
+                let tpt = {
+                    bounds: ty_param_bounds(ccx, /*bad*/copy ty_params),
+                    region_param: rp,
+                    ty: enum_ty
+                };
                 convert_struct(
-                    ccx, rp, struct_def, ty_params, tpt, variant.node.id);
+                    ccx,
+                    rp,
+                    struct_def,
+                    /*bad*/copy ty_params,
+                    tpt,
+                    variant.node.id);
                 // Compute the ctor arg types from the struct fields
                 let struct_fields = do struct_def.fields.map |struct_field| {
                     {mode: ast::expl(ast::by_val),
@@ -195,8 +202,8 @@ fn get_enum_variant_types(ccx: @crate_ctxt,
             ast::enum_variant_kind(ref enum_definition) => {
                 get_enum_variant_types(ccx,
                                        enum_ty,
-                                       enum_definition.variants,
-                                       ty_params,
+                                       /*bad*/copy enum_definition.variants,
+                                       /*bad*/copy ty_params,
                                        rp);
                 result_ty = None;
             }
@@ -205,9 +212,11 @@ fn get_enum_variant_types(ccx: @crate_ctxt,
         match result_ty {
             None => {}
             Some(result_ty) => {
-                let tpt = {bounds: ty_param_bounds(ccx, ty_params),
-                           region_param: rp,
-                           ty: result_ty};
+                let tpt = {
+                    bounds: ty_param_bounds(ccx, /*bad*/copy ty_params),
+                    region_param: rp,
+                    ty: result_ty
+                };
                 tcx.tcache.insert(local_def(variant.node.id), tpt);
                 write_ty_to_tcx(tcx, variant.node.id, result_ty);
             }
@@ -217,7 +226,7 @@ fn get_enum_variant_types(ccx: @crate_ctxt,
 
 fn ensure_trait_methods(ccx: @crate_ctxt, id: ast::node_id, trait_ty: ty::t) {
     fn store_methods<T>(ccx: @crate_ctxt, id: ast::node_id,
-                        stuff: ~[T], f: fn@(v: &T) -> ty::method) {
+                        stuff: ~[T], f: &fn(v: &T) -> ty::method) {
         ty::store_trait_methods(ccx.tcx, id, @vec::map(stuff, f));
     }
 
@@ -250,7 +259,9 @@ fn ensure_trait_methods(ccx: @crate_ctxt, id: ast::node_id, trait_ty: ty::t) {
 
         let substs = { self_r: None, self_ty: Some(self_param),
                        tps: non_shifted_trait_tps + shifted_method_tps };
-        let ty = ty::subst(ccx.tcx, &substs, ty::mk_fn(ccx.tcx, m.fty));
+        let ty = ty::subst(ccx.tcx,
+                           &substs,
+                           ty::mk_fn(ccx.tcx, /*bad*/copy m.fty));
         let bounds = @(*trait_bounds + ~[@~[ty::bound_trait(trait_ty)]]
                        + *m.tps);
         ccx.tcx.tcache.insert(local_def(am.id),
@@ -264,10 +275,10 @@ fn ensure_trait_methods(ccx: @crate_ctxt, id: ast::node_id, trait_ty: ty::t) {
     let region_paramd = tcx.region_paramd_items.find(id);
     match tcx.items.get(id) {
       ast_map::node_item(@{
-                node: ast::item_trait(params, _, ref ms),
+                node: ast::item_trait(ref params, _, ref ms),
                 _
             }, _) => {
-        store_methods::<ast::trait_method>(ccx, id, (*ms), |m| {
+        store_methods::<ast::trait_method>(ccx, id, (/*bad*/copy *ms), |m| {
             let def_id;
             match *m {
                 ast::required(ref ty_method) => {
@@ -276,7 +287,7 @@ fn ensure_trait_methods(ccx: @crate_ctxt, id: ast::node_id, trait_ty: ty::t) {
                 ast::provided(method) => def_id = local_def(method.id)
             }
 
-            let trait_bounds = ty_param_bounds(ccx, params);
+            let trait_bounds = ty_param_bounds(ccx, copy *params);
             let ty_m = trait_method_to_ty_method(*m);
             let method_ty = ty_of_ty_method(ccx, ty_m, region_paramd, def_id);
             if ty_m.self_ty.node == ast::sty_static {
@@ -430,7 +441,7 @@ fn compare_impl_method(tcx: ty::ctxt,
     //   that correspond to the parameters we will find on the impl
     // - replace self region with a fresh, dummy region
     let impl_fty = {
-        let impl_fty = ty::mk_fn(tcx, impl_m.fty);
+        let impl_fty = ty::mk_fn(tcx, /*bad*/copy impl_m.fty);
         debug!("impl_fty (pre-subst): %s", ppaux::ty_to_str(tcx, impl_fty));
         replace_bound_self(tcx, impl_fty, dummy_self_r)
     };
@@ -448,7 +459,7 @@ fn compare_impl_method(tcx: ty::ctxt,
             self_ty: Some(self_ty),
             tps: vec::append(trait_tps, dummy_tps)
         };
-        let trait_fty = ty::mk_fn(tcx, trait_m.fty);
+        let trait_fty = ty::mk_fn(tcx, /*bad*/copy trait_m.fty);
         debug!("trait_fty (pre-subst): %s", ppaux::ty_to_str(tcx, trait_fty));
         ty::subst(tcx, &substs, trait_fty)
     };
@@ -554,15 +565,15 @@ fn convert_methods(ccx: @crate_ctxt,
 
     let tcx = ccx.tcx;
     do vec::map(ms) |m| {
-        let bounds = ty_param_bounds(ccx, m.tps);
+        let bounds = ty_param_bounds(ccx, /*bad*/copy m.tps);
         let mty = ty_of_method(ccx, *m, rp);
-        let fty = ty::mk_fn(tcx, mty.fty);
+        let fty = ty::mk_fn(tcx, /*bad*/copy mty.fty);
         tcx.tcache.insert(
             local_def(m.id),
 
             // n.b.: the type of a method is parameterized by both
             // the tps on the receiver and those on the method itself
-            {bounds: @(vec::append(*rcvr_bounds, *bounds)),
+            {bounds: @(vec::append(/*bad*/copy *rcvr_bounds, *bounds)),
              region_param: rp,
              ty: fty});
         write_ty_to_tcx(tcx, m.id, fty);
@@ -576,17 +587,19 @@ fn convert(ccx: @crate_ctxt, it: @ast::item) {
     let rp = tcx.region_paramd_items.find(it.id);
     debug!("convert: item %s with id %d rp %?",
            tcx.sess.str_of(it.ident), it.id, rp);
-    match it.node {
+    match /*bad*/copy it.node {
       // These don't define types.
       ast::item_foreign_mod(_) | ast::item_mod(_) => {}
-      ast::item_enum(ref enum_definition, ty_params) => {
+      ast::item_enum(ref enum_definition, ref ty_params) => {
         let tpt = ty_of_item(ccx, it);
         write_ty_to_tcx(tcx, it.id, tpt.ty);
-        get_enum_variant_types(ccx, tpt.ty, (*enum_definition).variants,
-                               ty_params, rp);
+        get_enum_variant_types(ccx,
+                               tpt.ty,
+                               /*bad*/copy (*enum_definition).variants,
+                               /*bad*/copy *ty_params, rp);
       }
-      ast::item_impl(tps, trait_ref, selfty, ms) => {
-        let i_bounds = ty_param_bounds(ccx, tps);
+      ast::item_impl(ref tps, trait_ref, selfty, ref ms) => {
+        let i_bounds = ty_param_bounds(ccx, /*bad*/copy *tps);
         let selfty = ccx.to_ty(type_rscope(rp), selfty);
         write_ty_to_tcx(tcx, it.id, selfty);
         tcx.tcache.insert(local_def(it.id),
@@ -594,21 +607,24 @@ fn convert(ccx: @crate_ctxt, it: @ast::item) {
                            region_param: rp,
                            ty: selfty});
 
-        let cms = convert_methods(ccx, ms, rp, i_bounds);
+        // XXX: Bad copy of `ms` below.
+        let cms = convert_methods(ccx, /*bad*/copy *ms, rp, i_bounds);
         for trait_ref.each |t| {
-            check_methods_against_trait(ccx, tps, rp, selfty, *t, cms);
+            check_methods_against_trait(ccx, /*bad*/copy *tps, rp, selfty,
+                                        *t, /*bad*/copy cms);
         }
       }
-      ast::item_trait(tps, supertraits, ref trait_methods) => {
+      ast::item_trait(ref tps, ref supertraits, ref trait_methods) => {
         let tpt = ty_of_item(ccx, it);
         debug!("item_trait(it.id=%d, tpt.ty=%s)",
                it.id, ppaux::ty_to_str(tcx, tpt.ty));
         write_ty_to_tcx(tcx, it.id, tpt.ty);
         ensure_trait_methods(ccx, it.id, tpt.ty);
-        ensure_supertraits(ccx, it.id, it.span, rp, supertraits);
+        ensure_supertraits(ccx, it.id, it.span, rp, *supertraits);
 
-        let (_, provided_methods) = split_trait_methods((*trait_methods));
-        let {bounds, _} = mk_substs(ccx, tps, rp);
+        let (_, provided_methods) =
+            split_trait_methods(/*bad*/copy *trait_methods);
+        let {bounds, _} = mk_substs(ccx, /*bad*/copy *tps, rp);
         let _cms = convert_methods(ccx, provided_methods, rp, bounds);
         // FIXME (#2616): something like this, when we start having
         // trait inheritance?
@@ -637,7 +653,7 @@ fn convert(ccx: @crate_ctxt, it: @ast::item) {
 fn convert_struct(ccx: @crate_ctxt,
                   rp: Option<ty::region_variance>,
                   struct_def: @ast::struct_def,
-                  tps: ~[ast::ty_param],
+                  +tps: ~[ast::ty_param],
                   tpt: ty::ty_param_bounds_and_ty,
                   id: ast::node_id) {
     let tcx = ccx.tcx;
@@ -720,7 +736,7 @@ fn ty_of_method(ccx: @crate_ctxt,
                 m: @ast::method,
                 rp: Option<ty::region_variance>) -> ty::method {
     {ident: m.ident,
-     tps: ty_param_bounds(ccx, m.tps),
+     tps: ty_param_bounds(ccx, /*bad*/copy m.tps),
      fty: ty_of_fn_decl(ccx, type_rscope(rp), ast::ProtoBare,
                         m.purity, ast::Many,
                         /*bounds:*/ @~[], /*opt_region:*/ None,
@@ -735,7 +751,7 @@ fn ty_of_ty_method(self: @crate_ctxt,
                    rp: Option<ty::region_variance>,
                    id: ast::def_id) -> ty::method {
     {ident: m.ident,
-     tps: ty_param_bounds(self, m.tps),
+     tps: ty_param_bounds(self, /*bad*/copy m.tps),
      fty: ty_of_fn_decl(self, type_rscope(rp), ast::ProtoBare,
                         m.purity, ast::Many,
                         /*bounds:*/ @~[], /*opt_region:*/ None,
@@ -785,7 +801,7 @@ fn ty_of_item(ccx: @crate_ctxt, it: @ast::item)
       _ => {}
     }
     let rp = tcx.region_paramd_items.find(it.id);
-    match it.node {
+    match /*bad*/copy it.node {
       ast::item_const(t, _) => {
         let typ = ccx.to_ty(empty_rscope, t);
         let tpt = no_params(typ);
@@ -870,7 +886,7 @@ fn ty_of_item(ccx: @crate_ctxt, it: @ast::item)
 
 fn ty_of_foreign_item(ccx: @crate_ctxt, it: @ast::foreign_item)
     -> ty::ty_param_bounds_and_ty {
-    match it.node {
+    match /*bad*/copy it.node {
       ast::foreign_item_fn(fn_decl, purity, params) => {
         return ty_of_foreign_fn_decl(ccx, fn_decl, purity, params,
                                      local_def(it.id));
@@ -939,9 +955,8 @@ fn ty_param_bounds(ccx: @crate_ctxt,
 fn ty_of_foreign_fn_decl(ccx: @crate_ctxt,
                          decl: ast::fn_decl,
                          purity: ast::purity,
-                         ty_params: ~[ast::ty_param],
+                         +ty_params: ~[ast::ty_param],
                          def_id: ast::def_id) -> ty::ty_param_bounds_and_ty {
-
     let bounds = ty_param_bounds(ccx, ty_params);
     let rb = in_binding_rscope(empty_rscope);
     let input_tys = decl.inputs.map(|a| ty_of_arg(ccx, rb, *a, None) );
@@ -966,7 +981,8 @@ fn mk_ty_params(ccx: @crate_ctxt, atps: ~[ast::ty_param])
     -> {bounds: @~[ty::param_bounds], params: ~[ty::t]} {
 
     let mut i = 0u;
-    let bounds = ty_param_bounds(ccx, atps);
+    // XXX: Bad copy.
+    let bounds = ty_param_bounds(ccx, copy atps);
     {bounds: bounds,
      params: vec::map(atps, |atp| {
          let t = ty::mk_param(ccx.tcx, i, local_def(atp.id));
@@ -975,10 +991,10 @@ fn mk_ty_params(ccx: @crate_ctxt, atps: ~[ast::ty_param])
      })}
 }
 
-fn mk_substs(ccx: @crate_ctxt, atps: ~[ast::ty_param],
+fn mk_substs(ccx: @crate_ctxt,
+             +atps: ~[ast::ty_param],
              rp: Option<ty::region_variance>)
-    -> {bounds: @~[ty::param_bounds], substs: ty::substs} {
-
+          -> {bounds: @~[ty::param_bounds], substs: ty::substs} {
     let {bounds, params} = mk_ty_params(ccx, atps);
     let self_r = rscope::bound_self_region(rp);
     {bounds: bounds, substs: {self_r: self_r, self_ty: None, tps: params}}
diff --git a/src/librustc/middle/typeck/infer/assignment.rs b/src/librustc/middle/typeck/infer/assignment.rs
index a41c1efb6c3..9de71d22a31 100644
--- a/src/librustc/middle/typeck/infer/assignment.rs
+++ b/src/librustc/middle/typeck/infer/assignment.rs
@@ -58,6 +58,7 @@
 // A.  But this upper-bound might be stricter than what is truly
 // needed.
 
+
 use middle::ty;
 use middle::typeck::infer::combine::combine_fields;
 use middle::typeck::infer::to_str::ToStr;
@@ -84,7 +85,13 @@ impl Assign {
                b.to_str(self.infcx));
         let _r = indenter();
 
-        match (ty::get(a).sty, ty::get(b).sty) {
+        debug!("Assign.tys: copying first type");
+        let copy_a = copy ty::get(a).sty;
+        debug!("Assign.tys: copying second type");
+        let copy_b = copy ty::get(b).sty;
+        debug!("Assign.tys: performing match");
+
+        let r = match (copy_a, copy_b) {
             (ty::ty_bot, _) => {
                 Ok(None)
             }
@@ -119,7 +126,11 @@ impl Assign {
             (_, _) => {
                 self.assign_tys_or_sub(a, b, Some(a), Some(b))
             }
-        }
+        };
+
+        debug!("Assign.tys end");
+
+        move r
     }
 }
 
@@ -150,7 +161,8 @@ priv impl Assign {
 
         match (a_bnd, b_bnd) {
             (Some(a_bnd), Some(b_bnd)) => {
-                match (ty::get(a_bnd).sty, ty::get(b_bnd).sty) {
+                match (/*bad*/copy ty::get(a_bnd).sty,
+                       /*bad*/copy ty::get(b_bnd).sty) {
                     // check for a case where a non-region pointer (@, ~) is
                     // being assigned to a region pointer:
                     (ty::ty_box(_), ty::ty_rptr(r_b, mt_b)) => {
@@ -192,7 +204,7 @@ priv impl Assign {
                         let nr_b = ty::mk_fn(self.infcx.tcx, ty::FnTyBase {
                             meta: ty::FnMeta {proto: a_f.meta.proto,
                                               ..b_f.meta},
-                            sig: b_f.sig
+                            sig: /*bad*/copy b_f.sig
                         });
                         self.try_assign(0, ty::AutoBorrowFn,
                                         a, nr_b, m_imm, b_f.meta.region)
diff --git a/src/librustc/middle/typeck/infer/combine.rs b/src/librustc/middle/typeck/infer/combine.rs
index 6505b7f8384..e612a76b92d 100644
--- a/src/librustc/middle/typeck/infer/combine.rs
+++ b/src/librustc/middle/typeck/infer/combine.rs
@@ -54,8 +54,6 @@
 // terms of error reporting, although we do not do that properly right
 // now.
 
-#[warn(vecs_implicitly_copyable)];
-
 use middle::ty;
 use middle::ty::{FnTyBase, FnMeta, FnSig};
 use middle::typeck::infer::sub::Sub;
@@ -226,7 +224,7 @@ fn super_substs<C:combine>(
             do relate_region_param(self, did,
                                    a.self_r, b.self_r).chain |self_r|
             {
-                Ok({self_r: self_r, self_ty: self_ty, tps: tps})
+                Ok({self_r: self_r, self_ty: self_ty, tps: /*bad*/copy tps})
             }
         }
     }
@@ -345,10 +343,10 @@ fn super_fn_metas<C:combine>(
 }
 
 fn super_fn_sigs<C:combine>(
-    self: &C, a_f: &ty::FnSig, b_f: &ty::FnSig) -> cres<ty::FnSig>
-{
-    fn argvecs<C:combine>(self: &C, a_args: ~[ty::arg],
-                          b_args: ~[ty::arg]) -> cres<~[ty::arg]> {
+    self: &C, a_f: &ty::FnSig, b_f: &ty::FnSig) -> cres<ty::FnSig> {
+    fn argvecs<C:combine>(self: &C,
+                          +a_args: ~[ty::arg],
+                          +b_args: ~[ty::arg]) -> cres<~[ty::arg]> {
 
         if vec::same_length(a_args, b_args) {
             map_vec2(a_args, b_args, |a, b| self.args(*a, *b))
@@ -357,9 +355,10 @@ fn super_fn_sigs<C:combine>(
         }
     }
 
-    do argvecs(self, a_f.inputs, b_f.inputs).chain |inputs| {
+    do argvecs(self, /*bad*/copy a_f.inputs, /*bad*/copy b_f.inputs)
+            .chain |inputs| {
         do self.tys(a_f.output, b_f.output).chain |output| {
-            Ok(FnSig {inputs: inputs, output: output})
+            Ok(FnSig {inputs: /*bad*/copy inputs, output: output})
         }
     }
 }
@@ -378,7 +377,7 @@ fn super_tys<C:combine>(
     self: &C, a: ty::t, b: ty::t) -> cres<ty::t> {
 
     let tcx = self.infcx().tcx;
-    match (ty::get(a).sty, ty::get(b).sty) {
+    match (/*bad*/copy ty::get(a).sty, /*bad*/copy ty::get(b).sty) {
       // The "subtype" ought to be handling cases involving bot or var:
       (ty::ty_bot, _) |
       (_, ty::ty_bot) |
@@ -418,8 +417,8 @@ fn super_tys<C:combine>(
       (ty::ty_int(_), _) |
       (ty::ty_uint(_), _) |
       (ty::ty_float(_), _) => {
-        let as_ = ty::get(a).sty;
-        let bs = ty::get(b).sty;
+        let as_ = /*bad*/copy ty::get(a).sty;
+        let bs = /*bad*/copy ty::get(b).sty;
         if as_ == bs {
             Ok(a)
         } else {
@@ -454,7 +453,7 @@ fn super_tys<C:combine>(
       if a_id == b_id => {
         do self.substs(a_id, a_substs, b_substs).chain |substs| {
             do self.vstores(ty::terr_trait, a_vstore, b_vstore).chain |vs| {
-                Ok(ty::mk_trait(tcx, a_id, substs, vs))
+                Ok(ty::mk_trait(tcx, a_id, /*bad*/copy substs, vs))
             }
         }
       }
diff --git a/src/librustc/middle/typeck/infer/floating.rs b/src/librustc/middle/typeck/infer/floating.rs
index c5c19cd16e8..85a11a598e9 100644
--- a/src/librustc/middle/typeck/infer/floating.rs
+++ b/src/librustc/middle/typeck/infer/floating.rs
@@ -14,6 +14,7 @@ Code related to floating-point type inference.
 
 */
 
+
 use middle::ty;
 use middle::ty::ty_float;
 use middle::typeck::infer::to_str::ToStr;
diff --git a/src/librustc/middle/typeck/infer/glb.rs b/src/librustc/middle/typeck/infer/glb.rs
index 6a6a817e97e..f4139c4cf49 100644
--- a/src/librustc/middle/typeck/infer/glb.rs
+++ b/src/librustc/middle/typeck/infer/glb.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::typeck::infer::combine::*;
 use middle::typeck::infer::lattice::*;
diff --git a/src/librustc/middle/typeck/infer/lattice.rs b/src/librustc/middle/typeck/infer/lattice.rs
index c8d63ea796e..fae5feb369e 100644
--- a/src/librustc/middle/typeck/infer/lattice.rs
+++ b/src/librustc/middle/typeck/infer/lattice.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::typeck::infer::combine::*;
 use middle::typeck::infer::unify::*;
diff --git a/src/librustc/middle/typeck/infer/lub.rs b/src/librustc/middle/typeck/infer/lub.rs
index 7a402e2218d..53c9b263034 100644
--- a/src/librustc/middle/typeck/infer/lub.rs
+++ b/src/librustc/middle/typeck/infer/lub.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::typeck::infer::combine::*;
 use middle::typeck::infer::lattice::*;
diff --git a/src/librustc/middle/typeck/infer/macros.rs b/src/librustc/middle/typeck/infer/macros.rs
index 616df1e72c5..8cccf75d6dc 100644
--- a/src/librustc/middle/typeck/infer/macros.rs
+++ b/src/librustc/middle/typeck/infer/macros.rs
@@ -19,4 +19,4 @@ macro_rules! if_ok(
     )
 );
 
-}
\ No newline at end of file
+}
diff --git a/src/librustc/middle/typeck/infer/resolve.rs b/src/librustc/middle/typeck/infer/resolve.rs
index 2448a49444b..da4c02b9e35 100644
--- a/src/librustc/middle/typeck/infer/resolve.rs
+++ b/src/librustc/middle/typeck/infer/resolve.rs
@@ -46,6 +46,7 @@
 // future).  If you want to resolve everything but one type, you are
 // probably better off writing `resolve_all - resolve_ivar`.
 
+
 use middle::ty;
 use middle::typeck::infer::floating::*;
 use middle::typeck::infer::floating;
@@ -110,7 +111,8 @@ impl resolve_state {
         assert vec::is_empty(self.v_seen);
         match self.err {
           None => {
-            debug!("Resolved to %s (modes=%x)",
+            debug!("Resolved to %s + %s (modes=%x)",
+                   ty_to_str(self.infcx.tcx, rty),
                    ty_to_str(self.infcx.tcx, rty),
                    self.modes);
             return Ok(rty);
@@ -133,7 +135,7 @@ impl resolve_state {
         indent(fn&() -> ty::t {
             if !ty::type_needs_infer(typ) { return typ; }
 
-            match ty::get(typ).sty {
+            match copy ty::get(typ).sty {
               ty::ty_infer(TyVar(vid)) => {
                 self.resolve_ty_var(vid)
               }
diff --git a/src/librustc/middle/typeck/infer/sub.rs b/src/librustc/middle/typeck/infer/sub.rs
index b87f42490e2..cc7733231ed 100644
--- a/src/librustc/middle/typeck/infer/sub.rs
+++ b/src/librustc/middle/typeck/infer/sub.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::typeck::infer::combine::*;
 use middle::typeck::infer::to_str::ToStr;
diff --git a/src/librustc/middle/typeck/infer/test.rs b/src/librustc/middle/typeck/infer/test.rs
index 13e36c9169b..c3d2c8e99f7 100644
--- a/src/librustc/middle/typeck/infer/test.rs
+++ b/src/librustc/middle/typeck/infer/test.rs
@@ -16,6 +16,7 @@ Note: This module is only compiled when doing unit testing.
 
 */
 
+
 use std::getopts;
 use std::map::HashMap;
 use std::getopts;
diff --git a/src/librustc/middle/typeck/infer/to_str.rs b/src/librustc/middle/typeck/infer/to_str.rs
index 99b1dab6398..73352b802d6 100644
--- a/src/librustc/middle/typeck/infer/to_str.rs
+++ b/src/librustc/middle/typeck/infer/to_str.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::typeck::infer::integral::int_ty_set;
 use middle::typeck::infer::floating::float_ty_set;
diff --git a/src/librustc/middle/typeck/infer/unify.rs b/src/librustc/middle/typeck/infer/unify.rs
index 90fb9e47b65..8056c2c6bb3 100644
--- a/src/librustc/middle/typeck/infer/unify.rs
+++ b/src/librustc/middle/typeck/infer/unify.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::typeck::infer::combine::combine;
 use middle::typeck::infer::floating::*;
diff --git a/src/librustc/middle/typeck/mod.rs b/src/librustc/middle/typeck/mod.rs
index a31563a6de0..adb6fc8baf7 100644
--- a/src/librustc/middle/typeck/mod.rs
+++ b/src/librustc/middle/typeck/mod.rs
@@ -347,7 +347,8 @@ fn check_main_fn_ty(ccx: @crate_ctxt,
             match tcx.items.find(main_id) {
                 Some(ast_map::node_item(it,_)) => {
                     match it.node {
-                        ast::item_fn(_,_,ps,_) if vec::is_not_empty(ps) => {
+                        ast::item_fn(_, _, ref ps, _)
+                        if vec::is_not_empty(*ps) => {
                             tcx.sess.span_err(
                                 main_span,
                                 ~"main function is not allowed \
diff --git a/src/librustc/middle/typeck/rscope.rs b/src/librustc/middle/typeck/rscope.rs
index 8a1a5672446..ecd73b4783a 100644
--- a/src/librustc/middle/typeck/rscope.rs
+++ b/src/librustc/middle/typeck/rscope.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 
 use core::result::Result;
diff --git a/src/librustc/rustc.rc b/src/librustc/rustc.rc
index 9f5866a210b..271d43087f3 100644
--- a/src/librustc/rustc.rc
+++ b/src/librustc/rustc.rc
@@ -22,7 +22,7 @@
 #[legacy_modes];
 #[legacy_exports];
 
-#[allow(vecs_implicitly_copyable)];
+#[allow(non_implicitly_copyable_typarams)];
 #[allow(non_camel_case_types)];
 #[allow(deprecated_mode)];
 #[warn(deprecated_pattern)];
@@ -262,7 +262,7 @@ Available lint options:
 fn describe_debug_flags() {
     io::println(fmt!("\nAvailable debug options:\n"));
     for session::debugging_opts_map().each |pair| {
-        let (name, desc, _) = *pair;
+        let (name, desc, _) = /*bad*/copy *pair;
         io::println(fmt!("    -Z %-20s -- %s", name, desc));
     }
 }
@@ -271,7 +271,7 @@ fn run_compiler(args: &~[~str], demitter: diagnostic::emitter) {
     // Don't display log spew by default. Can override with RUST_LOG.
     logging::console_off();
 
-    let mut args = *args;
+    let mut args = /*bad*/copy *args;
     let binary = args.shift();
 
     if args.is_empty() { usage(binary); return; }
@@ -308,7 +308,7 @@ fn run_compiler(args: &~[~str], demitter: diagnostic::emitter) {
     let input = match vec::len(matches.free) {
       0u => early_error(demitter, ~"no input filename given"),
       1u => {
-        let ifile = matches.free[0];
+        let ifile = /*bad*/copy matches.free[0];
         if ifile == ~"-" {
             let src = str::from_bytes(io::stdin().read_whole_stream());
             str_input(src)
@@ -319,7 +319,8 @@ fn run_compiler(args: &~[~str], demitter: diagnostic::emitter) {
       _ => early_error(demitter, ~"multiple input filenames provided")
     };
 
-    let sopts = build_session_options(binary, matches, demitter);
+    // XXX: Bad copy.
+    let sopts = build_session_options(copy binary, matches, demitter);
     let sess = build_session(sopts, demitter);
     let odir = getopts::opt_maybe_str(matches, ~"out-dir");
     let odir = odir.map(|o| Path(*o));
diff --git a/src/librustc/util/common.rs b/src/librustc/util/common.rs
index d32c2856ea4..cd71bb099fe 100644
--- a/src/librustc/util/common.rs
+++ b/src/librustc/util/common.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use syntax::ast;
 use syntax::codemap::{span};
 use syntax::visit;
@@ -101,7 +102,7 @@ fn is_main_name(path: syntax::ast_map::path) -> bool {
     )
 }
 
-fn pluralize(n: uint, s: ~str) -> ~str {
+fn pluralize(n: uint, +s: ~str) -> ~str {
     if n == 1 { s }
     else { str::concat([s, ~"s"]) }
 }
diff --git a/src/librustc/util/ppaux.rs b/src/librustc/util/ppaux.rs
index 5515c534d11..b5609f72523 100644
--- a/src/librustc/util/ppaux.rs
+++ b/src/librustc/util/ppaux.rs
@@ -8,6 +8,7 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+
 use middle::ty;
 use middle::ty::{arg, canon_mode};
 use middle::ty::{bound_copy, bound_const, bound_durable, bound_owned,
@@ -354,14 +355,14 @@ fn ty_to_str(cx: ctxt, typ: t) -> ~str {
     }
 
     // if there is an id, print that instead of the structural type:
-    for ty::type_def_id(typ).each |def_id| {
+    /*for ty::type_def_id(typ).each |def_id| {
         // note that this typedef cannot have type parameters
         return ast_map::path_to_str(ty::item_path(cx, *def_id),
                                     cx.sess.intr());
-    }
+    }*/
 
     // pretty print the structural type representation:
-    return match ty::get(typ).sty {
+    return match /*bad*/copy ty::get(typ).sty {
       ty_nil => ~"()",
       ty_bot => ~"_|_",
       ty_bool => ~"bool",
@@ -395,7 +396,7 @@ fn ty_to_str(cx: ctxt, typ: t) -> ~str {
                   f.meta.purity,
                   f.meta.onceness,
                   None,
-                  f.sig.inputs,
+                  /*bad*/copy f.sig.inputs,
                   f.sig.output,
                   f.meta.ret_style)
       }
@@ -408,12 +409,15 @@ fn ty_to_str(cx: ctxt, typ: t) -> ~str {
       ty_enum(did, ref substs) | ty_struct(did, ref substs) => {
         let path = ty::item_path(cx, did);
         let base = ast_map::path_to_str(path, cx.sess.intr());
-        parameterized(cx, base, (*substs).self_r, (*substs).tps)
+        parameterized(cx, base, (*substs).self_r, /*bad*/copy (*substs).tps)
       }
       ty_trait(did, ref substs, vs) => {
         let path = ty::item_path(cx, did);
         let base = ast_map::path_to_str(path, cx.sess.intr());
-        let result = parameterized(cx, base, (*substs).self_r, (*substs).tps);
+        let result = parameterized(cx,
+                                   base,
+                                   substs.self_r,
+                                   /*bad*/copy substs.tps);
         vstore_ty_to_str(cx, result, vs)
       }
       ty_evec(mt, vs) => {