Auto merge of #59564 - bjorn3:move_link_to_cg_ssa, r=eddyb

Move back::link and debuginfo::type_names to cg ssa

r? @eddyb

19 files changed, 1620 insertions, 1599 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 37761f29708..72a05753d09 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2634,6 +2634,7 @@ dependencies = [
  "serialize 0.0.0",
  "syntax 0.0.0",
  "syntax_pos 0.0.0",
+ "tempfile 3.0.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
diff --git a/src/librustc_codegen_llvm/back/archive.rs b/src/librustc_codegen_llvm/back/archive.rs
index 3fb9d4b5b77..e0e26e9af25 100644
--- a/src/librustc_codegen_llvm/back/archive.rs
+++ b/src/librustc_codegen_llvm/back/archive.rs
@@ -7,14 +7,13 @@ use std::path::{Path, PathBuf};
 use std::ptr;
 use std::str;
 
-use crate::back::bytecode::RLIB_BYTECODE_EXTENSION;
 use crate::llvm::archive_ro::{ArchiveRO, Child};
 use crate::llvm::{self, ArchiveKind};
-use crate::metadata::METADATA_FILENAME;
-use rustc_codegen_ssa::back::archive::find_library;
+use rustc_codegen_ssa::{METADATA_FILENAME, RLIB_BYTECODE_EXTENSION};
+use rustc_codegen_ssa::back::archive::{ArchiveBuilder, find_library};
 use rustc::session::Session;
 
-pub struct ArchiveConfig<'a> {
+struct ArchiveConfig<'a> {
     pub sess: &'a Session,
     pub dst: PathBuf,
     pub src: Option<PathBuf>,
@@ -23,7 +22,7 @@ pub struct ArchiveConfig<'a> {
 
 /// Helper for adding many files to an archive.
 #[must_use = "must call build() to finish building the archive"]
-pub struct ArchiveBuilder<'a> {
+pub struct LlvmArchiveBuilder<'a> {
     config: ArchiveConfig<'a>,
     removals: Vec<String>,
     additions: Vec<Addition>,
@@ -49,11 +48,26 @@ fn is_relevant_child(c: &Child<'_>) -> bool {
     }
 }
 
-impl<'a> ArchiveBuilder<'a> {
+fn archive_config<'a>(sess: &'a Session,
+                      output: &Path,
+                      input: Option<&Path>) -> ArchiveConfig<'a> {
+    use rustc_codegen_ssa::back::link::archive_search_paths;
+    ArchiveConfig {
+        sess,
+        dst: output.to_path_buf(),
+        src: input.map(|p| p.to_path_buf()),
+        lib_search_paths: archive_search_paths(sess),
+    }
+}
+
+impl<'a> ArchiveBuilder<'a> for LlvmArchiveBuilder<'a> {
     /// Creates a new static archive, ready for modifying the archive specified
     /// by `config`.
-    pub fn new(config: ArchiveConfig<'a>) -> ArchiveBuilder<'a> {
-        ArchiveBuilder {
+    fn new(sess: &'a Session,
+            output: &Path,
+            input: Option<&Path>) -> LlvmArchiveBuilder<'a> {
+        let config = archive_config(sess, output, input);
+        LlvmArchiveBuilder {
             config,
             removals: Vec::new(),
             additions: Vec::new(),
@@ -63,12 +77,12 @@ impl<'a> ArchiveBuilder<'a> {
     }
 
     /// Removes a file from this archive
-    pub fn remove_file(&mut self, file: &str) {
+    fn remove_file(&mut self, file: &str) {
         self.removals.push(file.to_string());
     }
 
     /// Lists all files in an archive
-    pub fn src_files(&mut self) -> Vec<String> {
+    fn src_files(&mut self) -> Vec<String> {
         if self.src_archive().is_none() {
             return Vec::new()
         }
@@ -84,18 +98,9 @@ impl<'a> ArchiveBuilder<'a> {
                .collect()
     }
 
-    fn src_archive(&mut self) -> Option<&ArchiveRO> {
-        if let Some(ref a) = self.src_archive {
-            return a.as_ref()
-        }
-        let src = self.config.src.as_ref()?;
-        self.src_archive = Some(ArchiveRO::open(src).ok());
-        self.src_archive.as_ref().unwrap().as_ref()
-    }
-
     /// Adds all of the contents of a native library to this archive. This will
     /// search in the relevant locations for a library named `name`.
-    pub fn add_native_library(&mut self, name: &str) {
+    fn add_native_library(&mut self, name: &str) {
         let location = find_library(name, &self.config.lib_search_paths,
                                     self.config.sess);
         self.add_archive(&location, |_| false).unwrap_or_else(|e| {
@@ -109,7 +114,7 @@ impl<'a> ArchiveBuilder<'a> {
     ///
     /// This ignores adding the bytecode from the rlib, and if LTO is enabled
     /// then the object file also isn't added.
-    pub fn add_rlib(&mut self,
+    fn add_rlib(&mut self,
                     rlib: &Path,
                     name: &str,
                     lto: bool,
@@ -141,23 +146,8 @@ impl<'a> ArchiveBuilder<'a> {
         })
     }
 
-    fn add_archive<F>(&mut self, archive: &Path, skip: F)
-                      -> io::Result<()>
-        where F: FnMut(&str) -> bool + 'static
-    {
-        let archive = match ArchiveRO::open(archive) {
-            Ok(ar) => ar,
-            Err(e) => return Err(io::Error::new(io::ErrorKind::Other, e)),
-        };
-        self.additions.push(Addition::Archive {
-            archive,
-            skip: Box::new(skip),
-        });
-        Ok(())
-    }
-
     /// Adds an arbitrary file to this archive
-    pub fn add_file(&mut self, file: &Path) {
+    fn add_file(&mut self, file: &Path) {
         let name = file.file_name().unwrap().to_str().unwrap();
         self.additions.push(Addition::File {
             path: file.to_path_buf(),
@@ -167,13 +157,13 @@ impl<'a> ArchiveBuilder<'a> {
 
     /// Indicate that the next call to `build` should update all symbols in
     /// the archive (equivalent to running 'ar s' over it).
-    pub fn update_symbols(&mut self) {
+    fn update_symbols(&mut self) {
         self.should_update_symbols = true;
     }
 
     /// Combine the provided files, rlibs, and native libraries into a single
     /// `Archive`.
-    pub fn build(&mut self) {
+    fn build(mut self) {
         let kind = self.llvm_archive_kind().unwrap_or_else(|kind|
             self.config.sess.fatal(&format!("Don't know how to build archive of type: {}", kind)));
 
@@ -182,6 +172,32 @@ impl<'a> ArchiveBuilder<'a> {
         }
 
     }
+}
+
+impl<'a> LlvmArchiveBuilder<'a> {
+    fn src_archive(&mut self) -> Option<&ArchiveRO> {
+        if let Some(ref a) = self.src_archive {
+            return a.as_ref()
+        }
+        let src = self.config.src.as_ref()?;
+        self.src_archive = Some(ArchiveRO::open(src).ok());
+        self.src_archive.as_ref().unwrap().as_ref()
+    }
+
+    fn add_archive<F>(&mut self, archive: &Path, skip: F)
+                      -> io::Result<()>
+        where F: FnMut(&str) -> bool + 'static
+    {
+        let archive = match ArchiveRO::open(archive) {
+            Ok(ar) => ar,
+            Err(e) => return Err(io::Error::new(io::ErrorKind::Other, e)),
+        };
+        self.additions.push(Addition::Archive {
+            archive,
+            skip: Box::new(skip),
+        });
+        Ok(())
+    }
 
     fn llvm_archive_kind(&self) -> Result<ArchiveKind, &str> {
         let kind = &*self.config.sess.target.target.options.archive_format;
diff --git a/src/librustc_codegen_llvm/back/bytecode.rs b/src/librustc_codegen_llvm/back/bytecode.rs
index 8b288c45336..397cdecbb6f 100644
--- a/src/librustc_codegen_llvm/back/bytecode.rs
+++ b/src/librustc_codegen_llvm/back/bytecode.rs
@@ -37,8 +37,6 @@ pub const RLIB_BYTECODE_OBJECT_MAGIC: &[u8] = b"RUST_OBJECT";
 // The version number this compiler will write to bytecode objects in rlibs
 pub const RLIB_BYTECODE_OBJECT_VERSION: u8 = 2;
 
-pub const RLIB_BYTECODE_EXTENSION: &str = "bc.z";
-
 pub fn encode(identifier: &str, bytecode: &[u8]) -> Vec<u8> {
     let mut encoded = Vec::new();
 
diff --git a/src/librustc_codegen_llvm/back/link.rs b/src/librustc_codegen_llvm/back/link.rs
deleted file mode 100644
index 6a3c2adc856..00000000000
--- a/src/librustc_codegen_llvm/back/link.rs
+++ /dev/null
@@ -1,1494 +0,0 @@
-use super::archive::{ArchiveBuilder, ArchiveConfig};
-use super::bytecode::RLIB_BYTECODE_EXTENSION;
-use super::rpath::RPathConfig;
-use super::rpath;
-use crate::back::wasm;
-use crate::metadata::METADATA_FILENAME;
-use crate::context::get_reloc_model;
-use crate::llvm;
-use rustc_codegen_ssa::back::linker::Linker;
-use rustc_codegen_ssa::back::link::{remove, ignored_for_lto, each_linked_rlib, linker_and_flavor,
-    get_linker};
-use rustc_codegen_ssa::back::command::Command;
-use rustc::session::config::{self, DebugInfo, OutputFilenames, OutputType, PrintRequest};
-use rustc::session::config::{RUST_CGU_EXT, Lto, Sanitizer};
-use rustc::session::filesearch;
-use rustc::session::search_paths::PathKind;
-use rustc::session::Session;
-use rustc::middle::cstore::{NativeLibrary, NativeLibraryKind};
-use rustc::middle::dependency_format::Linkage;
-use rustc_codegen_ssa::CodegenResults;
-use rustc::util::common::{time, time_ext};
-use rustc_fs_util::fix_windows_verbatim_for_gcc;
-use rustc::hir::def_id::CrateNum;
-use tempfile::{Builder as TempFileBuilder, TempDir};
-use rustc_target::spec::{PanicStrategy, RelroLevel, LinkerFlavor};
-use rustc_data_structures::fx::FxHashSet;
-
-use std::ascii;
-use std::char;
-use std::env;
-use std::fmt;
-use std::fs;
-use std::io;
-use std::iter;
-use std::path::{Path, PathBuf};
-use std::process::{Output, Stdio};
-use std::str;
-use syntax::attr;
-
-pub use rustc_codegen_utils::link::{find_crate_name, filename_for_input, default_output_for_target,
-                                    invalid_output_for_target, filename_for_metadata,
-                                    out_filename, check_file_is_writeable};
-
-
-/// Performs the linkage portion of the compilation phase. This will generate all
-/// of the requested outputs for this compilation session.
-pub(crate) fn link_binary(sess: &Session,
-                          codegen_results: &CodegenResults,
-                          outputs: &OutputFilenames,
-                          crate_name: &str) -> Vec<PathBuf> {
-    let mut out_filenames = Vec::new();
-    for &crate_type in sess.crate_types.borrow().iter() {
-        // Ignore executable crates if we have -Z no-codegen, as they will error.
-        let output_metadata = sess.opts.output_types.contains_key(&OutputType::Metadata);
-        if (sess.opts.debugging_opts.no_codegen || !sess.opts.output_types.should_codegen()) &&
-           !output_metadata &&
-           crate_type == config::CrateType::Executable {
-            continue;
-        }
-
-        if invalid_output_for_target(sess, crate_type) {
-           bug!("invalid output type `{:?}` for target os `{}`",
-                crate_type, sess.opts.target_triple);
-        }
-        let out_files = link_binary_output(sess,
-                                           codegen_results,
-                                           crate_type,
-                                           outputs,
-                                           crate_name);
-        out_filenames.extend(out_files);
-    }
-
-    // Remove the temporary object file and metadata if we aren't saving temps
-    if !sess.opts.cg.save_temps {
-        if sess.opts.output_types.should_codegen() && !preserve_objects_for_their_debuginfo(sess) {
-            for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
-                remove(sess, obj);
-            }
-        }
-        for obj in codegen_results.modules.iter().filter_map(|m| m.bytecode_compressed.as_ref()) {
-            remove(sess, obj);
-        }
-        if let Some(ref obj) = codegen_results.metadata_module.object {
-            remove(sess, obj);
-        }
-        if let Some(ref allocator) = codegen_results.allocator_module {
-            if let Some(ref obj) = allocator.object {
-                remove(sess, obj);
-            }
-            if let Some(ref bc) = allocator.bytecode_compressed {
-                remove(sess, bc);
-            }
-        }
-    }
-
-    out_filenames
-}
-
-/// Returns a boolean indicating whether we should preserve the object files on
-/// the filesystem for their debug information. This is often useful with
-/// split-dwarf like schemes.
-fn preserve_objects_for_their_debuginfo(sess: &Session) -> bool {
-    // If the objects don't have debuginfo there's nothing to preserve.
-    if sess.opts.debuginfo == DebugInfo::None {
-        return false
-    }
-
-    // If we're only producing artifacts that are archives, no need to preserve
-    // the objects as they're losslessly contained inside the archives.
-    let output_linked = sess.crate_types.borrow()
-        .iter()
-        .any(|&x| x != config::CrateType::Rlib && x != config::CrateType::Staticlib);
-    if !output_linked {
-        return false
-    }
-
-    // If we're on OSX then the equivalent of split dwarf is turned on by
-    // default. The final executable won't actually have any debug information
-    // except it'll have pointers to elsewhere. Historically we've always run
-    // `dsymutil` to "link all the dwarf together" but this is actually sort of
-    // a bummer for incremental compilation! (the whole point of split dwarf is
-    // that you don't do this sort of dwarf link).
-    //
-    // Basically as a result this just means that if we're on OSX and we're
-    // *not* running dsymutil then the object files are the only source of truth
-    // for debug information, so we must preserve them.
-    if sess.target.target.options.is_like_osx {
-        match sess.opts.debugging_opts.run_dsymutil {
-            // dsymutil is not being run, preserve objects
-            Some(false) => return true,
-
-            // dsymutil is being run, no need to preserve the objects
-            Some(true) => return false,
-
-            // The default historical behavior was to always run dsymutil, so
-            // we're preserving that temporarily, but we're likely to switch the
-            // default soon.
-            None => return false,
-        }
-    }
-
-    false
-}
-
-fn link_binary_output(sess: &Session,
-                      codegen_results: &CodegenResults,
-                      crate_type: config::CrateType,
-                      outputs: &OutputFilenames,
-                      crate_name: &str) -> Vec<PathBuf> {
-    for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
-        check_file_is_writeable(obj, sess);
-    }
-
-    let mut out_filenames = vec![];
-
-    if outputs.outputs.contains_key(&OutputType::Metadata) {
-        let out_filename = filename_for_metadata(sess, crate_name, outputs);
-        // To avoid races with another rustc process scanning the output directory,
-        // we need to write the file somewhere else and atomically move it to its
-        // final destination, with a `fs::rename` call. In order for the rename to
-        // always succeed, the temporary file needs to be on the same filesystem,
-        // which is why we create it inside the output directory specifically.
-        let metadata_tmpdir = TempFileBuilder::new()
-            .prefix("rmeta")
-            .tempdir_in(out_filename.parent().unwrap())
-            .unwrap_or_else(|err| sess.fatal(&format!("couldn't create a temp dir: {}", err)));
-        let metadata = emit_metadata(sess, codegen_results, &metadata_tmpdir);
-        if let Err(e) = fs::rename(metadata, &out_filename) {
-            sess.fatal(&format!("failed to write {}: {}", out_filename.display(), e));
-        }
-        out_filenames.push(out_filename);
-    }
-
-    let tmpdir = TempFileBuilder::new().prefix("rustc").tempdir().unwrap_or_else(|err|
-        sess.fatal(&format!("couldn't create a temp dir: {}", err)));
-
-    if outputs.outputs.should_codegen() {
-        let out_filename = out_filename(sess, crate_type, outputs, crate_name);
-        match crate_type {
-            config::CrateType::Rlib => {
-                link_rlib(sess,
-                          codegen_results,
-                          RlibFlavor::Normal,
-                          &out_filename,
-                          &tmpdir).build();
-            }
-            config::CrateType::Staticlib => {
-                link_staticlib(sess, codegen_results, &out_filename, &tmpdir);
-            }
-            _ => {
-                link_natively(sess, crate_type, &out_filename, codegen_results, tmpdir.path());
-            }
-        }
-        out_filenames.push(out_filename);
-    }
-
-    if sess.opts.cg.save_temps {
-        let _ = tmpdir.into_path();
-    }
-
-    out_filenames
-}
-
-fn archive_search_paths(sess: &Session) -> Vec<PathBuf> {
-    sess.target_filesearch(PathKind::Native).search_path_dirs()
-}
-
-fn archive_config<'a>(sess: &'a Session,
-                      output: &Path,
-                      input: Option<&Path>) -> ArchiveConfig<'a> {
-    ArchiveConfig {
-        sess,
-        dst: output.to_path_buf(),
-        src: input.map(|p| p.to_path_buf()),
-        lib_search_paths: archive_search_paths(sess),
-    }
-}
-
-/// We use a temp directory here to avoid races between concurrent rustc processes,
-/// such as builds in the same directory using the same filename for metadata while
-/// building an `.rlib` (stomping over one another), or writing an `.rmeta` into a
-/// directory being searched for `extern crate` (observing an incomplete file).
-/// The returned path is the temporary file containing the complete metadata.
-fn emit_metadata<'a>(
-    sess: &'a Session,
-    codegen_results: &CodegenResults,
-    tmpdir: &TempDir
-) -> PathBuf {
-    let out_filename = tmpdir.path().join(METADATA_FILENAME);
-    let result = fs::write(&out_filename, &codegen_results.metadata.raw_data);
-
-    if let Err(e) = result {
-        sess.fatal(&format!("failed to write {}: {}", out_filename.display(), e));
-    }
-
-    out_filename
-}
-
-enum RlibFlavor {
-    Normal,
-    StaticlibBase,
-}
-
-// Create an 'rlib'
-//
-// An rlib in its current incarnation is essentially a renamed .a file. The
-// rlib primarily contains the object file of the crate, but it also contains
-// all of the object files from native libraries. This is done by unzipping
-// native libraries and inserting all of the contents into this archive.
-fn link_rlib<'a>(sess: &'a Session,
-                 codegen_results: &CodegenResults,
-                 flavor: RlibFlavor,
-                 out_filename: &Path,
-                 tmpdir: &TempDir) -> ArchiveBuilder<'a> {
-    info!("preparing rlib to {:?}", out_filename);
-    let mut ab = ArchiveBuilder::new(archive_config(sess, out_filename, None));
-
-    for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
-        ab.add_file(obj);
-    }
-
-    // Note that in this loop we are ignoring the value of `lib.cfg`. That is,
-    // we may not be configured to actually include a static library if we're
-    // adding it here. That's because later when we consume this rlib we'll
-    // decide whether we actually needed the static library or not.
-    //
-    // To do this "correctly" we'd need to keep track of which libraries added
-    // which object files to the archive. We don't do that here, however. The
-    // #[link(cfg(..))] feature is unstable, though, and only intended to get
-    // liblibc working. In that sense the check below just indicates that if
-    // there are any libraries we want to omit object files for at link time we
-    // just exclude all custom object files.
-    //
-    // Eventually if we want to stabilize or flesh out the #[link(cfg(..))]
-    // feature then we'll need to figure out how to record what objects were
-    // loaded from the libraries found here and then encode that into the
-    // metadata of the rlib we're generating somehow.
-    for lib in codegen_results.crate_info.used_libraries.iter() {
-        match lib.kind {
-            NativeLibraryKind::NativeStatic => {}
-            NativeLibraryKind::NativeStaticNobundle |
-            NativeLibraryKind::NativeFramework |
-            NativeLibraryKind::NativeUnknown => continue,
-        }
-        if let Some(name) = lib.name {
-            ab.add_native_library(&name.as_str());
-        }
-    }
-
-    // After adding all files to the archive, we need to update the
-    // symbol table of the archive.
-    ab.update_symbols();
-
-    // Note that it is important that we add all of our non-object "magical
-    // files" *after* all of the object files in the archive. The reason for
-    // this is as follows:
-    //
-    // * When performing LTO, this archive will be modified to remove
-    //   objects from above. The reason for this is described below.
-    //
-    // * When the system linker looks at an archive, it will attempt to
-    //   determine the architecture of the archive in order to see whether its
-    //   linkable.
-    //
-    //   The algorithm for this detection is: iterate over the files in the
-    //   archive. Skip magical SYMDEF names. Interpret the first file as an
-    //   object file. Read architecture from the object file.
-    //
-    // * As one can probably see, if "metadata" and "foo.bc" were placed
-    //   before all of the objects, then the architecture of this archive would
-    //   not be correctly inferred once 'foo.o' is removed.
-    //
-    // Basically, all this means is that this code should not move above the
-    // code above.
-    match flavor {
-        RlibFlavor::Normal => {
-            // Instead of putting the metadata in an object file section, rlibs
-            // contain the metadata in a separate file.
-            ab.add_file(&emit_metadata(sess, codegen_results, tmpdir));
-
-            // For LTO purposes, the bytecode of this library is also inserted
-            // into the archive.
-            for bytecode in codegen_results
-                .modules
-                .iter()
-                .filter_map(|m| m.bytecode_compressed.as_ref())
-            {
-                ab.add_file(bytecode);
-            }
-
-            // After adding all files to the archive, we need to update the
-            // symbol table of the archive. This currently dies on macOS (see
-            // #11162), and isn't necessary there anyway
-            if !sess.target.target.options.is_like_osx {
-                ab.update_symbols();
-            }
-        }
-
-        RlibFlavor::StaticlibBase => {
-            let obj = codegen_results.allocator_module
-                .as_ref()
-                .and_then(|m| m.object.as_ref());
-            if let Some(obj) = obj {
-                ab.add_file(obj);
-            }
-        }
-    }
-
-    ab
-}
-
-// Create a static archive
-//
-// This is essentially the same thing as an rlib, but it also involves adding
-// all of the upstream crates' objects into the archive. This will slurp in
-// all of the native libraries of upstream dependencies as well.
-//
-// Additionally, there's no way for us to link dynamic libraries, so we warn
-// about all dynamic library dependencies that they're not linked in.
-//
-// There's no need to include metadata in a static archive, so ensure to not
-// link in the metadata object file (and also don't prepare the archive with a
-// metadata file).
-fn link_staticlib(sess: &Session,
-                  codegen_results: &CodegenResults,
-                  out_filename: &Path,
-                  tempdir: &TempDir) {
-    let mut ab = link_rlib(sess,
-                           codegen_results,
-                           RlibFlavor::StaticlibBase,
-                           out_filename,
-                           tempdir);
-    let mut all_native_libs = vec![];
-
-    let res = each_linked_rlib(sess, &codegen_results.crate_info, &mut |cnum, path| {
-        let name = &codegen_results.crate_info.crate_name[&cnum];
-        let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
-
-        // Here when we include the rlib into our staticlib we need to make a
-        // decision whether to include the extra object files along the way.
-        // These extra object files come from statically included native
-        // libraries, but they may be cfg'd away with #[link(cfg(..))].
-        //
-        // This unstable feature, though, only needs liblibc to work. The only
-        // use case there is where musl is statically included in liblibc.rlib,
-        // so if we don't want the included version we just need to skip it. As
-        // a result the logic here is that if *any* linked library is cfg'd away
-        // we just skip all object files.
-        //
-        // Clearly this is not sufficient for a general purpose feature, and
-        // we'd want to read from the library's metadata to determine which
-        // object files come from where and selectively skip them.
-        let skip_object_files = native_libs.iter().any(|lib| {
-            lib.kind == NativeLibraryKind::NativeStatic && !relevant_lib(sess, lib)
-        });
-        ab.add_rlib(path,
-                    &name.as_str(),
-                    are_upstream_rust_objects_already_included(sess) &&
-                        !ignored_for_lto(sess, &codegen_results.crate_info, cnum),
-                    skip_object_files).unwrap();
-
-        all_native_libs.extend(codegen_results.crate_info.native_libraries[&cnum].iter().cloned());
-    });
-    if let Err(e) = res {
-        sess.fatal(&e);
-    }
-
-    ab.update_symbols();
-    ab.build();
-
-    if !all_native_libs.is_empty() {
-        if sess.opts.prints.contains(&PrintRequest::NativeStaticLibs) {
-            print_native_static_libs(sess, &all_native_libs);
-        }
-    }
-}
-
-fn print_native_static_libs(sess: &Session, all_native_libs: &[NativeLibrary]) {
-    let lib_args: Vec<_> = all_native_libs.iter()
-        .filter(|l| relevant_lib(sess, l))
-        .filter_map(|lib| {
-            let name = lib.name?;
-            match lib.kind {
-                NativeLibraryKind::NativeStaticNobundle |
-                NativeLibraryKind::NativeUnknown => {
-                    if sess.target.target.options.is_like_msvc {
-                        Some(format!("{}.lib", name))
-                    } else {
-                        Some(format!("-l{}", name))
-                    }
-                },
-                NativeLibraryKind::NativeFramework => {
-                    // ld-only syntax, since there are no frameworks in MSVC
-                    Some(format!("-framework {}", name))
-                },
-                // These are included, no need to print them
-                NativeLibraryKind::NativeStatic => None,
-            }
-        })
-        .collect();
-    if !lib_args.is_empty() {
-        sess.note_without_error("Link against the following native artifacts when linking \
-                                 against this static library. The order and any duplication \
-                                 can be significant on some platforms.");
-        // Prefix for greppability
-        sess.note_without_error(&format!("native-static-libs: {}", &lib_args.join(" ")));
-    }
-}
-
-fn get_file_path(sess: &Session, name: &str) -> PathBuf {
-    let fs = sess.target_filesearch(PathKind::Native);
-    let file_path = fs.get_lib_path().join(name);
-    if file_path.exists() {
-        return file_path
-    }
-    for search_path in fs.search_paths() {
-        let file_path = search_path.dir.join(name);
-        if file_path.exists() {
-            return file_path
-        }
-    }
-    PathBuf::from(name)
-}
-
-// Create a dynamic library or executable
-//
-// This will invoke the system linker/cc to create the resulting file. This
-// links to all upstream files as well.
-fn link_natively(sess: &Session,
-                 crate_type: config::CrateType,
-                 out_filename: &Path,
-                 codegen_results: &CodegenResults,
-                 tmpdir: &Path) {
-    info!("preparing {:?} to {:?}", crate_type, out_filename);
-    let (linker, flavor) = linker_and_flavor(sess);
-
-    // The invocations of cc share some flags across platforms
-    let (pname, mut cmd) = get_linker(sess, &linker, flavor);
-
-    if let Some(args) = sess.target.target.options.pre_link_args.get(&flavor) {
-        cmd.args(args);
-    }
-    if let Some(args) = sess.target.target.options.pre_link_args_crt.get(&flavor) {
-        if sess.crt_static() {
-            cmd.args(args);
-        }
-    }
-    if let Some(ref args) = sess.opts.debugging_opts.pre_link_args {
-        cmd.args(args);
-    }
-    cmd.args(&sess.opts.debugging_opts.pre_link_arg);
-
-    if sess.target.target.options.is_like_fuchsia {
-        let prefix = match sess.opts.debugging_opts.sanitizer {
-            Some(Sanitizer::Address) => "asan/",
-            _ => "",
-        };
-        cmd.arg(format!("--dynamic-linker={}ld.so.1", prefix));
-    }
-
-    let pre_link_objects = if crate_type == config::CrateType::Executable {
-        &sess.target.target.options.pre_link_objects_exe
-    } else {
-        &sess.target.target.options.pre_link_objects_dll
-    };
-    for obj in pre_link_objects {
-        cmd.arg(get_file_path(sess, obj));
-    }
-
-    if crate_type == config::CrateType::Executable && sess.crt_static() {
-        for obj in &sess.target.target.options.pre_link_objects_exe_crt {
-            cmd.arg(get_file_path(sess, obj));
-        }
-    }
-
-    if sess.target.target.options.is_like_emscripten {
-        cmd.arg("-s");
-        cmd.arg(if sess.panic_strategy() == PanicStrategy::Abort {
-            "DISABLE_EXCEPTION_CATCHING=1"
-        } else {
-            "DISABLE_EXCEPTION_CATCHING=0"
-        });
-    }
-
-    {
-        let target_cpu = crate::llvm_util::target_cpu(sess);
-        let mut linker = codegen_results.linker_info.to_linker(cmd, &sess, flavor, target_cpu);
-        link_args(&mut *linker, flavor, sess, crate_type, tmpdir,
-                  out_filename, codegen_results);
-        cmd = linker.finalize();
-    }
-    if let Some(args) = sess.target.target.options.late_link_args.get(&flavor) {
-        cmd.args(args);
-    }
-    for obj in &sess.target.target.options.post_link_objects {
-        cmd.arg(get_file_path(sess, obj));
-    }
-    if sess.crt_static() {
-        for obj in &sess.target.target.options.post_link_objects_crt {
-            cmd.arg(get_file_path(sess, obj));
-        }
-    }
-    if let Some(args) = sess.target.target.options.post_link_args.get(&flavor) {
-        cmd.args(args);
-    }
-    for &(ref k, ref v) in &sess.target.target.options.link_env {
-        cmd.env(k, v);
-    }
-
-    if sess.opts.debugging_opts.print_link_args {
-        println!("{:?}", &cmd);
-    }
-
-    // May have not found libraries in the right formats.
-    sess.abort_if_errors();
-
-    // Invoke the system linker
-    //
-    // Note that there's a terribly awful hack that really shouldn't be present
-    // in any compiler. Here an environment variable is supported to
-    // automatically retry the linker invocation if the linker looks like it
-    // segfaulted.
-    //
-    // Gee that seems odd, normally segfaults are things we want to know about!
-    // Unfortunately though in rust-lang/rust#38878 we're experiencing the
-    // linker segfaulting on Travis quite a bit which is causing quite a bit of
-    // pain to land PRs when they spuriously fail due to a segfault.
-    //
-    // The issue #38878 has some more debugging information on it as well, but
-    // this unfortunately looks like it's just a race condition in macOS's linker
-    // with some thread pool working in the background. It seems that no one
-    // currently knows a fix for this so in the meantime we're left with this...
-    info!("{:?}", &cmd);
-    let retry_on_segfault = env::var("RUSTC_RETRY_LINKER_ON_SEGFAULT").is_ok();
-    let mut prog;
-    let mut i = 0;
-    loop {
-        i += 1;
-        prog = time(sess, "running linker", || {
-            exec_linker(sess, &mut cmd, out_filename, tmpdir)
-        });
-        let output = match prog {
-            Ok(ref output) => output,
-            Err(_) => break,
-        };
-        if output.status.success() {
-            break
-        }
-        let mut out = output.stderr.clone();
-        out.extend(&output.stdout);
-        let out = String::from_utf8_lossy(&out);
-
-        // Check to see if the link failed with "unrecognized command line option:
-        // '-no-pie'" for gcc or "unknown argument: '-no-pie'" for clang. If so,
-        // reperform the link step without the -no-pie option. This is safe because
-        // if the linker doesn't support -no-pie then it should not default to
-        // linking executables as pie. Different versions of gcc seem to use
-        // different quotes in the error message so don't check for them.
-        if sess.target.target.options.linker_is_gnu &&
-           flavor != LinkerFlavor::Ld &&
-           (out.contains("unrecognized command line option") ||
-            out.contains("unknown argument")) &&
-           out.contains("-no-pie") &&
-           cmd.get_args().iter().any(|e| e.to_string_lossy() == "-no-pie") {
-            info!("linker output: {:?}", out);
-            warn!("Linker does not support -no-pie command line option. Retrying without.");
-            for arg in cmd.take_args() {
-                if arg.to_string_lossy() != "-no-pie" {
-                    cmd.arg(arg);
-                }
-            }
-            info!("{:?}", &cmd);
-            continue;
-        }
-        if !retry_on_segfault || i > 3 {
-            break
-        }
-        let msg_segv = "clang: error: unable to execute command: Segmentation fault: 11";
-        let msg_bus  = "clang: error: unable to execute command: Bus error: 10";
-        if !(out.contains(msg_segv) || out.contains(msg_bus)) {
-            break
-        }
-
-        warn!(
-            "looks like the linker segfaulted when we tried to call it, \
-             automatically retrying again. cmd = {:?}, out = {}.",
-            cmd,
-            out,
-        );
-    }
-
-    match prog {
-        Ok(prog) => {
-            fn escape_string(s: &[u8]) -> String {
-                str::from_utf8(s).map(|s| s.to_owned())
-                    .unwrap_or_else(|_| {
-                        let mut x = "Non-UTF-8 output: ".to_string();
-                        x.extend(s.iter()
-                                  .flat_map(|&b| ascii::escape_default(b))
-                                  .map(char::from));
-                        x
-                    })
-            }
-            if !prog.status.success() {
-                let mut output = prog.stderr.clone();
-                output.extend_from_slice(&prog.stdout);
-                sess.struct_err(&format!("linking with `{}` failed: {}",
-                                         pname.display(),
-                                         prog.status))
-                    .note(&format!("{:?}", &cmd))
-                    .note(&escape_string(&output))
-                    .emit();
-                sess.abort_if_errors();
-            }
-            info!("linker stderr:\n{}", escape_string(&prog.stderr));
-            info!("linker stdout:\n{}", escape_string(&prog.stdout));
-        },
-        Err(e) => {
-            let linker_not_found = e.kind() == io::ErrorKind::NotFound;
-
-            let mut linker_error = {
-                if linker_not_found {
-                    sess.struct_err(&format!("linker `{}` not found", pname.display()))
-                } else {
-                    sess.struct_err(&format!("could not exec the linker `{}`", pname.display()))
-                }
-            };
-
-            linker_error.note(&e.to_string());
-
-            if !linker_not_found {
-                linker_error.note(&format!("{:?}", &cmd));
-            }
-
-            linker_error.emit();
-
-            if sess.target.target.options.is_like_msvc && linker_not_found {
-                sess.note_without_error("the msvc targets depend on the msvc linker \
-                    but `link.exe` was not found");
-                sess.note_without_error("please ensure that VS 2013, VS 2015 or VS 2017 \
-                    was installed with the Visual C++ option");
-            }
-            sess.abort_if_errors();
-        }
-    }
-
-
-    // On macOS, debuggers need this utility to get run to do some munging of
-    // the symbols. Note, though, that if the object files are being preserved
-    // for their debug information there's no need for us to run dsymutil.
-    if sess.target.target.options.is_like_osx &&
-        sess.opts.debuginfo != DebugInfo::None &&
-        !preserve_objects_for_their_debuginfo(sess)
-    {
-        if let Err(e) = Command::new("dsymutil").arg(out_filename).output() {
-            sess.fatal(&format!("failed to run dsymutil: {}", e))
-        }
-    }
-
-    if sess.opts.target_triple.triple() == "wasm32-unknown-unknown" {
-        wasm::add_producer_section(
-            &out_filename,
-            &sess.edition().to_string(),
-            option_env!("CFG_VERSION").unwrap_or("unknown"),
-        );
-    }
-}
-
-fn exec_linker(sess: &Session, cmd: &mut Command, out_filename: &Path, tmpdir: &Path)
-    -> io::Result<Output>
-{
-    // When attempting to spawn the linker we run a risk of blowing out the
-    // size limits for spawning a new process with respect to the arguments
-    // we pass on the command line.
-    //
-    // Here we attempt to handle errors from the OS saying "your list of
-    // arguments is too big" by reinvoking the linker again with an `@`-file
-    // that contains all the arguments. The theory is that this is then
-    // accepted on all linkers and the linker will read all its options out of
-    // there instead of looking at the command line.
-    if !cmd.very_likely_to_exceed_some_spawn_limit() {
-        match cmd.command().stdout(Stdio::piped()).stderr(Stdio::piped()).spawn() {
-            Ok(child) => {
-                let output = child.wait_with_output();
-                flush_linked_file(&output, out_filename)?;
-                return output;
-            }
-            Err(ref e) if command_line_too_big(e) => {
-                info!("command line to linker was too big: {}", e);
-            }
-            Err(e) => return Err(e)
-        }
-    }
-
-    info!("falling back to passing arguments to linker via an @-file");
-    let mut cmd2 = cmd.clone();
-    let mut args = String::new();
-    for arg in cmd2.take_args() {
-        args.push_str(&Escape {
-            arg: arg.to_str().unwrap(),
-            is_like_msvc: sess.target.target.options.is_like_msvc,
-        }.to_string());
-        args.push_str("\n");
-    }
-    let file = tmpdir.join("linker-arguments");
-    let bytes = if sess.target.target.options.is_like_msvc {
-        let mut out = Vec::with_capacity((1 + args.len()) * 2);
-        // start the stream with a UTF-16 BOM
-        for c in iter::once(0xFEFF).chain(args.encode_utf16()) {
-            // encode in little endian
-            out.push(c as u8);
-            out.push((c >> 8) as u8);
-        }
-        out
-    } else {
-        args.into_bytes()
-    };
-    fs::write(&file, &bytes)?;
-    cmd2.arg(format!("@{}", file.display()));
-    info!("invoking linker {:?}", cmd2);
-    let output = cmd2.output();
-    flush_linked_file(&output, out_filename)?;
-    return output;
-
-    #[cfg(unix)]
-    fn flush_linked_file(_: &io::Result<Output>, _: &Path) -> io::Result<()> {
-        Ok(())
-    }
-
-    #[cfg(windows)]
-    fn flush_linked_file(command_output: &io::Result<Output>, out_filename: &Path)
-        -> io::Result<()>
-    {
-        // On Windows, under high I/O load, output buffers are sometimes not flushed,
-        // even long after process exit, causing nasty, non-reproducible output bugs.
-        //
-        // File::sync_all() calls FlushFileBuffers() down the line, which solves the problem.
-        //
-        // А full writeup of the original Chrome bug can be found at
-        // randomascii.wordpress.com/2018/02/25/compiler-bug-linker-bug-windows-kernel-bug/amp
-
-        if let &Ok(ref out) = command_output {
-            if out.status.success() {
-                if let Ok(of) = fs::OpenOptions::new().write(true).open(out_filename) {
-                    of.sync_all()?;
-                }
-            }
-        }
-
-        Ok(())
-    }
-
-    #[cfg(unix)]
-    fn command_line_too_big(err: &io::Error) -> bool {
-        err.raw_os_error() == Some(::libc::E2BIG)
-    }
-
-    #[cfg(windows)]
-    fn command_line_too_big(err: &io::Error) -> bool {
-        const ERROR_FILENAME_EXCED_RANGE: i32 = 206;
-        err.raw_os_error() == Some(ERROR_FILENAME_EXCED_RANGE)
-    }
-
-    struct Escape<'a> {
-        arg: &'a str,
-        is_like_msvc: bool,
-    }
-
-    impl<'a> fmt::Display for Escape<'a> {
-        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-            if self.is_like_msvc {
-                // This is "documented" at
-                // https://msdn.microsoft.com/en-us/library/4xdcbak7.aspx
-                //
-                // Unfortunately there's not a great specification of the
-                // syntax I could find online (at least) but some local
-                // testing showed that this seemed sufficient-ish to catch
-                // at least a few edge cases.
-                write!(f, "\"")?;
-                for c in self.arg.chars() {
-                    match c {
-                        '"' => write!(f, "\\{}", c)?,
-                        c => write!(f, "{}", c)?,
-                    }
-                }
-                write!(f, "\"")?;
-            } else {
-                // This is documented at https://linux.die.net/man/1/ld, namely:
-                //
-                // > Options in file are separated by whitespace. A whitespace
-                // > character may be included in an option by surrounding the
-                // > entire option in either single or double quotes. Any
-                // > character (including a backslash) may be included by
-                // > prefixing the character to be included with a backslash.
-                //
-                // We put an argument on each line, so all we need to do is
-                // ensure the line is interpreted as one whole argument.
-                for c in self.arg.chars() {
-                    match c {
-                        '\\' | ' ' => write!(f, "\\{}", c)?,
-                        c => write!(f, "{}", c)?,
-                    }
-                }
-            }
-            Ok(())
-        }
-    }
-}
-
-fn link_args(cmd: &mut dyn Linker,
-             flavor: LinkerFlavor,
-             sess: &Session,
-             crate_type: config::CrateType,
-             tmpdir: &Path,
-             out_filename: &Path,
-             codegen_results: &CodegenResults) {
-
-    // Linker plugins should be specified early in the list of arguments
-    cmd.linker_plugin_lto();
-
-    // The default library location, we need this to find the runtime.
-    // The location of crates will be determined as needed.
-    let lib_path = sess.target_filesearch(PathKind::All).get_lib_path();
-
-    // target descriptor
-    let t = &sess.target.target;
-
-    cmd.include_path(&fix_windows_verbatim_for_gcc(&lib_path));
-    for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
-        cmd.add_object(obj);
-    }
-    cmd.output_filename(out_filename);
-
-    if crate_type == config::CrateType::Executable &&
-       sess.target.target.options.is_like_windows {
-        if let Some(ref s) = codegen_results.windows_subsystem {
-            cmd.subsystem(s);
-        }
-    }
-
-    // If we're building a dynamic library then some platforms need to make sure
-    // that all symbols are exported correctly from the dynamic library.
-    if crate_type != config::CrateType::Executable ||
-       sess.target.target.options.is_like_emscripten {
-        cmd.export_symbols(tmpdir, crate_type);
-    }
-
-    // When linking a dynamic library, we put the metadata into a section of the
-    // executable. This metadata is in a separate object file from the main
-    // object file, so we link that in here.
-    if crate_type == config::CrateType::Dylib ||
-       crate_type == config::CrateType::ProcMacro {
-        if let Some(obj) = codegen_results.metadata_module.object.as_ref() {
-            cmd.add_object(obj);
-        }
-    }
-
-    let obj = codegen_results.allocator_module
-        .as_ref()
-        .and_then(|m| m.object.as_ref());
-    if let Some(obj) = obj {
-        cmd.add_object(obj);
-    }
-
-    // Try to strip as much out of the generated object by removing unused
-    // sections if possible. See more comments in linker.rs
-    if !sess.opts.cg.link_dead_code {
-        let keep_metadata = crate_type == config::CrateType::Dylib;
-        cmd.gc_sections(keep_metadata);
-    }
-
-    let used_link_args = &codegen_results.crate_info.link_args;
-
-    if crate_type == config::CrateType::Executable {
-        let mut position_independent_executable = false;
-
-        if t.options.position_independent_executables {
-            let empty_vec = Vec::new();
-            let args = sess.opts.cg.link_args.as_ref().unwrap_or(&empty_vec);
-            let more_args = &sess.opts.cg.link_arg;
-            let mut args = args.iter().chain(more_args.iter()).chain(used_link_args.iter());
-
-            if get_reloc_model(sess) == llvm::RelocMode::PIC
-                && !sess.crt_static() && !args.any(|x| *x == "-static") {
-                position_independent_executable = true;
-            }
-        }
-
-        if position_independent_executable {
-            cmd.position_independent_executable();
-        } else {
-            // recent versions of gcc can be configured to generate position
-            // independent executables by default. We have to pass -no-pie to
-            // explicitly turn that off. Not applicable to ld.
-            if sess.target.target.options.linker_is_gnu
-                && flavor != LinkerFlavor::Ld {
-                cmd.no_position_independent_executable();
-            }
-        }
-    }
-
-    let relro_level = match sess.opts.debugging_opts.relro_level {
-        Some(level) => level,
-        None => t.options.relro_level,
-    };
-    match relro_level {
-        RelroLevel::Full => {
-            cmd.full_relro();
-        },
-        RelroLevel::Partial => {
-            cmd.partial_relro();
-        },
-        RelroLevel::Off => {
-            cmd.no_relro();
-        },
-        RelroLevel::None => {
-        },
-    }
-
-    // Pass optimization flags down to the linker.
-    cmd.optimize();
-
-    // Pass debuginfo flags down to the linker.
-    cmd.debuginfo();
-
-    // We want to, by default, prevent the compiler from accidentally leaking in
-    // any system libraries, so we may explicitly ask linkers to not link to any
-    // libraries by default. Note that this does not happen for windows because
-    // windows pulls in some large number of libraries and I couldn't quite
-    // figure out which subset we wanted.
-    //
-    // This is all naturally configurable via the standard methods as well.
-    if !sess.opts.cg.default_linker_libraries.unwrap_or(false) &&
-        t.options.no_default_libraries
-    {
-        cmd.no_default_libraries();
-    }
-
-    // Take careful note of the ordering of the arguments we pass to the linker
-    // here. Linkers will assume that things on the left depend on things to the
-    // right. Things on the right cannot depend on things on the left. This is
-    // all formally implemented in terms of resolving symbols (libs on the right
-    // resolve unknown symbols of libs on the left, but not vice versa).
-    //
-    // For this reason, we have organized the arguments we pass to the linker as
-    // such:
-    //
-    //  1. The local object that LLVM just generated
-    //  2. Local native libraries
-    //  3. Upstream rust libraries
-    //  4. Upstream native libraries
-    //
-    // The rationale behind this ordering is that those items lower down in the
-    // list can't depend on items higher up in the list. For example nothing can
-    // depend on what we just generated (e.g., that'd be a circular dependency).
-    // Upstream rust libraries are not allowed to depend on our local native
-    // libraries as that would violate the structure of the DAG, in that
-    // scenario they are required to link to them as well in a shared fashion.
-    //
-    // Note that upstream rust libraries may contain native dependencies as
-    // well, but they also can't depend on what we just started to add to the
-    // link line. And finally upstream native libraries can't depend on anything
-    // in this DAG so far because they're only dylibs and dylibs can only depend
-    // on other dylibs (e.g., other native deps).
-    add_local_native_libraries(cmd, sess, codegen_results);
-    add_upstream_rust_crates(cmd, sess, codegen_results, crate_type, tmpdir);
-    add_upstream_native_libraries(cmd, sess, codegen_results, crate_type);
-
-    // Tell the linker what we're doing.
-    if crate_type != config::CrateType::Executable {
-        cmd.build_dylib(out_filename);
-    }
-    if crate_type == config::CrateType::Executable && sess.crt_static() {
-        cmd.build_static_executable();
-    }
-
-    if sess.opts.debugging_opts.pgo_gen.enabled() {
-        cmd.pgo_gen();
-    }
-
-    // FIXME (#2397): At some point we want to rpath our guesses as to
-    // where extern libraries might live, based on the
-    // addl_lib_search_paths
-    if sess.opts.cg.rpath {
-        let target_triple = sess.opts.target_triple.triple();
-        let mut get_install_prefix_lib_path = || {
-            let install_prefix = option_env!("CFG_PREFIX").expect("CFG_PREFIX");
-            let tlib = filesearch::relative_target_lib_path(&sess.sysroot, target_triple);
-            let mut path = PathBuf::from(install_prefix);
-            path.push(&tlib);
-
-            path
-        };
-        let mut rpath_config = RPathConfig {
-            used_crates: &codegen_results.crate_info.used_crates_dynamic,
-            out_filename: out_filename.to_path_buf(),
-            has_rpath: sess.target.target.options.has_rpath,
-            is_like_osx: sess.target.target.options.is_like_osx,
-            linker_is_gnu: sess.target.target.options.linker_is_gnu,
-            get_install_prefix_lib_path: &mut get_install_prefix_lib_path,
-        };
-        cmd.args(&rpath::get_rpath_flags(&mut rpath_config));
-    }
-
-    // Finally add all the linker arguments provided on the command line along
-    // with any #[link_args] attributes found inside the crate
-    if let Some(ref args) = sess.opts.cg.link_args {
-        cmd.args(args);
-    }
-    cmd.args(&sess.opts.cg.link_arg);
-    cmd.args(&used_link_args);
-}
-
-// # Native library linking
-//
-// User-supplied library search paths (-L on the command line). These are
-// the same paths used to find Rust crates, so some of them may have been
-// added already by the previous crate linking code. This only allows them
-// 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.
-//
-// Also note that the native libraries linked here are only the ones located
-// in the current crate. Upstream crates with native library dependencies
-// may have their native library pulled in above.
-fn add_local_native_libraries(cmd: &mut dyn Linker,
-                              sess: &Session,
-                              codegen_results: &CodegenResults) {
-    let filesearch = sess.target_filesearch(PathKind::All);
-    for search_path in filesearch.search_paths() {
-        match search_path.kind {
-            PathKind::Framework => { cmd.framework_path(&search_path.dir); }
-            _ => { cmd.include_path(&fix_windows_verbatim_for_gcc(&search_path.dir)); }
-        }
-    }
-
-    let relevant_libs = codegen_results.crate_info.used_libraries.iter().filter(|l| {
-        relevant_lib(sess, l)
-    });
-
-    let search_path = archive_search_paths(sess);
-    for lib in relevant_libs {
-        let name = match lib.name {
-            Some(ref l) => l,
-            None => continue,
-        };
-        match lib.kind {
-            NativeLibraryKind::NativeUnknown => cmd.link_dylib(&name.as_str()),
-            NativeLibraryKind::NativeFramework => cmd.link_framework(&name.as_str()),
-            NativeLibraryKind::NativeStaticNobundle => cmd.link_staticlib(&name.as_str()),
-            NativeLibraryKind::NativeStatic => cmd.link_whole_staticlib(&name.as_str(),
-                                                                        &search_path)
-        }
-    }
-}
-
-// # Rust Crate linking
-//
-// Rust crates are not considered at all when creating an rlib output. All
-// dependencies will be linked when producing the final output (instead of
-// the intermediate rlib version)
-fn add_upstream_rust_crates(cmd: &mut dyn Linker,
-                            sess: &Session,
-                            codegen_results: &CodegenResults,
-                            crate_type: config::CrateType,
-                            tmpdir: &Path) {
-    // All of the heavy lifting has previously been accomplished by the
-    // dependency_format module of the compiler. This is just crawling the
-    // output of that module, adding crates as necessary.
-    //
-    // Linking to a rlib involves just passing it to the linker (the linker
-    // will slurp up the object files inside), and linking to a dynamic library
-    // involves just passing the right -l flag.
-
-    let formats = sess.dependency_formats.borrow();
-    let data = formats.get(&crate_type).unwrap();
-
-    // Invoke get_used_crates to ensure that we get a topological sorting of
-    // crates.
-    let deps = &codegen_results.crate_info.used_crates_dynamic;
-
-    // There's a few internal crates in the standard library (aka libcore and
-    // libstd) which actually have a circular dependence upon one another. This
-    // currently arises through "weak lang items" where libcore requires things
-    // like `rust_begin_unwind` but libstd ends up defining it. To get this
-    // circular dependence to work correctly in all situations we'll need to be
-    // sure to correctly apply the `--start-group` and `--end-group` options to
-    // GNU linkers, otherwise if we don't use any other symbol from the standard
-    // library it'll get discarded and the whole application won't link.
-    //
-    // In this loop we're calculating the `group_end`, after which crate to
-    // pass `--end-group` and `group_start`, before which crate to pass
-    // `--start-group`. We currently do this by passing `--end-group` after
-    // the first crate (when iterating backwards) that requires a lang item
-    // defined somewhere else. Once that's set then when we've defined all the
-    // necessary lang items we'll pass `--start-group`.
-    //
-    // Note that this isn't amazing logic for now but it should do the trick
-    // for the current implementation of the standard library.
-    let mut group_end = None;
-    let mut group_start = None;
-    let mut end_with = FxHashSet::default();
-    let info = &codegen_results.crate_info;
-    for &(cnum, _) in deps.iter().rev() {
-        if let Some(missing) = info.missing_lang_items.get(&cnum) {
-            end_with.extend(missing.iter().cloned());
-            if end_with.len() > 0 && group_end.is_none() {
-                group_end = Some(cnum);
-            }
-        }
-        end_with.retain(|item| info.lang_item_to_crate.get(item) != Some(&cnum));
-        if end_with.len() == 0 && group_end.is_some() {
-            group_start = Some(cnum);
-            break
-        }
-    }
-
-    // If we didn't end up filling in all lang items from upstream crates then
-    // we'll be filling it in with our crate. This probably means we're the
-    // standard library itself, so skip this for now.
-    if group_end.is_some() && group_start.is_none() {
-        group_end = None;
-    }
-
-    let mut compiler_builtins = None;
-
-    for &(cnum, _) in deps.iter() {
-        if group_start == Some(cnum) {
-            cmd.group_start();
-        }
-
-        // We may not pass all crates through to the linker. Some crates may
-        // appear statically in an existing dylib, meaning we'll pick up all the
-        // symbols from the dylib.
-        let src = &codegen_results.crate_info.used_crate_source[&cnum];
-        match data[cnum.as_usize() - 1] {
-            _ if codegen_results.crate_info.profiler_runtime == Some(cnum) => {
-                add_static_crate(cmd, sess, codegen_results, tmpdir, crate_type, cnum);
-            }
-            _ if codegen_results.crate_info.sanitizer_runtime == Some(cnum) => {
-                link_sanitizer_runtime(cmd, sess, codegen_results, tmpdir, cnum);
-            }
-            // compiler-builtins are always placed last to ensure that they're
-            // linked correctly.
-            _ if codegen_results.crate_info.compiler_builtins == Some(cnum) => {
-                assert!(compiler_builtins.is_none());
-                compiler_builtins = Some(cnum);
-            }
-            Linkage::NotLinked |
-            Linkage::IncludedFromDylib => {}
-            Linkage::Static => {
-                add_static_crate(cmd, sess, codegen_results, tmpdir, crate_type, cnum);
-            }
-            Linkage::Dynamic => {
-                add_dynamic_crate(cmd, sess, &src.dylib.as_ref().unwrap().0)
-            }
-        }
-
-        if group_end == Some(cnum) {
-            cmd.group_end();
-        }
-    }
-
-    // compiler-builtins are always placed last to ensure that they're
-    // linked correctly.
-    // We must always link the `compiler_builtins` crate statically. Even if it
-    // was already "included" in a dylib (e.g., `libstd` when `-C prefer-dynamic`
-    // is used)
-    if let Some(cnum) = compiler_builtins {
-        add_static_crate(cmd, sess, codegen_results, tmpdir, crate_type, cnum);
-    }
-
-    // Converts a library file-stem into a cc -l argument
-    fn unlib<'a>(config: &config::Config, stem: &'a str) -> &'a str {
-        if stem.starts_with("lib") && !config.target.options.is_like_windows {
-            &stem[3..]
-        } else {
-            stem
-        }
-    }
-
-    // We must link the sanitizer runtime using -Wl,--whole-archive but since
-    // it's packed in a .rlib, it contains stuff that are not objects that will
-    // make the linker error. So we must remove those bits from the .rlib before
-    // linking it.
-    fn link_sanitizer_runtime(cmd: &mut dyn Linker,
-                              sess: &Session,
-                              codegen_results: &CodegenResults,
-                              tmpdir: &Path,
-                              cnum: CrateNum) {
-        let src = &codegen_results.crate_info.used_crate_source[&cnum];
-        let cratepath = &src.rlib.as_ref().unwrap().0;
-
-        if sess.target.target.options.is_like_osx {
-            // On Apple platforms, the sanitizer is always built as a dylib, and
-            // LLVM will link to `@rpath/*.dylib`, so we need to specify an
-            // rpath to the library as well (the rpath should be absolute, see
-            // PR #41352 for details).
-            //
-            // FIXME: Remove this logic into librustc_*san once Cargo supports it
-            let rpath = cratepath.parent().unwrap();
-            let rpath = rpath.to_str().expect("non-utf8 component in path");
-            cmd.args(&["-Wl,-rpath".into(), "-Xlinker".into(), rpath.into()]);
-        }
-
-        let dst = tmpdir.join(cratepath.file_name().unwrap());
-        let cfg = archive_config(sess, &dst, Some(cratepath));
-        let mut archive = ArchiveBuilder::new(cfg);
-        archive.update_symbols();
-
-        for f in archive.src_files() {
-            if f.ends_with(RLIB_BYTECODE_EXTENSION) || f == METADATA_FILENAME {
-                archive.remove_file(&f);
-            }
-        }
-
-        archive.build();
-
-        cmd.link_whole_rlib(&dst);
-    }
-
-    // Adds the static "rlib" versions of all crates to the command line.
-    // There's a bit of magic which happens here specifically related to LTO and
-    // dynamic libraries. Specifically:
-    //
-    // * For LTO, we remove upstream object files.
-    // * For dylibs we remove metadata and bytecode from upstream rlibs
-    //
-    // When performing LTO, almost(*) all of the bytecode from the upstream
-    // libraries has already been included in our object file output. As a
-    // result we need to remove the object files in the upstream libraries so
-    // the linker doesn't try to include them twice (or whine about duplicate
-    // symbols). We must continue to include the rest of the rlib, however, as
-    // it may contain static native libraries which must be linked in.
-    //
-    // (*) Crates marked with `#![no_builtins]` don't participate in LTO and
-    // their bytecode wasn't included. The object files in those libraries must
-    // still be passed to the linker.
-    //
-    // When making a dynamic library, linkers by default don't include any
-    // object files in an archive if they're not necessary to resolve the link.
-    // We basically want to convert the archive (rlib) to a dylib, though, so we
-    // *do* want everything included in the output, regardless of whether the
-    // linker thinks it's needed or not. As a result we must use the
-    // --whole-archive option (or the platform equivalent). When using this
-    // option the linker will fail if there are non-objects in the archive (such
-    // as our own metadata and/or bytecode). All in all, for rlibs to be
-    // entirely included in dylibs, we need to remove all non-object files.
-    //
-    // Note, however, that if we're not doing LTO or we're not producing a dylib
-    // (aka we're making an executable), we can just pass the rlib blindly to
-    // the linker (fast) because it's fine if it's not actually included as
-    // we're at the end of the dependency chain.
-    fn add_static_crate(cmd: &mut dyn Linker,
-                        sess: &Session,
-                        codegen_results: &CodegenResults,
-                        tmpdir: &Path,
-                        crate_type: config::CrateType,
-                        cnum: CrateNum) {
-        let src = &codegen_results.crate_info.used_crate_source[&cnum];
-        let cratepath = &src.rlib.as_ref().unwrap().0;
-
-        // See the comment above in `link_staticlib` and `link_rlib` for why if
-        // there's a static library that's not relevant we skip all object
-        // files.
-        let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
-        let skip_native = native_libs.iter().any(|lib| {
-            lib.kind == NativeLibraryKind::NativeStatic && !relevant_lib(sess, lib)
-        });
-
-        if (!are_upstream_rust_objects_already_included(sess) ||
-            ignored_for_lto(sess, &codegen_results.crate_info, cnum)) &&
-           crate_type != config::CrateType::Dylib &&
-           !skip_native {
-            cmd.link_rlib(&fix_windows_verbatim_for_gcc(cratepath));
-            return
-        }
-
-        let dst = tmpdir.join(cratepath.file_name().unwrap());
-        let name = cratepath.file_name().unwrap().to_str().unwrap();
-        let name = &name[3..name.len() - 5]; // chop off lib/.rlib
-
-        time_ext(sess.time_extended(), Some(sess), &format!("altering {}.rlib", name), || {
-            let cfg = archive_config(sess, &dst, Some(cratepath));
-            let mut archive = ArchiveBuilder::new(cfg);
-            archive.update_symbols();
-
-            let mut any_objects = false;
-            for f in archive.src_files() {
-                if f.ends_with(RLIB_BYTECODE_EXTENSION) || f == METADATA_FILENAME {
-                    archive.remove_file(&f);
-                    continue
-                }
-
-                let canonical = f.replace("-", "_");
-                let canonical_name = name.replace("-", "_");
-
-                // Look for `.rcgu.o` at the end of the filename to conclude
-                // that this is a Rust-related object file.
-                fn looks_like_rust(s: &str) -> bool {
-                    let path = Path::new(s);
-                    let ext = path.extension().and_then(|s| s.to_str());
-                    if ext != Some(OutputType::Object.extension()) {
-                        return false
-                    }
-                    let ext2 = path.file_stem()
-                        .and_then(|s| Path::new(s).extension())
-                        .and_then(|s| s.to_str());
-                    ext2 == Some(RUST_CGU_EXT)
-                }
-
-                let is_rust_object =
-                    canonical.starts_with(&canonical_name) &&
-                    looks_like_rust(&f);
-
-                // If we've been requested to skip all native object files
-                // (those not generated by the rust compiler) then we can skip
-                // this file. See above for why we may want to do this.
-                let skip_because_cfg_say_so = skip_native && !is_rust_object;
-
-                // If we're performing LTO and this is a rust-generated object
-                // file, then we don't need the object file as it's part of the
-                // LTO module. Note that `#![no_builtins]` is excluded from LTO,
-                // though, so we let that object file slide.
-                let skip_because_lto = are_upstream_rust_objects_already_included(sess) &&
-                    is_rust_object &&
-                    (sess.target.target.options.no_builtins ||
-                     !codegen_results.crate_info.is_no_builtins.contains(&cnum));
-
-                if skip_because_cfg_say_so || skip_because_lto {
-                    archive.remove_file(&f);
-                } else {
-                    any_objects = true;
-                }
-            }
-
-            if !any_objects {
-                return
-            }
-            archive.build();
-
-            // If we're creating a dylib, then we need to include the
-            // whole of each object in our archive into that artifact. This is
-            // because a `dylib` can be reused as an intermediate artifact.
-            //
-            // Note, though, that we don't want to include the whole of a
-            // compiler-builtins crate (e.g., compiler-rt) because it'll get
-            // repeatedly linked anyway.
-            if crate_type == config::CrateType::Dylib &&
-                codegen_results.crate_info.compiler_builtins != Some(cnum) {
-                cmd.link_whole_rlib(&fix_windows_verbatim_for_gcc(&dst));
-            } else {
-                cmd.link_rlib(&fix_windows_verbatim_for_gcc(&dst));
-            }
-        });
-    }
-
-    // Same thing as above, but for dynamic crates instead of static crates.
-    fn add_dynamic_crate(cmd: &mut dyn Linker, sess: &Session, cratepath: &Path) {
-        // Just need to tell the linker about where the library lives and
-        // what its name is
-        let parent = cratepath.parent();
-        if let Some(dir) = parent {
-            cmd.include_path(&fix_windows_verbatim_for_gcc(dir));
-        }
-        let filestem = cratepath.file_stem().unwrap().to_str().unwrap();
-        cmd.link_rust_dylib(&unlib(&sess.target, filestem),
-                            parent.unwrap_or(Path::new("")));
-    }
-}
-
-// Link in all of our upstream crates' native dependencies. Remember that
-// all of these upstream native dependencies are all non-static
-// dependencies. We've got two cases then:
-//
-// 1. The upstream crate is an rlib. In this case we *must* link in the
-// native dependency because the rlib is just an archive.
-//
-// 2. The upstream crate is a dylib. In order to use the dylib, we have to
-// have the dependency present on the system somewhere. Thus, we don't
-// gain a whole lot from not linking in the dynamic dependency to this
-// crate as well.
-//
-// The use case for this is a little subtle. In theory the native
-// dependencies of a crate are purely an implementation detail of the crate
-// itself, but the problem arises with generic and inlined functions. If a
-// generic function calls a native function, then the generic function must
-// be instantiated in the target crate, meaning that the native symbol must
-// also be resolved in the target crate.
-fn add_upstream_native_libraries(cmd: &mut dyn Linker,
-                                 sess: &Session,
-                                 codegen_results: &CodegenResults,
-                                 crate_type: config::CrateType) {
-    // Be sure to use a topological sorting of crates because there may be
-    // interdependencies between native libraries. When passing -nodefaultlibs,
-    // for example, almost all native libraries depend on libc, so we have to
-    // make sure that's all the way at the right (liblibc is near the base of
-    // the dependency chain).
-    //
-    // This passes RequireStatic, but the actual requirement doesn't matter,
-    // we're just getting an ordering of crate numbers, we're not worried about
-    // the paths.
-    let formats = sess.dependency_formats.borrow();
-    let data = formats.get(&crate_type).unwrap();
-
-    let crates = &codegen_results.crate_info.used_crates_static;
-    for &(cnum, _) in crates {
-        for lib in codegen_results.crate_info.native_libraries[&cnum].iter() {
-            let name = match lib.name {
-                Some(ref l) => l,
-                None => continue,
-            };
-            if !relevant_lib(sess, &lib) {
-                continue
-            }
-            match lib.kind {
-                NativeLibraryKind::NativeUnknown => cmd.link_dylib(&name.as_str()),
-                NativeLibraryKind::NativeFramework => cmd.link_framework(&name.as_str()),
-                NativeLibraryKind::NativeStaticNobundle => {
-                    // Link "static-nobundle" native libs only if the crate they originate from
-                    // is being linked statically to the current crate.  If it's linked dynamically
-                    // or is an rlib already included via some other dylib crate, the symbols from
-                    // native libs will have already been included in that dylib.
-                    if data[cnum.as_usize() - 1] == Linkage::Static {
-                        cmd.link_staticlib(&name.as_str())
-                    }
-                },
-                // ignore statically included native libraries here as we've
-                // already included them when we included the rust library
-                // previously
-                NativeLibraryKind::NativeStatic => {}
-            }
-        }
-    }
-}
-
-fn relevant_lib(sess: &Session, lib: &NativeLibrary) -> bool {
-    match lib.cfg {
-        Some(ref cfg) => attr::cfg_matches(cfg, &sess.parse_sess, None),
-        None => true,
-    }
-}
-
-fn are_upstream_rust_objects_already_included(sess: &Session) -> bool {
-    match sess.lto() {
-        Lto::Fat => true,
-        Lto::Thin => {
-            // If we defer LTO to the linker, we haven't run LTO ourselves, so
-            // any upstream object files have not been copied yet.
-            !sess.opts.cg.linker_plugin_lto.enabled()
-        }
-        Lto::No |
-        Lto::ThinLocal => false,
-    }
-}
diff --git a/src/librustc_codegen_llvm/back/lto.rs b/src/librustc_codegen_llvm/back/lto.rs
index 348f1a12126..74cda2d2fd1 100644
--- a/src/librustc_codegen_llvm/back/lto.rs
+++ b/src/librustc_codegen_llvm/back/lto.rs
@@ -1,4 +1,4 @@
-use crate::back::bytecode::{DecodedBytecode, RLIB_BYTECODE_EXTENSION};
+use crate::back::bytecode::DecodedBytecode;
 use crate::back::write::{self, DiagnosticHandlers, with_llvm_pmb, save_temp_bitcode,
     to_llvm_opt_settings};
 use crate::llvm::archive_ro::ArchiveRO;
@@ -16,7 +16,7 @@ use rustc::middle::exported_symbols::SymbolExportLevel;
 use rustc::session::config::{self, Lto};
 use rustc::util::common::time_ext;
 use rustc_data_structures::fx::FxHashMap;
-use rustc_codegen_ssa::{ModuleCodegen, ModuleKind};
+use rustc_codegen_ssa::{RLIB_BYTECODE_EXTENSION, ModuleCodegen, ModuleKind};
 
 use std::ffi::{CStr, CString};
 use std::ptr;
diff --git a/src/librustc_codegen_llvm/back/write.rs b/src/librustc_codegen_llvm/back/write.rs
index d803f10746e..cb59cf41a3c 100644
--- a/src/librustc_codegen_llvm/back/write.rs
+++ b/src/librustc_codegen_llvm/back/write.rs
@@ -1,5 +1,5 @@
 use crate::attributes;
-use crate::back::bytecode::{self, RLIB_BYTECODE_EXTENSION};
+use crate::back::bytecode;
 use crate::back::lto::ThinBuffer;
 use crate::base;
 use crate::consts;
@@ -16,7 +16,7 @@ use rustc_codegen_ssa::traits::*;
 use rustc::session::config::{self, OutputType, Passes, Lto, PgoGenerate};
 use rustc::session::Session;
 use rustc::ty::TyCtxt;
-use rustc_codegen_ssa::{ModuleCodegen, CompiledModule};
+use rustc_codegen_ssa::{RLIB_BYTECODE_EXTENSION, ModuleCodegen, CompiledModule};
 use rustc::util::common::time_ext;
 use rustc_fs_util::{path_to_c_string, link_or_copy};
 use rustc_data_structures::small_c_str::SmallCStr;
diff --git a/src/librustc_codegen_llvm/debuginfo/metadata.rs b/src/librustc_codegen_llvm/debuginfo/metadata.rs
index 6560ed0a8e6..31348b99c5a 100644
--- a/src/librustc_codegen_llvm/debuginfo/metadata.rs
+++ b/src/librustc_codegen_llvm/debuginfo/metadata.rs
@@ -376,7 +376,7 @@ fn vec_slice_metadata(
 
     return_if_metadata_created_in_meantime!(cx, unique_type_id);
 
-    let slice_type_name = compute_debuginfo_type_name(cx, slice_ptr_type, true);
+    let slice_type_name = compute_debuginfo_type_name(cx.tcx, slice_ptr_type, true);
 
     let (pointer_size, pointer_align) = cx.size_and_align_of(data_ptr_type);
     let (usize_size, usize_align) = cx.size_and_align_of(cx.tcx.types.usize);
@@ -479,7 +479,7 @@ fn trait_pointer_metadata(
 
     let trait_object_type = trait_object_type.unwrap_or(trait_type);
     let trait_type_name =
-        compute_debuginfo_type_name(cx, trait_object_type, false);
+        compute_debuginfo_type_name(cx.tcx, trait_object_type, false);
 
     let file_metadata = unknown_file_metadata(cx);
 
@@ -866,7 +866,7 @@ fn foreign_type_metadata(
 ) -> &'ll DIType {
     debug!("foreign_type_metadata: {:?}", t);
 
-    let name = compute_debuginfo_type_name(cx, t, false);
+    let name = compute_debuginfo_type_name(cx.tcx, t, false);
     create_struct_stub(cx, t, &name, unique_type_id, NO_SCOPE_METADATA)
 }
 
@@ -876,7 +876,7 @@ fn pointer_type_metadata(
     pointee_type_metadata: &'ll DIType,
 ) -> &'ll DIType {
     let (pointer_size, pointer_align) = cx.size_and_align_of(pointer_type);
-    let name = compute_debuginfo_type_name(cx, pointer_type, false);
+    let name = compute_debuginfo_type_name(cx.tcx, pointer_type, false);
     let name = SmallCStr::new(&name);
     unsafe {
         llvm::LLVMRustDIBuilderCreatePointerType(
@@ -1072,7 +1072,7 @@ fn prepare_struct_metadata(
     unique_type_id: UniqueTypeId,
     span: Span,
 ) -> RecursiveTypeDescription<'ll, 'tcx> {
-    let struct_name = compute_debuginfo_type_name(cx, struct_type, false);
+    let struct_name = compute_debuginfo_type_name(cx.tcx, struct_type, false);
 
     let (struct_def_id, variant) = match struct_type.sty {
         ty::Adt(def, _) => (def.did, def.non_enum_variant()),
@@ -1138,7 +1138,7 @@ fn prepare_tuple_metadata(
     unique_type_id: UniqueTypeId,
     span: Span,
 ) -> RecursiveTypeDescription<'ll, 'tcx> {
-    let tuple_name = compute_debuginfo_type_name(cx, tuple_type, false);
+    let tuple_name = compute_debuginfo_type_name(cx.tcx, tuple_type, false);
 
     let struct_stub = create_struct_stub(cx,
                                          tuple_type,
@@ -1194,7 +1194,7 @@ fn prepare_union_metadata(
     unique_type_id: UniqueTypeId,
     span: Span,
 ) -> RecursiveTypeDescription<'ll, 'tcx> {
-    let union_name = compute_debuginfo_type_name(cx, union_type, false);
+    let union_name = compute_debuginfo_type_name(cx.tcx, union_type, false);
 
     let (union_def_id, variant) = match union_type.sty {
         ty::Adt(def, _) => (def.did, def.non_enum_variant()),
@@ -1607,7 +1607,7 @@ fn prepare_enum_metadata(
     unique_type_id: UniqueTypeId,
     span: Span,
 ) -> RecursiveTypeDescription<'ll, 'tcx> {
-    let enum_name = compute_debuginfo_type_name(cx, enum_type, false);
+    let enum_name = compute_debuginfo_type_name(cx.tcx, enum_type, false);
 
     let containing_scope = get_namespace_for_item(cx, enum_def_id);
     // FIXME: This should emit actual file metadata for the enum, but we
diff --git a/src/librustc_codegen_llvm/debuginfo/mod.rs b/src/librustc_codegen_llvm/debuginfo/mod.rs
index 57e4ac07d5e..ae498673c1d 100644
--- a/src/librustc_codegen_llvm/debuginfo/mod.rs
+++ b/src/librustc_codegen_llvm/debuginfo/mod.rs
@@ -29,7 +29,7 @@ use rustc::util::nodemap::{DefIdMap, FxHashMap, FxHashSet};
 use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_data_structures::indexed_vec::IndexVec;
 use rustc_codegen_ssa::debuginfo::{FunctionDebugContext, MirDebugScope, VariableAccess,
-    VariableKind, FunctionDebugContextData};
+    VariableKind, FunctionDebugContextData, type_names};
 
 use libc::c_uint;
 use std::cell::RefCell;
@@ -44,7 +44,6 @@ use rustc_codegen_ssa::traits::*;
 pub mod gdb;
 mod utils;
 mod namespace;
-mod type_names;
 pub mod metadata;
 mod create_scope_map;
 mod source_loc;
@@ -422,7 +421,7 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                 let actual_type =
                     cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), actual_type);
                 // Add actual type name to <...> clause of function name
-                let actual_type_name = compute_debuginfo_type_name(cx,
+                let actual_type_name = compute_debuginfo_type_name(cx.tcx(),
                                                                    actual_type,
                                                                    true);
                 name_to_append_suffix_to.push_str(&actual_type_name[..]);
diff --git a/src/librustc_codegen_llvm/lib.rs b/src/librustc_codegen_llvm/lib.rs
index c2eee59fbb0..cee0d5be647 100644
--- a/src/librustc_codegen_llvm/lib.rs
+++ b/src/librustc_codegen_llvm/lib.rs
@@ -44,8 +44,6 @@ extern crate rustc_fs_util;
 #[macro_use] extern crate syntax;
 extern crate syntax_pos;
 extern crate rustc_errors as errors;
-extern crate serialize;
-extern crate tempfile;
 
 use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::back::write::{CodegenContext, ModuleConfig, FatLTOInput};
@@ -73,13 +71,10 @@ use rustc_codegen_utils::codegen_backend::CodegenBackend;
 mod error_codes;
 
 mod back {
-    mod archive;
+    pub mod archive;
     pub mod bytecode;
-    pub mod link;
     pub mod lto;
     pub mod write;
-    mod rpath;
-    pub mod wasm;
 }
 
 mod abi;
@@ -331,8 +326,17 @@ impl CodegenBackend for LlvmCodegenBackend {
         // This should produce either a finished executable or library.
         sess.profiler(|p| p.start_activity("link_crate"));
         time(sess, "linking", || {
-            back::link::link_binary(sess, &codegen_results,
-                                    outputs, &codegen_results.crate_name.as_str());
+            use rustc_codegen_ssa::back::link::link_binary;
+            use crate::back::archive::LlvmArchiveBuilder;
+
+            let target_cpu = crate::llvm_util::target_cpu(sess);
+            link_binary::<LlvmArchiveBuilder<'_>>(
+                sess,
+                &codegen_results,
+                outputs,
+                &codegen_results.crate_name.as_str(),
+                target_cpu,
+            );
         });
         sess.profiler(|p| p.end_activity("link_crate"));
 
diff --git a/src/librustc_codegen_llvm/metadata.rs b/src/librustc_codegen_llvm/metadata.rs
index a2df687d58f..7cf497cb5d0 100644
--- a/src/librustc_codegen_llvm/metadata.rs
+++ b/src/librustc_codegen_llvm/metadata.rs
@@ -5,6 +5,8 @@ use rustc::middle::cstore::MetadataLoader;
 use rustc_target::spec::Target;
 
 use rustc_data_structures::owning_ref::OwningRef;
+use rustc_codegen_ssa::METADATA_FILENAME;
+
 use std::path::Path;
 use std::ptr;
 use std::slice;
@@ -12,8 +14,6 @@ use rustc_fs_util::path_to_c_string;
 
 pub use rustc_data_structures::sync::MetadataRef;
 
-pub const METADATA_FILENAME: &str = "rust.metadata.bin";
-
 pub struct LlvmMetadataLoader;
 
 impl MetadataLoader for LlvmMetadataLoader {
diff --git a/src/librustc_codegen_ssa/Cargo.toml b/src/librustc_codegen_ssa/Cargo.toml
index 4702e34aa19..af99d39182c 100644
--- a/src/librustc_codegen_ssa/Cargo.toml
+++ b/src/librustc_codegen_ssa/Cargo.toml
@@ -20,6 +20,7 @@ log = "0.4.5"
 libc = "0.2.44"
 jobserver = "0.1.11"
 parking_lot = "0.7"
+tempfile = "3.0.5"
 
 serialize = { path = "../libserialize" }
 syntax = { path = "../libsyntax" }
diff --git a/src/librustc_codegen_ssa/back/archive.rs b/src/librustc_codegen_ssa/back/archive.rs
index 0a16d1b03e2..23d580ef08b 100644
--- a/src/librustc_codegen_ssa/back/archive.rs
+++ b/src/librustc_codegen_ssa/back/archive.rs
@@ -1,6 +1,7 @@
 use rustc::session::Session;
 
-use std::path::PathBuf;
+use std::io;
+use std::path::{Path, PathBuf};
 
 pub fn find_library(name: &str, search_paths: &[PathBuf], sess: &Session)
                     -> PathBuf {
@@ -24,3 +25,23 @@ pub fn find_library(name: &str, search_paths: &[PathBuf], sess: &Session)
     sess.fatal(&format!("could not find native static library `{}`, \
                          perhaps an -L flag is missing?", name));
 }
+
+pub trait ArchiveBuilder<'a> {
+    fn new(sess: &'a Session, output: &Path, input: Option<&Path>) -> Self;
+
+    fn add_file(&mut self, path: &Path);
+    fn remove_file(&mut self, name: &str);
+    fn src_files(&mut self) -> Vec<String>;
+
+    fn add_rlib(
+        &mut self,
+        path: &Path,
+        name: &str,
+        lto: bool,
+        skip_objects: bool,
+    ) -> io::Result<()>;
+    fn add_native_library(&mut self, name: &str);
+    fn update_symbols(&mut self);
+
+    fn build(self);
+}
diff --git a/src/librustc_codegen_ssa/back/link.rs b/src/librustc_codegen_ssa/back/link.rs
index a0e2dcd646d..166234c83fc 100644
--- a/src/librustc_codegen_ssa/back/link.rs
+++ b/src/librustc_codegen_ssa/back/link.rs
@@ -1,21 +1,40 @@
 /// For all the linkers we support, and information they might
 /// need out of the shared crate context before we get rid of it.
 
-use rustc::session::{Session, config};
+use rustc::session::{Session, filesearch};
+use rustc::session::config::{
+    self, RUST_CGU_EXT, DebugInfo, OutputFilenames, OutputType, PrintRequest, Sanitizer
+};
 use rustc::session::search_paths::PathKind;
 use rustc::middle::dependency_format::Linkage;
-use rustc::middle::cstore::LibSource;
-use rustc_target::spec::LinkerFlavor;
+use rustc::middle::cstore::{LibSource, NativeLibrary, NativeLibraryKind};
+use rustc::util::common::{time, time_ext};
 use rustc::hir::def_id::CrateNum;
+use rustc_data_structures::fx::FxHashSet;
+use rustc_fs_util::fix_windows_verbatim_for_gcc;
+use rustc_target::spec::{PanicStrategy, RelroLevel, LinkerFlavor};
 
+use crate::{METADATA_FILENAME, RLIB_BYTECODE_EXTENSION, CrateInfo, CodegenResults};
+use super::archive::ArchiveBuilder;
 use super::command::Command;
-use crate::CrateInfo;
+use super::linker::Linker;
+use super::rpath::{self, RPathConfig};
 
 use cc::windows_registry;
+use tempfile::{Builder as TempFileBuilder, TempDir};
+
+use std::ascii;
+use std::char;
+use std::fmt;
 use std::fs;
+use std::io;
 use std::path::{Path, PathBuf};
+use std::process::{Output, Stdio};
+use std::str;
 use std::env;
 
+pub use rustc_codegen_utils::link::*;
+
 pub fn remove(sess: &Session, path: &Path) {
     if let Err(e) = fs::remove_file(path) {
         sess.err(&format!("failed to remove {}: {}",
@@ -24,6 +43,129 @@ pub fn remove(sess: &Session, path: &Path) {
     }
 }
 
+/// Performs the linkage portion of the compilation phase. This will generate all
+/// of the requested outputs for this compilation session.
+pub fn link_binary<'a, B: ArchiveBuilder<'a>>(sess: &'a Session,
+                          codegen_results: &CodegenResults,
+                          outputs: &OutputFilenames,
+                          crate_name: &str,
+                          target_cpu: &str) -> Vec<PathBuf> {
+    let mut out_filenames = Vec::new();
+    for &crate_type in sess.crate_types.borrow().iter() {
+        // Ignore executable crates if we have -Z no-codegen, as they will error.
+        let output_metadata = sess.opts.output_types.contains_key(&OutputType::Metadata);
+        if (sess.opts.debugging_opts.no_codegen || !sess.opts.output_types.should_codegen()) &&
+           !output_metadata &&
+           crate_type == config::CrateType::Executable {
+            continue;
+        }
+
+        if invalid_output_for_target(sess, crate_type) {
+           bug!("invalid output type `{:?}` for target os `{}`",
+                crate_type, sess.opts.target_triple);
+        }
+        let out_files = link_binary_output::<B>(sess,
+                                           codegen_results,
+                                           crate_type,
+                                           outputs,
+                                           crate_name,
+                                           target_cpu);
+        out_filenames.extend(out_files);
+    }
+
+    // Remove the temporary object file and metadata if we aren't saving temps
+    if !sess.opts.cg.save_temps {
+        if sess.opts.output_types.should_codegen() && !preserve_objects_for_their_debuginfo(sess) {
+            for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
+                remove(sess, obj);
+            }
+        }
+        for obj in codegen_results.modules.iter().filter_map(|m| m.bytecode_compressed.as_ref()) {
+            remove(sess, obj);
+        }
+        if let Some(ref obj) = codegen_results.metadata_module.object {
+            remove(sess, obj);
+        }
+        if let Some(ref allocator) = codegen_results.allocator_module {
+            if let Some(ref obj) = allocator.object {
+                remove(sess, obj);
+            }
+            if let Some(ref bc) = allocator.bytecode_compressed {
+                remove(sess, bc);
+            }
+        }
+    }
+
+    out_filenames
+}
+
+fn link_binary_output<'a, B: ArchiveBuilder<'a>>(sess: &'a Session,
+                      codegen_results: &CodegenResults,
+                      crate_type: config::CrateType,
+                      outputs: &OutputFilenames,
+                      crate_name: &str,
+                      target_cpu: &str) -> Vec<PathBuf> {
+    for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
+        check_file_is_writeable(obj, sess);
+    }
+
+    let mut out_filenames = vec![];
+
+    if outputs.outputs.contains_key(&OutputType::Metadata) {
+        let out_filename = filename_for_metadata(sess, crate_name, outputs);
+        // To avoid races with another rustc process scanning the output directory,
+        // we need to write the file somewhere else and atomically move it to its
+        // final destination, with a `fs::rename` call. In order for the rename to
+        // always succeed, the temporary file needs to be on the same filesystem,
+        // which is why we create it inside the output directory specifically.
+        let metadata_tmpdir = TempFileBuilder::new()
+            .prefix("rmeta")
+            .tempdir_in(out_filename.parent().unwrap())
+            .unwrap_or_else(|err| sess.fatal(&format!("couldn't create a temp dir: {}", err)));
+        let metadata = emit_metadata(sess, codegen_results, &metadata_tmpdir);
+        if let Err(e) = fs::rename(metadata, &out_filename) {
+            sess.fatal(&format!("failed to write {}: {}", out_filename.display(), e));
+        }
+        out_filenames.push(out_filename);
+    }
+
+    let tmpdir = TempFileBuilder::new().prefix("rustc").tempdir().unwrap_or_else(|err|
+        sess.fatal(&format!("couldn't create a temp dir: {}", err)));
+
+    if outputs.outputs.should_codegen() {
+        let out_filename = out_filename(sess, crate_type, outputs, crate_name);
+        match crate_type {
+            config::CrateType::Rlib => {
+                link_rlib::<B>(sess,
+                          codegen_results,
+                          RlibFlavor::Normal,
+                          &out_filename,
+                          &tmpdir).build();
+            }
+            config::CrateType::Staticlib => {
+                link_staticlib::<B>(sess, codegen_results, &out_filename, &tmpdir);
+            }
+            _ => {
+                link_natively::<B>(
+                    sess,
+                    crate_type,
+                    &out_filename,
+                    codegen_results,
+                    tmpdir.path(),
+                    target_cpu,
+                );
+            }
+        }
+        out_filenames.push(out_filename);
+    }
+
+    if sess.opts.cg.save_temps {
+        let _ = tmpdir.into_path();
+    }
+
+    out_filenames
+}
+
 // The third parameter is for env vars, used on windows to set up the
 // path for MSVC to find its DLLs, and gcc to find its bundled
 // toolchain
@@ -116,6 +258,444 @@ pub fn each_linked_rlib(sess: &Session,
     Ok(())
 }
 
+/// We use a temp directory here to avoid races between concurrent rustc processes,
+/// such as builds in the same directory using the same filename for metadata while
+/// building an `.rlib` (stomping over one another), or writing an `.rmeta` into a
+/// directory being searched for `extern crate` (observing an incomplete file).
+/// The returned path is the temporary file containing the complete metadata.
+fn emit_metadata<'a>(
+    sess: &'a Session,
+    codegen_results: &CodegenResults,
+    tmpdir: &TempDir
+) -> PathBuf {
+    let out_filename = tmpdir.path().join(METADATA_FILENAME);
+    let result = fs::write(&out_filename, &codegen_results.metadata.raw_data);
+
+    if let Err(e) = result {
+        sess.fatal(&format!("failed to write {}: {}", out_filename.display(), e));
+    }
+
+    out_filename
+}
+
+// Create an 'rlib'
+//
+// An rlib in its current incarnation is essentially a renamed .a file. The
+// rlib primarily contains the object file of the crate, but it also contains
+// all of the object files from native libraries. This is done by unzipping
+// native libraries and inserting all of the contents into this archive.
+fn link_rlib<'a, B: ArchiveBuilder<'a>>(sess: &'a Session,
+                 codegen_results: &CodegenResults,
+                 flavor: RlibFlavor,
+                 out_filename: &Path,
+                 tmpdir: &TempDir) -> B {
+    info!("preparing rlib to {:?}", out_filename);
+    let mut ab = <B as ArchiveBuilder>::new(sess, out_filename, None);
+
+    for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
+        ab.add_file(obj);
+    }
+
+    // Note that in this loop we are ignoring the value of `lib.cfg`. That is,
+    // we may not be configured to actually include a static library if we're
+    // adding it here. That's because later when we consume this rlib we'll
+    // decide whether we actually needed the static library or not.
+    //
+    // To do this "correctly" we'd need to keep track of which libraries added
+    // which object files to the archive. We don't do that here, however. The
+    // #[link(cfg(..))] feature is unstable, though, and only intended to get
+    // liblibc working. In that sense the check below just indicates that if
+    // there are any libraries we want to omit object files for at link time we
+    // just exclude all custom object files.
+    //
+    // Eventually if we want to stabilize or flesh out the #[link(cfg(..))]
+    // feature then we'll need to figure out how to record what objects were
+    // loaded from the libraries found here and then encode that into the
+    // metadata of the rlib we're generating somehow.
+    for lib in codegen_results.crate_info.used_libraries.iter() {
+        match lib.kind {
+            NativeLibraryKind::NativeStatic => {}
+            NativeLibraryKind::NativeStaticNobundle |
+            NativeLibraryKind::NativeFramework |
+            NativeLibraryKind::NativeUnknown => continue,
+        }
+        if let Some(name) = lib.name {
+            ab.add_native_library(&name.as_str());
+        }
+    }
+
+    // After adding all files to the archive, we need to update the
+    // symbol table of the archive.
+    ab.update_symbols();
+
+    // Note that it is important that we add all of our non-object "magical
+    // files" *after* all of the object files in the archive. The reason for
+    // this is as follows:
+    //
+    // * When performing LTO, this archive will be modified to remove
+    //   objects from above. The reason for this is described below.
+    //
+    // * When the system linker looks at an archive, it will attempt to
+    //   determine the architecture of the archive in order to see whether its
+    //   linkable.
+    //
+    //   The algorithm for this detection is: iterate over the files in the
+    //   archive. Skip magical SYMDEF names. Interpret the first file as an
+    //   object file. Read architecture from the object file.
+    //
+    // * As one can probably see, if "metadata" and "foo.bc" were placed
+    //   before all of the objects, then the architecture of this archive would
+    //   not be correctly inferred once 'foo.o' is removed.
+    //
+    // Basically, all this means is that this code should not move above the
+    // code above.
+    match flavor {
+        RlibFlavor::Normal => {
+            // Instead of putting the metadata in an object file section, rlibs
+            // contain the metadata in a separate file.
+            ab.add_file(&emit_metadata(sess, codegen_results, tmpdir));
+
+            // For LTO purposes, the bytecode of this library is also inserted
+            // into the archive.
+            for bytecode in codegen_results
+                .modules
+                .iter()
+                .filter_map(|m| m.bytecode_compressed.as_ref())
+            {
+                ab.add_file(bytecode);
+            }
+
+            // After adding all files to the archive, we need to update the
+            // symbol table of the archive. This currently dies on macOS (see
+            // #11162), and isn't necessary there anyway
+            if !sess.target.target.options.is_like_osx {
+                ab.update_symbols();
+            }
+        }
+
+        RlibFlavor::StaticlibBase => {
+            let obj = codegen_results.allocator_module
+                .as_ref()
+                .and_then(|m| m.object.as_ref());
+            if let Some(obj) = obj {
+                ab.add_file(obj);
+            }
+        }
+    }
+
+    ab
+}
+
+// Create a static archive
+//
+// This is essentially the same thing as an rlib, but it also involves adding
+// all of the upstream crates' objects into the archive. This will slurp in
+// all of the native libraries of upstream dependencies as well.
+//
+// Additionally, there's no way for us to link dynamic libraries, so we warn
+// about all dynamic library dependencies that they're not linked in.
+//
+// There's no need to include metadata in a static archive, so ensure to not
+// link in the metadata object file (and also don't prepare the archive with a
+// metadata file).
+fn link_staticlib<'a, B: ArchiveBuilder<'a>>(sess: &'a Session,
+                  codegen_results: &CodegenResults,
+                  out_filename: &Path,
+                  tempdir: &TempDir) {
+    let mut ab = link_rlib::<B>(sess,
+                           codegen_results,
+                           RlibFlavor::StaticlibBase,
+                           out_filename,
+                           tempdir);
+    let mut all_native_libs = vec![];
+
+    let res = each_linked_rlib(sess, &codegen_results.crate_info, &mut |cnum, path| {
+        let name = &codegen_results.crate_info.crate_name[&cnum];
+        let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
+
+        // Here when we include the rlib into our staticlib we need to make a
+        // decision whether to include the extra object files along the way.
+        // These extra object files come from statically included native
+        // libraries, but they may be cfg'd away with #[link(cfg(..))].
+        //
+        // This unstable feature, though, only needs liblibc to work. The only
+        // use case there is where musl is statically included in liblibc.rlib,
+        // so if we don't want the included version we just need to skip it. As
+        // a result the logic here is that if *any* linked library is cfg'd away
+        // we just skip all object files.
+        //
+        // Clearly this is not sufficient for a general purpose feature, and
+        // we'd want to read from the library's metadata to determine which
+        // object files come from where and selectively skip them.
+        let skip_object_files = native_libs.iter().any(|lib| {
+            lib.kind == NativeLibraryKind::NativeStatic && !relevant_lib(sess, lib)
+        });
+        ab.add_rlib(path,
+                    &name.as_str(),
+                    are_upstream_rust_objects_already_included(sess) &&
+                        !ignored_for_lto(sess, &codegen_results.crate_info, cnum),
+                    skip_object_files).unwrap();
+
+        all_native_libs.extend(codegen_results.crate_info.native_libraries[&cnum].iter().cloned());
+    });
+    if let Err(e) = res {
+        sess.fatal(&e);
+    }
+
+    ab.update_symbols();
+    ab.build();
+
+    if !all_native_libs.is_empty() {
+        if sess.opts.prints.contains(&PrintRequest::NativeStaticLibs) {
+            print_native_static_libs(sess, &all_native_libs);
+        }
+    }
+}
+
+// Create a dynamic library or executable
+//
+// This will invoke the system linker/cc to create the resulting file. This
+// links to all upstream files as well.
+fn link_natively<'a, B: ArchiveBuilder<'a>>(sess: &'a Session,
+                 crate_type: config::CrateType,
+                 out_filename: &Path,
+                 codegen_results: &CodegenResults,
+                 tmpdir: &Path,
+                 target_cpu: &str) {
+    info!("preparing {:?} to {:?}", crate_type, out_filename);
+    let (linker, flavor) = linker_and_flavor(sess);
+
+    // The invocations of cc share some flags across platforms
+    let (pname, mut cmd) = get_linker(sess, &linker, flavor);
+
+    if let Some(args) = sess.target.target.options.pre_link_args.get(&flavor) {
+        cmd.args(args);
+    }
+    if let Some(args) = sess.target.target.options.pre_link_args_crt.get(&flavor) {
+        if sess.crt_static() {
+            cmd.args(args);
+        }
+    }
+    if let Some(ref args) = sess.opts.debugging_opts.pre_link_args {
+        cmd.args(args);
+    }
+    cmd.args(&sess.opts.debugging_opts.pre_link_arg);
+
+    if sess.target.target.options.is_like_fuchsia {
+        let prefix = match sess.opts.debugging_opts.sanitizer {
+            Some(Sanitizer::Address) => "asan/",
+            _ => "",
+        };
+        cmd.arg(format!("--dynamic-linker={}ld.so.1", prefix));
+    }
+
+    let pre_link_objects = if crate_type == config::CrateType::Executable {
+        &sess.target.target.options.pre_link_objects_exe
+    } else {
+        &sess.target.target.options.pre_link_objects_dll
+    };
+    for obj in pre_link_objects {
+        cmd.arg(get_file_path(sess, obj));
+    }
+
+    if crate_type == config::CrateType::Executable && sess.crt_static() {
+        for obj in &sess.target.target.options.pre_link_objects_exe_crt {
+            cmd.arg(get_file_path(sess, obj));
+        }
+    }
+
+    if sess.target.target.options.is_like_emscripten {
+        cmd.arg("-s");
+        cmd.arg(if sess.panic_strategy() == PanicStrategy::Abort {
+            "DISABLE_EXCEPTION_CATCHING=1"
+        } else {
+            "DISABLE_EXCEPTION_CATCHING=0"
+        });
+    }
+
+    {
+        let mut linker = codegen_results.linker_info.to_linker(cmd, &sess, flavor, target_cpu);
+        link_args::<B>(&mut *linker, flavor, sess, crate_type, tmpdir,
+                  out_filename, codegen_results);
+        cmd = linker.finalize();
+    }
+    if let Some(args) = sess.target.target.options.late_link_args.get(&flavor) {
+        cmd.args(args);
+    }
+    for obj in &sess.target.target.options.post_link_objects {
+        cmd.arg(get_file_path(sess, obj));
+    }
+    if sess.crt_static() {
+        for obj in &sess.target.target.options.post_link_objects_crt {
+            cmd.arg(get_file_path(sess, obj));
+        }
+    }
+    if let Some(args) = sess.target.target.options.post_link_args.get(&flavor) {
+        cmd.args(args);
+    }
+    for &(ref k, ref v) in &sess.target.target.options.link_env {
+        cmd.env(k, v);
+    }
+
+    if sess.opts.debugging_opts.print_link_args {
+        println!("{:?}", &cmd);
+    }
+
+    // May have not found libraries in the right formats.
+    sess.abort_if_errors();
+
+    // Invoke the system linker
+    //
+    // Note that there's a terribly awful hack that really shouldn't be present
+    // in any compiler. Here an environment variable is supported to
+    // automatically retry the linker invocation if the linker looks like it
+    // segfaulted.
+    //
+    // Gee that seems odd, normally segfaults are things we want to know about!
+    // Unfortunately though in rust-lang/rust#38878 we're experiencing the
+    // linker segfaulting on Travis quite a bit which is causing quite a bit of
+    // pain to land PRs when they spuriously fail due to a segfault.
+    //
+    // The issue #38878 has some more debugging information on it as well, but
+    // this unfortunately looks like it's just a race condition in macOS's linker
+    // with some thread pool working in the background. It seems that no one
+    // currently knows a fix for this so in the meantime we're left with this...
+    info!("{:?}", &cmd);
+    let retry_on_segfault = env::var("RUSTC_RETRY_LINKER_ON_SEGFAULT").is_ok();
+    let mut prog;
+    let mut i = 0;
+    loop {
+        i += 1;
+        prog = time(sess, "running linker", || {
+            exec_linker(sess, &mut cmd, out_filename, tmpdir)
+        });
+        let output = match prog {
+            Ok(ref output) => output,
+            Err(_) => break,
+        };
+        if output.status.success() {
+            break
+        }
+        let mut out = output.stderr.clone();
+        out.extend(&output.stdout);
+        let out = String::from_utf8_lossy(&out);
+
+        // Check to see if the link failed with "unrecognized command line option:
+        // '-no-pie'" for gcc or "unknown argument: '-no-pie'" for clang. If so,
+        // reperform the link step without the -no-pie option. This is safe because
+        // if the linker doesn't support -no-pie then it should not default to
+        // linking executables as pie. Different versions of gcc seem to use
+        // different quotes in the error message so don't check for them.
+        if sess.target.target.options.linker_is_gnu &&
+           flavor != LinkerFlavor::Ld &&
+           (out.contains("unrecognized command line option") ||
+            out.contains("unknown argument")) &&
+           out.contains("-no-pie") &&
+           cmd.get_args().iter().any(|e| e.to_string_lossy() == "-no-pie") {
+            info!("linker output: {:?}", out);
+            warn!("Linker does not support -no-pie command line option. Retrying without.");
+            for arg in cmd.take_args() {
+                if arg.to_string_lossy() != "-no-pie" {
+                    cmd.arg(arg);
+                }
+            }
+            info!("{:?}", &cmd);
+            continue;
+        }
+        if !retry_on_segfault || i > 3 {
+            break
+        }
+        let msg_segv = "clang: error: unable to execute command: Segmentation fault: 11";
+        let msg_bus  = "clang: error: unable to execute command: Bus error: 10";
+        if !(out.contains(msg_segv) || out.contains(msg_bus)) {
+            break
+        }
+
+        warn!(
+            "looks like the linker segfaulted when we tried to call it, \
+             automatically retrying again. cmd = {:?}, out = {}.",
+            cmd,
+            out,
+        );
+    }
+
+    match prog {
+        Ok(prog) => {
+            fn escape_string(s: &[u8]) -> String {
+                str::from_utf8(s).map(|s| s.to_owned())
+                    .unwrap_or_else(|_| {
+                        let mut x = "Non-UTF-8 output: ".to_string();
+                        x.extend(s.iter()
+                                  .flat_map(|&b| ascii::escape_default(b))
+                                  .map(char::from));
+                        x
+                    })
+            }
+            if !prog.status.success() {
+                let mut output = prog.stderr.clone();
+                output.extend_from_slice(&prog.stdout);
+                sess.struct_err(&format!("linking with `{}` failed: {}",
+                                         pname.display(),
+                                         prog.status))
+                    .note(&format!("{:?}", &cmd))
+                    .note(&escape_string(&output))
+                    .emit();
+                sess.abort_if_errors();
+            }
+            info!("linker stderr:\n{}", escape_string(&prog.stderr));
+            info!("linker stdout:\n{}", escape_string(&prog.stdout));
+        },
+        Err(e) => {
+            let linker_not_found = e.kind() == io::ErrorKind::NotFound;
+
+            let mut linker_error = {
+                if linker_not_found {
+                    sess.struct_err(&format!("linker `{}` not found", pname.display()))
+                } else {
+                    sess.struct_err(&format!("could not exec the linker `{}`", pname.display()))
+                }
+            };
+
+            linker_error.note(&e.to_string());
+
+            if !linker_not_found {
+                linker_error.note(&format!("{:?}", &cmd));
+            }
+
+            linker_error.emit();
+
+            if sess.target.target.options.is_like_msvc && linker_not_found {
+                sess.note_without_error("the msvc targets depend on the msvc linker \
+                    but `link.exe` was not found");
+                sess.note_without_error("please ensure that VS 2013, VS 2015 or VS 2017 \
+                    was installed with the Visual C++ option");
+            }
+            sess.abort_if_errors();
+        }
+    }
+
+
+    // On macOS, debuggers need this utility to get run to do some munging of
+    // the symbols. Note, though, that if the object files are being preserved
+    // for their debug information there's no need for us to run dsymutil.
+    if sess.target.target.options.is_like_osx &&
+        sess.opts.debuginfo != DebugInfo::None &&
+        !preserve_objects_for_their_debuginfo(sess)
+    {
+        if let Err(e) = Command::new("dsymutil").arg(out_filename).output() {
+            sess.fatal(&format!("failed to run dsymutil: {}", e))
+        }
+    }
+
+    if sess.opts.target_triple.triple() == "wasm32-unknown-unknown" {
+        super::wasm::add_producer_section(
+            &out_filename,
+            &sess.edition().to_string(),
+            option_env!("CFG_VERSION").unwrap_or("unknown"),
+        );
+    }
+}
+
 /// Returns a boolean indicating whether the specified crate should be ignored
 /// during LTO.
 ///
@@ -200,3 +780,898 @@ pub fn linker_and_flavor(sess: &Session) -> (PathBuf, LinkerFlavor) {
 
     bug!("Not enough information provided to determine how to invoke the linker");
 }
+
+/// Returns a boolean indicating whether we should preserve the object files on
+/// the filesystem for their debug information. This is often useful with
+/// split-dwarf like schemes.
+pub fn preserve_objects_for_their_debuginfo(sess: &Session) -> bool {
+    // If the objects don't have debuginfo there's nothing to preserve.
+    if sess.opts.debuginfo == config::DebugInfo::None {
+        return false
+    }
+
+    // If we're only producing artifacts that are archives, no need to preserve
+    // the objects as they're losslessly contained inside the archives.
+    let output_linked = sess.crate_types.borrow()
+        .iter()
+        .any(|&x| x != config::CrateType::Rlib && x != config::CrateType::Staticlib);
+    if !output_linked {
+        return false
+    }
+
+    // If we're on OSX then the equivalent of split dwarf is turned on by
+    // default. The final executable won't actually have any debug information
+    // except it'll have pointers to elsewhere. Historically we've always run
+    // `dsymutil` to "link all the dwarf together" but this is actually sort of
+    // a bummer for incremental compilation! (the whole point of split dwarf is
+    // that you don't do this sort of dwarf link).
+    //
+    // Basically as a result this just means that if we're on OSX and we're
+    // *not* running dsymutil then the object files are the only source of truth
+    // for debug information, so we must preserve them.
+    if sess.target.target.options.is_like_osx {
+        match sess.opts.debugging_opts.run_dsymutil {
+            // dsymutil is not being run, preserve objects
+            Some(false) => return true,
+
+            // dsymutil is being run, no need to preserve the objects
+            Some(true) => return false,
+
+            // The default historical behavior was to always run dsymutil, so
+            // we're preserving that temporarily, but we're likely to switch the
+            // default soon.
+            None => return false,
+        }
+    }
+
+    false
+}
+
+pub fn archive_search_paths(sess: &Session) -> Vec<PathBuf> {
+    sess.target_filesearch(PathKind::Native).search_path_dirs()
+}
+
+enum RlibFlavor {
+    Normal,
+    StaticlibBase,
+}
+
+pub fn print_native_static_libs(sess: &Session, all_native_libs: &[NativeLibrary]) {
+    let lib_args: Vec<_> = all_native_libs.iter()
+        .filter(|l| relevant_lib(sess, l))
+        .filter_map(|lib| {
+            let name = lib.name?;
+            match lib.kind {
+                NativeLibraryKind::NativeStaticNobundle |
+                NativeLibraryKind::NativeUnknown => {
+                    if sess.target.target.options.is_like_msvc {
+                        Some(format!("{}.lib", name))
+                    } else {
+                        Some(format!("-l{}", name))
+                    }
+                },
+                NativeLibraryKind::NativeFramework => {
+                    // ld-only syntax, since there are no frameworks in MSVC
+                    Some(format!("-framework {}", name))
+                },
+                // These are included, no need to print them
+                NativeLibraryKind::NativeStatic => None,
+            }
+        })
+        .collect();
+    if !lib_args.is_empty() {
+        sess.note_without_error("Link against the following native artifacts when linking \
+                                 against this static library. The order and any duplication \
+                                 can be significant on some platforms.");
+        // Prefix for greppability
+        sess.note_without_error(&format!("native-static-libs: {}", &lib_args.join(" ")));
+    }
+}
+
+pub fn get_file_path(sess: &Session, name: &str) -> PathBuf {
+    let fs = sess.target_filesearch(PathKind::Native);
+    let file_path = fs.get_lib_path().join(name);
+    if file_path.exists() {
+        return file_path
+    }
+    for search_path in fs.search_paths() {
+        let file_path = search_path.dir.join(name);
+        if file_path.exists() {
+            return file_path
+        }
+    }
+    PathBuf::from(name)
+}
+
+pub fn exec_linker(sess: &Session, cmd: &mut Command, out_filename: &Path, tmpdir: &Path)
+    -> io::Result<Output>
+{
+    // When attempting to spawn the linker we run a risk of blowing out the
+    // size limits for spawning a new process with respect to the arguments
+    // we pass on the command line.
+    //
+    // Here we attempt to handle errors from the OS saying "your list of
+    // arguments is too big" by reinvoking the linker again with an `@`-file
+    // that contains all the arguments. The theory is that this is then
+    // accepted on all linkers and the linker will read all its options out of
+    // there instead of looking at the command line.
+    if !cmd.very_likely_to_exceed_some_spawn_limit() {
+        match cmd.command().stdout(Stdio::piped()).stderr(Stdio::piped()).spawn() {
+            Ok(child) => {
+                let output = child.wait_with_output();
+                flush_linked_file(&output, out_filename)?;
+                return output;
+            }
+            Err(ref e) if command_line_too_big(e) => {
+                info!("command line to linker was too big: {}", e);
+            }
+            Err(e) => return Err(e)
+        }
+    }
+
+    info!("falling back to passing arguments to linker via an @-file");
+    let mut cmd2 = cmd.clone();
+    let mut args = String::new();
+    for arg in cmd2.take_args() {
+        args.push_str(&Escape {
+            arg: arg.to_str().unwrap(),
+            is_like_msvc: sess.target.target.options.is_like_msvc,
+        }.to_string());
+        args.push_str("\n");
+    }
+    let file = tmpdir.join("linker-arguments");
+    let bytes = if sess.target.target.options.is_like_msvc {
+        let mut out = Vec::with_capacity((1 + args.len()) * 2);
+        // start the stream with a UTF-16 BOM
+        for c in std::iter::once(0xFEFF).chain(args.encode_utf16()) {
+            // encode in little endian
+            out.push(c as u8);
+            out.push((c >> 8) as u8);
+        }
+        out
+    } else {
+        args.into_bytes()
+    };
+    fs::write(&file, &bytes)?;
+    cmd2.arg(format!("@{}", file.display()));
+    info!("invoking linker {:?}", cmd2);
+    let output = cmd2.output();
+    flush_linked_file(&output, out_filename)?;
+    return output;
+
+    #[cfg(unix)]
+    fn flush_linked_file(_: &io::Result<Output>, _: &Path) -> io::Result<()> {
+        Ok(())
+    }
+
+    #[cfg(windows)]
+    fn flush_linked_file(command_output: &io::Result<Output>, out_filename: &Path)
+        -> io::Result<()>
+    {
+        // On Windows, under high I/O load, output buffers are sometimes not flushed,
+        // even long after process exit, causing nasty, non-reproducible output bugs.
+        //
+        // File::sync_all() calls FlushFileBuffers() down the line, which solves the problem.
+        //
+        // А full writeup of the original Chrome bug can be found at
+        // randomascii.wordpress.com/2018/02/25/compiler-bug-linker-bug-windows-kernel-bug/amp
+
+        if let &Ok(ref out) = command_output {
+            if out.status.success() {
+                if let Ok(of) = fs::OpenOptions::new().write(true).open(out_filename) {
+                    of.sync_all()?;
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    #[cfg(unix)]
+    fn command_line_too_big(err: &io::Error) -> bool {
+        err.raw_os_error() == Some(::libc::E2BIG)
+    }
+
+    #[cfg(windows)]
+    fn command_line_too_big(err: &io::Error) -> bool {
+        const ERROR_FILENAME_EXCED_RANGE: i32 = 206;
+        err.raw_os_error() == Some(ERROR_FILENAME_EXCED_RANGE)
+    }
+
+    struct Escape<'a> {
+        arg: &'a str,
+        is_like_msvc: bool,
+    }
+
+    impl<'a> fmt::Display for Escape<'a> {
+        fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            if self.is_like_msvc {
+                // This is "documented" at
+                // https://msdn.microsoft.com/en-us/library/4xdcbak7.aspx
+                //
+                // Unfortunately there's not a great specification of the
+                // syntax I could find online (at least) but some local
+                // testing showed that this seemed sufficient-ish to catch
+                // at least a few edge cases.
+                write!(f, "\"")?;
+                for c in self.arg.chars() {
+                    match c {
+                        '"' => write!(f, "\\{}", c)?,
+                        c => write!(f, "{}", c)?,
+                    }
+                }
+                write!(f, "\"")?;
+            } else {
+                // This is documented at https://linux.die.net/man/1/ld, namely:
+                //
+                // > Options in file are separated by whitespace. A whitespace
+                // > character may be included in an option by surrounding the
+                // > entire option in either single or double quotes. Any
+                // > character (including a backslash) may be included by
+                // > prefixing the character to be included with a backslash.
+                //
+                // We put an argument on each line, so all we need to do is
+                // ensure the line is interpreted as one whole argument.
+                for c in self.arg.chars() {
+                    match c {
+                        '\\' | ' ' => write!(f, "\\{}", c)?,
+                        c => write!(f, "{}", c)?,
+                    }
+                }
+            }
+            Ok(())
+        }
+    }
+}
+
+fn link_args<'a, B: ArchiveBuilder<'a>>(cmd: &mut dyn Linker,
+             flavor: LinkerFlavor,
+             sess: &'a Session,
+             crate_type: config::CrateType,
+             tmpdir: &Path,
+             out_filename: &Path,
+             codegen_results: &CodegenResults) {
+
+    // Linker plugins should be specified early in the list of arguments
+    cmd.linker_plugin_lto();
+
+    // The default library location, we need this to find the runtime.
+    // The location of crates will be determined as needed.
+    let lib_path = sess.target_filesearch(PathKind::All).get_lib_path();
+
+    // target descriptor
+    let t = &sess.target.target;
+
+    cmd.include_path(&fix_windows_verbatim_for_gcc(&lib_path));
+    for obj in codegen_results.modules.iter().filter_map(|m| m.object.as_ref()) {
+        cmd.add_object(obj);
+    }
+    cmd.output_filename(out_filename);
+
+    if crate_type == config::CrateType::Executable &&
+       sess.target.target.options.is_like_windows {
+        if let Some(ref s) = codegen_results.windows_subsystem {
+            cmd.subsystem(s);
+        }
+    }
+
+    // If we're building a dynamic library then some platforms need to make sure
+    // that all symbols are exported correctly from the dynamic library.
+    if crate_type != config::CrateType::Executable ||
+       sess.target.target.options.is_like_emscripten {
+        cmd.export_symbols(tmpdir, crate_type);
+    }
+
+    // When linking a dynamic library, we put the metadata into a section of the
+    // executable. This metadata is in a separate object file from the main
+    // object file, so we link that in here.
+    if crate_type == config::CrateType::Dylib ||
+       crate_type == config::CrateType::ProcMacro {
+        if let Some(obj) = codegen_results.metadata_module.object.as_ref() {
+            cmd.add_object(obj);
+        }
+    }
+
+    let obj = codegen_results.allocator_module
+        .as_ref()
+        .and_then(|m| m.object.as_ref());
+    if let Some(obj) = obj {
+        cmd.add_object(obj);
+    }
+
+    // Try to strip as much out of the generated object by removing unused
+    // sections if possible. See more comments in linker.rs
+    if !sess.opts.cg.link_dead_code {
+        let keep_metadata = crate_type == config::CrateType::Dylib;
+        cmd.gc_sections(keep_metadata);
+    }
+
+    let used_link_args = &codegen_results.crate_info.link_args;
+
+    if crate_type == config::CrateType::Executable {
+        let mut position_independent_executable = false;
+
+        if t.options.position_independent_executables {
+            let empty_vec = Vec::new();
+            let args = sess.opts.cg.link_args.as_ref().unwrap_or(&empty_vec);
+            let more_args = &sess.opts.cg.link_arg;
+            let mut args = args.iter().chain(more_args.iter()).chain(used_link_args.iter());
+
+            if is_pic(sess) && !sess.crt_static() && !args.any(|x| *x == "-static") {
+                position_independent_executable = true;
+            }
+        }
+
+        if position_independent_executable {
+            cmd.position_independent_executable();
+        } else {
+            // recent versions of gcc can be configured to generate position
+            // independent executables by default. We have to pass -no-pie to
+            // explicitly turn that off. Not applicable to ld.
+            if sess.target.target.options.linker_is_gnu
+                && flavor != LinkerFlavor::Ld {
+                cmd.no_position_independent_executable();
+            }
+        }
+    }
+
+    let relro_level = match sess.opts.debugging_opts.relro_level {
+        Some(level) => level,
+        None => t.options.relro_level,
+    };
+    match relro_level {
+        RelroLevel::Full => {
+            cmd.full_relro();
+        },
+        RelroLevel::Partial => {
+            cmd.partial_relro();
+        },
+        RelroLevel::Off => {
+            cmd.no_relro();
+        },
+        RelroLevel::None => {
+        },
+    }
+
+    // Pass optimization flags down to the linker.
+    cmd.optimize();
+
+    // Pass debuginfo flags down to the linker.
+    cmd.debuginfo();
+
+    // We want to, by default, prevent the compiler from accidentally leaking in
+    // any system libraries, so we may explicitly ask linkers to not link to any
+    // libraries by default. Note that this does not happen for windows because
+    // windows pulls in some large number of libraries and I couldn't quite
+    // figure out which subset we wanted.
+    //
+    // This is all naturally configurable via the standard methods as well.
+    if !sess.opts.cg.default_linker_libraries.unwrap_or(false) &&
+        t.options.no_default_libraries
+    {
+        cmd.no_default_libraries();
+    }
+
+    // Take careful note of the ordering of the arguments we pass to the linker
+    // here. Linkers will assume that things on the left depend on things to the
+    // right. Things on the right cannot depend on things on the left. This is
+    // all formally implemented in terms of resolving symbols (libs on the right
+    // resolve unknown symbols of libs on the left, but not vice versa).
+    //
+    // For this reason, we have organized the arguments we pass to the linker as
+    // such:
+    //
+    //  1. The local object that LLVM just generated
+    //  2. Local native libraries
+    //  3. Upstream rust libraries
+    //  4. Upstream native libraries
+    //
+    // The rationale behind this ordering is that those items lower down in the
+    // list can't depend on items higher up in the list. For example nothing can
+    // depend on what we just generated (e.g., that'd be a circular dependency).
+    // Upstream rust libraries are not allowed to depend on our local native
+    // libraries as that would violate the structure of the DAG, in that
+    // scenario they are required to link to them as well in a shared fashion.
+    //
+    // Note that upstream rust libraries may contain native dependencies as
+    // well, but they also can't depend on what we just started to add to the
+    // link line. And finally upstream native libraries can't depend on anything
+    // in this DAG so far because they're only dylibs and dylibs can only depend
+    // on other dylibs (e.g., other native deps).
+    add_local_native_libraries(cmd, sess, codegen_results);
+    add_upstream_rust_crates::<B>(cmd, sess, codegen_results, crate_type, tmpdir);
+    add_upstream_native_libraries(cmd, sess, codegen_results, crate_type);
+
+    // Tell the linker what we're doing.
+    if crate_type != config::CrateType::Executable {
+        cmd.build_dylib(out_filename);
+    }
+    if crate_type == config::CrateType::Executable && sess.crt_static() {
+        cmd.build_static_executable();
+    }
+
+    if sess.opts.debugging_opts.pgo_gen.enabled() {
+        cmd.pgo_gen();
+    }
+
+    // FIXME (#2397): At some point we want to rpath our guesses as to
+    // where extern libraries might live, based on the
+    // addl_lib_search_paths
+    if sess.opts.cg.rpath {
+        let target_triple = sess.opts.target_triple.triple();
+        let mut get_install_prefix_lib_path = || {
+            let install_prefix = option_env!("CFG_PREFIX").expect("CFG_PREFIX");
+            let tlib = filesearch::relative_target_lib_path(&sess.sysroot, target_triple);
+            let mut path = PathBuf::from(install_prefix);
+            path.push(&tlib);
+
+            path
+        };
+        let mut rpath_config = RPathConfig {
+            used_crates: &codegen_results.crate_info.used_crates_dynamic,
+            out_filename: out_filename.to_path_buf(),
+            has_rpath: sess.target.target.options.has_rpath,
+            is_like_osx: sess.target.target.options.is_like_osx,
+            linker_is_gnu: sess.target.target.options.linker_is_gnu,
+            get_install_prefix_lib_path: &mut get_install_prefix_lib_path,
+        };
+        cmd.args(&rpath::get_rpath_flags(&mut rpath_config));
+    }
+
+    // Finally add all the linker arguments provided on the command line along
+    // with any #[link_args] attributes found inside the crate
+    if let Some(ref args) = sess.opts.cg.link_args {
+        cmd.args(args);
+    }
+    cmd.args(&sess.opts.cg.link_arg);
+    cmd.args(&used_link_args);
+}
+
+// # Native library linking
+//
+// User-supplied library search paths (-L on the command line). These are
+// the same paths used to find Rust crates, so some of them may have been
+// added already by the previous crate linking code. This only allows them
+// 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.
+//
+// Also note that the native libraries linked here are only the ones located
+// in the current crate. Upstream crates with native library dependencies
+// may have their native library pulled in above.
+pub fn add_local_native_libraries(cmd: &mut dyn Linker,
+                              sess: &Session,
+                              codegen_results: &CodegenResults) {
+    let filesearch = sess.target_filesearch(PathKind::All);
+    for search_path in filesearch.search_paths() {
+        match search_path.kind {
+            PathKind::Framework => { cmd.framework_path(&search_path.dir); }
+            _ => { cmd.include_path(&fix_windows_verbatim_for_gcc(&search_path.dir)); }
+        }
+    }
+
+    let relevant_libs = codegen_results.crate_info.used_libraries.iter().filter(|l| {
+        relevant_lib(sess, l)
+    });
+
+    let search_path = archive_search_paths(sess);
+    for lib in relevant_libs {
+        let name = match lib.name {
+            Some(ref l) => l,
+            None => continue,
+        };
+        match lib.kind {
+            NativeLibraryKind::NativeUnknown => cmd.link_dylib(&name.as_str()),
+            NativeLibraryKind::NativeFramework => cmd.link_framework(&name.as_str()),
+            NativeLibraryKind::NativeStaticNobundle => cmd.link_staticlib(&name.as_str()),
+            NativeLibraryKind::NativeStatic => cmd.link_whole_staticlib(&name.as_str(),
+                                                                        &search_path)
+        }
+    }
+}
+
+// # Rust Crate linking
+//
+// Rust crates are not considered at all when creating an rlib output. All
+// dependencies will be linked when producing the final output (instead of
+// the intermediate rlib version)
+fn add_upstream_rust_crates<'a, B: ArchiveBuilder<'a>>(cmd: &mut dyn Linker,
+                            sess: &'a Session,
+                            codegen_results: &CodegenResults,
+                            crate_type: config::CrateType,
+                            tmpdir: &Path) {
+    // All of the heavy lifting has previously been accomplished by the
+    // dependency_format module of the compiler. This is just crawling the
+    // output of that module, adding crates as necessary.
+    //
+    // Linking to a rlib involves just passing it to the linker (the linker
+    // will slurp up the object files inside), and linking to a dynamic library
+    // involves just passing the right -l flag.
+
+    let formats = sess.dependency_formats.borrow();
+    let data = formats.get(&crate_type).unwrap();
+
+    // Invoke get_used_crates to ensure that we get a topological sorting of
+    // crates.
+    let deps = &codegen_results.crate_info.used_crates_dynamic;
+
+    // There's a few internal crates in the standard library (aka libcore and
+    // libstd) which actually have a circular dependence upon one another. This
+    // currently arises through "weak lang items" where libcore requires things
+    // like `rust_begin_unwind` but libstd ends up defining it. To get this
+    // circular dependence to work correctly in all situations we'll need to be
+    // sure to correctly apply the `--start-group` and `--end-group` options to
+    // GNU linkers, otherwise if we don't use any other symbol from the standard
+    // library it'll get discarded and the whole application won't link.
+    //
+    // In this loop we're calculating the `group_end`, after which crate to
+    // pass `--end-group` and `group_start`, before which crate to pass
+    // `--start-group`. We currently do this by passing `--end-group` after
+    // the first crate (when iterating backwards) that requires a lang item
+    // defined somewhere else. Once that's set then when we've defined all the
+    // necessary lang items we'll pass `--start-group`.
+    //
+    // Note that this isn't amazing logic for now but it should do the trick
+    // for the current implementation of the standard library.
+    let mut group_end = None;
+    let mut group_start = None;
+    let mut end_with = FxHashSet::default();
+    let info = &codegen_results.crate_info;
+    for &(cnum, _) in deps.iter().rev() {
+        if let Some(missing) = info.missing_lang_items.get(&cnum) {
+            end_with.extend(missing.iter().cloned());
+            if end_with.len() > 0 && group_end.is_none() {
+                group_end = Some(cnum);
+            }
+        }
+        end_with.retain(|item| info.lang_item_to_crate.get(item) != Some(&cnum));
+        if end_with.len() == 0 && group_end.is_some() {
+            group_start = Some(cnum);
+            break
+        }
+    }
+
+    // If we didn't end up filling in all lang items from upstream crates then
+    // we'll be filling it in with our crate. This probably means we're the
+    // standard library itself, so skip this for now.
+    if group_end.is_some() && group_start.is_none() {
+        group_end = None;
+    }
+
+    let mut compiler_builtins = None;
+
+    for &(cnum, _) in deps.iter() {
+        if group_start == Some(cnum) {
+            cmd.group_start();
+        }
+
+        // We may not pass all crates through to the linker. Some crates may
+        // appear statically in an existing dylib, meaning we'll pick up all the
+        // symbols from the dylib.
+        let src = &codegen_results.crate_info.used_crate_source[&cnum];
+        match data[cnum.as_usize() - 1] {
+            _ if codegen_results.crate_info.profiler_runtime == Some(cnum) => {
+                add_static_crate::<B>(cmd, sess, codegen_results, tmpdir, crate_type, cnum);
+            }
+            _ if codegen_results.crate_info.sanitizer_runtime == Some(cnum) => {
+                link_sanitizer_runtime::<B>(cmd, sess, codegen_results, tmpdir, cnum);
+            }
+            // compiler-builtins are always placed last to ensure that they're
+            // linked correctly.
+            _ if codegen_results.crate_info.compiler_builtins == Some(cnum) => {
+                assert!(compiler_builtins.is_none());
+                compiler_builtins = Some(cnum);
+            }
+            Linkage::NotLinked |
+            Linkage::IncludedFromDylib => {}
+            Linkage::Static => {
+                add_static_crate::<B>(cmd, sess, codegen_results, tmpdir, crate_type, cnum);
+            }
+            Linkage::Dynamic => {
+                add_dynamic_crate(cmd, sess, &src.dylib.as_ref().unwrap().0)
+            }
+        }
+
+        if group_end == Some(cnum) {
+            cmd.group_end();
+        }
+    }
+
+    // compiler-builtins are always placed last to ensure that they're
+    // linked correctly.
+    // We must always link the `compiler_builtins` crate statically. Even if it
+    // was already "included" in a dylib (e.g., `libstd` when `-C prefer-dynamic`
+    // is used)
+    if let Some(cnum) = compiler_builtins {
+        add_static_crate::<B>(cmd, sess, codegen_results, tmpdir, crate_type, cnum);
+    }
+
+    // Converts a library file-stem into a cc -l argument
+    fn unlib<'a>(config: &config::Config, stem: &'a str) -> &'a str {
+        if stem.starts_with("lib") && !config.target.options.is_like_windows {
+            &stem[3..]
+        } else {
+            stem
+        }
+    }
+
+    // We must link the sanitizer runtime using -Wl,--whole-archive but since
+    // it's packed in a .rlib, it contains stuff that are not objects that will
+    // make the linker error. So we must remove those bits from the .rlib before
+    // linking it.
+    fn link_sanitizer_runtime<'a, B: ArchiveBuilder<'a>>(cmd: &mut dyn Linker,
+                              sess: &'a Session,
+                              codegen_results: &CodegenResults,
+                              tmpdir: &Path,
+                              cnum: CrateNum) {
+        let src = &codegen_results.crate_info.used_crate_source[&cnum];
+        let cratepath = &src.rlib.as_ref().unwrap().0;
+
+        if sess.target.target.options.is_like_osx {
+            // On Apple platforms, the sanitizer is always built as a dylib, and
+            // LLVM will link to `@rpath/*.dylib`, so we need to specify an
+            // rpath to the library as well (the rpath should be absolute, see
+            // PR #41352 for details).
+            //
+            // FIXME: Remove this logic into librustc_*san once Cargo supports it
+            let rpath = cratepath.parent().unwrap();
+            let rpath = rpath.to_str().expect("non-utf8 component in path");
+            cmd.args(&["-Wl,-rpath".into(), "-Xlinker".into(), rpath.into()]);
+        }
+
+        let dst = tmpdir.join(cratepath.file_name().unwrap());
+        let mut archive = <B as ArchiveBuilder>::new(sess, &dst, Some(cratepath));
+        archive.update_symbols();
+
+        for f in archive.src_files() {
+            if f.ends_with(RLIB_BYTECODE_EXTENSION) || f == METADATA_FILENAME {
+                archive.remove_file(&f);
+            }
+        }
+
+        archive.build();
+
+        cmd.link_whole_rlib(&dst);
+    }
+
+    // Adds the static "rlib" versions of all crates to the command line.
+    // There's a bit of magic which happens here specifically related to LTO and
+    // dynamic libraries. Specifically:
+    //
+    // * For LTO, we remove upstream object files.
+    // * For dylibs we remove metadata and bytecode from upstream rlibs
+    //
+    // When performing LTO, almost(*) all of the bytecode from the upstream
+    // libraries has already been included in our object file output. As a
+    // result we need to remove the object files in the upstream libraries so
+    // the linker doesn't try to include them twice (or whine about duplicate
+    // symbols). We must continue to include the rest of the rlib, however, as
+    // it may contain static native libraries which must be linked in.
+    //
+    // (*) Crates marked with `#![no_builtins]` don't participate in LTO and
+    // their bytecode wasn't included. The object files in those libraries must
+    // still be passed to the linker.
+    //
+    // When making a dynamic library, linkers by default don't include any
+    // object files in an archive if they're not necessary to resolve the link.
+    // We basically want to convert the archive (rlib) to a dylib, though, so we
+    // *do* want everything included in the output, regardless of whether the
+    // linker thinks it's needed or not. As a result we must use the
+    // --whole-archive option (or the platform equivalent). When using this
+    // option the linker will fail if there are non-objects in the archive (such
+    // as our own metadata and/or bytecode). All in all, for rlibs to be
+    // entirely included in dylibs, we need to remove all non-object files.
+    //
+    // Note, however, that if we're not doing LTO or we're not producing a dylib
+    // (aka we're making an executable), we can just pass the rlib blindly to
+    // the linker (fast) because it's fine if it's not actually included as
+    // we're at the end of the dependency chain.
+    fn add_static_crate<'a, B: ArchiveBuilder<'a>>(cmd: &mut dyn Linker,
+                        sess: &'a Session,
+                        codegen_results: &CodegenResults,
+                        tmpdir: &Path,
+                        crate_type: config::CrateType,
+                        cnum: CrateNum) {
+        let src = &codegen_results.crate_info.used_crate_source[&cnum];
+        let cratepath = &src.rlib.as_ref().unwrap().0;
+
+        // See the comment above in `link_staticlib` and `link_rlib` for why if
+        // there's a static library that's not relevant we skip all object
+        // files.
+        let native_libs = &codegen_results.crate_info.native_libraries[&cnum];
+        let skip_native = native_libs.iter().any(|lib| {
+            lib.kind == NativeLibraryKind::NativeStatic && !relevant_lib(sess, lib)
+        });
+
+        if (!are_upstream_rust_objects_already_included(sess) ||
+            ignored_for_lto(sess, &codegen_results.crate_info, cnum)) &&
+           crate_type != config::CrateType::Dylib &&
+           !skip_native {
+            cmd.link_rlib(&fix_windows_verbatim_for_gcc(cratepath));
+            return
+        }
+
+        let dst = tmpdir.join(cratepath.file_name().unwrap());
+        let name = cratepath.file_name().unwrap().to_str().unwrap();
+        let name = &name[3..name.len() - 5]; // chop off lib/.rlib
+
+        time_ext(sess.time_extended(), Some(sess), &format!("altering {}.rlib", name), || {
+            let mut archive = <B as ArchiveBuilder>::new(sess, &dst, Some(cratepath));
+            archive.update_symbols();
+
+            let mut any_objects = false;
+            for f in archive.src_files() {
+                if f.ends_with(RLIB_BYTECODE_EXTENSION) || f == METADATA_FILENAME {
+                    archive.remove_file(&f);
+                    continue
+                }
+
+                let canonical = f.replace("-", "_");
+                let canonical_name = name.replace("-", "_");
+
+                // Look for `.rcgu.o` at the end of the filename to conclude
+                // that this is a Rust-related object file.
+                fn looks_like_rust(s: &str) -> bool {
+                    let path = Path::new(s);
+                    let ext = path.extension().and_then(|s| s.to_str());
+                    if ext != Some(OutputType::Object.extension()) {
+                        return false
+                    }
+                    let ext2 = path.file_stem()
+                        .and_then(|s| Path::new(s).extension())
+                        .and_then(|s| s.to_str());
+                    ext2 == Some(RUST_CGU_EXT)
+                }
+
+                let is_rust_object =
+                    canonical.starts_with(&canonical_name) &&
+                    looks_like_rust(&f);
+
+                // If we've been requested to skip all native object files
+                // (those not generated by the rust compiler) then we can skip
+                // this file. See above for why we may want to do this.
+                let skip_because_cfg_say_so = skip_native && !is_rust_object;
+
+                // If we're performing LTO and this is a rust-generated object
+                // file, then we don't need the object file as it's part of the
+                // LTO module. Note that `#![no_builtins]` is excluded from LTO,
+                // though, so we let that object file slide.
+                let skip_because_lto = are_upstream_rust_objects_already_included(sess) &&
+                    is_rust_object &&
+                    (sess.target.target.options.no_builtins ||
+                     !codegen_results.crate_info.is_no_builtins.contains(&cnum));
+
+                if skip_because_cfg_say_so || skip_because_lto {
+                    archive.remove_file(&f);
+                } else {
+                    any_objects = true;
+                }
+            }
+
+            if !any_objects {
+                return
+            }
+            archive.build();
+
+            // If we're creating a dylib, then we need to include the
+            // whole of each object in our archive into that artifact. This is
+            // because a `dylib` can be reused as an intermediate artifact.
+            //
+            // Note, though, that we don't want to include the whole of a
+            // compiler-builtins crate (e.g., compiler-rt) because it'll get
+            // repeatedly linked anyway.
+            if crate_type == config::CrateType::Dylib &&
+                codegen_results.crate_info.compiler_builtins != Some(cnum) {
+                cmd.link_whole_rlib(&fix_windows_verbatim_for_gcc(&dst));
+            } else {
+                cmd.link_rlib(&fix_windows_verbatim_for_gcc(&dst));
+            }
+        });
+    }
+
+    // Same thing as above, but for dynamic crates instead of static crates.
+    fn add_dynamic_crate(cmd: &mut dyn Linker, sess: &Session, cratepath: &Path) {
+        // Just need to tell the linker about where the library lives and
+        // what its name is
+        let parent = cratepath.parent();
+        if let Some(dir) = parent {
+            cmd.include_path(&fix_windows_verbatim_for_gcc(dir));
+        }
+        let filestem = cratepath.file_stem().unwrap().to_str().unwrap();
+        cmd.link_rust_dylib(&unlib(&sess.target, filestem),
+                            parent.unwrap_or(Path::new("")));
+    }
+}
+
+// Link in all of our upstream crates' native dependencies. Remember that
+// all of these upstream native dependencies are all non-static
+// dependencies. We've got two cases then:
+//
+// 1. The upstream crate is an rlib. In this case we *must* link in the
+// native dependency because the rlib is just an archive.
+//
+// 2. The upstream crate is a dylib. In order to use the dylib, we have to
+// have the dependency present on the system somewhere. Thus, we don't
+// gain a whole lot from not linking in the dynamic dependency to this
+// crate as well.
+//
+// The use case for this is a little subtle. In theory the native
+// dependencies of a crate are purely an implementation detail of the crate
+// itself, but the problem arises with generic and inlined functions. If a
+// generic function calls a native function, then the generic function must
+// be instantiated in the target crate, meaning that the native symbol must
+// also be resolved in the target crate.
+pub fn add_upstream_native_libraries(cmd: &mut dyn Linker,
+                                 sess: &Session,
+                                 codegen_results: &CodegenResults,
+                                 crate_type: config::CrateType) {
+    // Be sure to use a topological sorting of crates because there may be
+    // interdependencies between native libraries. When passing -nodefaultlibs,
+    // for example, almost all native libraries depend on libc, so we have to
+    // make sure that's all the way at the right (liblibc is near the base of
+    // the dependency chain).
+    //
+    // This passes RequireStatic, but the actual requirement doesn't matter,
+    // we're just getting an ordering of crate numbers, we're not worried about
+    // the paths.
+    let formats = sess.dependency_formats.borrow();
+    let data = formats.get(&crate_type).unwrap();
+
+    let crates = &codegen_results.crate_info.used_crates_static;
+    for &(cnum, _) in crates {
+        for lib in codegen_results.crate_info.native_libraries[&cnum].iter() {
+            let name = match lib.name {
+                Some(ref l) => l,
+                None => continue,
+            };
+            if !relevant_lib(sess, &lib) {
+                continue
+            }
+            match lib.kind {
+                NativeLibraryKind::NativeUnknown => cmd.link_dylib(&name.as_str()),
+                NativeLibraryKind::NativeFramework => cmd.link_framework(&name.as_str()),
+                NativeLibraryKind::NativeStaticNobundle => {
+                    // Link "static-nobundle" native libs only if the crate they originate from
+                    // is being linked statically to the current crate.  If it's linked dynamically
+                    // or is an rlib already included via some other dylib crate, the symbols from
+                    // native libs will have already been included in that dylib.
+                    if data[cnum.as_usize() - 1] == Linkage::Static {
+                        cmd.link_staticlib(&name.as_str())
+                    }
+                },
+                // ignore statically included native libraries here as we've
+                // already included them when we included the rust library
+                // previously
+                NativeLibraryKind::NativeStatic => {}
+            }
+        }
+    }
+}
+
+pub fn relevant_lib(sess: &Session, lib: &NativeLibrary) -> bool {
+    match lib.cfg {
+        Some(ref cfg) => syntax::attr::cfg_matches(cfg, &sess.parse_sess, None),
+        None => true,
+    }
+}
+
+pub fn are_upstream_rust_objects_already_included(sess: &Session) -> bool {
+    match sess.lto() {
+        config::Lto::Fat => true,
+        config::Lto::Thin => {
+            // If we defer LTO to the linker, we haven't run LTO ourselves, so
+            // any upstream object files have not been copied yet.
+            !sess.opts.cg.linker_plugin_lto.enabled()
+        }
+        config::Lto::No |
+        config::Lto::ThinLocal => false,
+    }
+}
+
+fn is_pic(sess: &Session) -> bool {
+    let reloc_model_arg = match sess.opts.cg.relocation_model {
+        Some(ref s) => &s[..],
+        None => &sess.target.target.options.relocation_model[..],
+    };
+
+    reloc_model_arg == "pic"
+}
diff --git a/src/librustc_codegen_ssa/back/mod.rs b/src/librustc_codegen_ssa/back/mod.rs
index 888108408fb..a16d099ee3e 100644
--- a/src/librustc_codegen_ssa/back/mod.rs
+++ b/src/librustc_codegen_ssa/back/mod.rs
@@ -5,3 +5,5 @@ pub mod link;
 pub mod command;
 pub mod symbol_export;
 pub mod archive;
+pub mod rpath;
+pub mod wasm;
diff --git a/src/librustc_codegen_llvm/back/rpath.rs b/src/librustc_codegen_ssa/back/rpath.rs
index 2b7abcb52be..2b7abcb52be 100644
--- a/src/librustc_codegen_llvm/back/rpath.rs
+++ b/src/librustc_codegen_ssa/back/rpath.rs
diff --git a/src/librustc_codegen_llvm/back/wasm.rs b/src/librustc_codegen_ssa/back/wasm.rs
index f90bb89fbe8..f90bb89fbe8 100644
--- a/src/librustc_codegen_llvm/back/wasm.rs
+++ b/src/librustc_codegen_ssa/back/wasm.rs
diff --git a/src/librustc_codegen_ssa/debuginfo.rs b/src/librustc_codegen_ssa/debuginfo/mod.rs
index aa7cdbed994..d60a2e0cb13 100644
--- a/src/librustc_codegen_ssa/debuginfo.rs
+++ b/src/librustc_codegen_ssa/debuginfo/mod.rs
@@ -1,6 +1,8 @@
 use syntax_pos::{BytePos, Span};
 use rustc::hir::def_id::CrateNum;
 
+pub mod type_names;
+
 pub enum FunctionDebugContext<D> {
     RegularContext(FunctionDebugContextData<D>),
     DebugInfoDisabled,
diff --git a/src/librustc_codegen_llvm/debuginfo/type_names.rs b/src/librustc_codegen_ssa/debuginfo/type_names.rs
index eff7cd1bc8a..fee6c5b04d0 100644
--- a/src/librustc_codegen_llvm/debuginfo/type_names.rs
+++ b/src/librustc_codegen_ssa/debuginfo/type_names.rs
@@ -1,31 +1,26 @@
 // Type Names for Debug Info.
 
-use crate::common::CodegenCx;
-use rustc::hir::def_id::DefId;
-use rustc::ty::subst::SubstsRef;
-use rustc::ty::{self, Ty};
-use rustc_codegen_ssa::traits::*;
+use rustc::hir::{self, def_id::DefId};
+use rustc::ty::{self, Ty, TyCtxt, subst::SubstsRef};
 use rustc_data_structures::fx::FxHashSet;
 
-use rustc::hir;
-
 // Compute the name of the type as it should be stored in debuginfo. Does not do
 // any caching, i.e., calling the function twice with the same type will also do
 // the work twice. The `qualified` parameter only affects the first level of the
 // type name, further levels (i.e., type parameters) are always fully qualified.
-pub fn compute_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
+pub fn compute_debuginfo_type_name<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                              t: Ty<'tcx>,
                                              qualified: bool)
                                              -> String {
     let mut result = String::with_capacity(64);
     let mut visited = FxHashSet::default();
-    push_debuginfo_type_name(cx, t, qualified, &mut result, &mut visited);
+    push_debuginfo_type_name(tcx, t, qualified, &mut result, &mut visited);
     result
 }
 
 // Pushes the name of the type as it should be stored in debuginfo on the
 // `output` String. See also compute_debuginfo_type_name().
-pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
+pub fn push_debuginfo_type_name<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                           t: Ty<'tcx>,
                                           qualified: bool,
                                           output: &mut String,
@@ -33,7 +28,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
 
     // When targeting MSVC, emit C++ style type names for compatibility with
     // .natvis visualizers (and perhaps other existing native debuggers?)
-    let cpp_like_names = cx.sess().target.target.options.is_like_msvc;
+    let cpp_like_names = tcx.sess.target.target.options.is_like_msvc;
 
     match t.sty {
         ty::Bool => output.push_str("bool"),
@@ -43,15 +38,15 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         ty::Int(int_ty) => output.push_str(int_ty.ty_to_string()),
         ty::Uint(uint_ty) => output.push_str(uint_ty.ty_to_string()),
         ty::Float(float_ty) => output.push_str(float_ty.ty_to_string()),
-        ty::Foreign(def_id) => push_item_name(cx, def_id, qualified, output),
+        ty::Foreign(def_id) => push_item_name(tcx, def_id, qualified, output),
         ty::Adt(def, substs) => {
-            push_item_name(cx, def.did, qualified, output);
-            push_type_params(cx, substs, output, visited);
+            push_item_name(tcx, def.did, qualified, output);
+            push_type_params(tcx, substs, output, visited);
         },
         ty::Tuple(component_types) => {
             output.push('(');
             for &component_type in component_types {
-                push_debuginfo_type_name(cx, component_type, true, output, visited);
+                push_debuginfo_type_name(tcx, component_type, true, output, visited);
                 output.push_str(", ");
             }
             if !component_types.is_empty() {
@@ -69,7 +64,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
                 hir::MutMutable => output.push_str("mut "),
             }
 
-            push_debuginfo_type_name(cx, inner_type, true, output, visited);
+            push_debuginfo_type_name(tcx, inner_type, true, output, visited);
 
             if cpp_like_names {
                 output.push('*');
@@ -83,7 +78,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
                 output.push_str("mut ");
             }
 
-            push_debuginfo_type_name(cx, inner_type, true, output, visited);
+            push_debuginfo_type_name(tcx, inner_type, true, output, visited);
 
             if cpp_like_names {
                 output.push('*');
@@ -91,8 +86,8 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         },
         ty::Array(inner_type, len) => {
             output.push('[');
-            push_debuginfo_type_name(cx, inner_type, true, output, visited);
-            output.push_str(&format!("; {}", len.unwrap_usize(cx.tcx)));
+            push_debuginfo_type_name(tcx, inner_type, true, output, visited);
+            output.push_str(&format!("; {}", len.unwrap_usize(tcx)));
             output.push(']');
         },
         ty::Slice(inner_type) => {
@@ -102,7 +97,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
                 output.push('[');
             }
 
-            push_debuginfo_type_name(cx, inner_type, true, output, visited);
+            push_debuginfo_type_name(tcx, inner_type, true, output, visited);
 
             if cpp_like_names {
                 output.push('>');
@@ -112,12 +107,12 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         },
         ty::Dynamic(ref trait_data, ..) => {
             if let Some(principal) = trait_data.principal() {
-                let principal = cx.tcx.normalize_erasing_late_bound_regions(
+                let principal = tcx.normalize_erasing_late_bound_regions(
                     ty::ParamEnv::reveal_all(),
                     &principal,
                 );
-                push_item_name(cx, principal.def_id, false, output);
-                push_type_params(cx, principal.substs, output, visited);
+                push_item_name(tcx, principal.def_id, false, output);
+                push_type_params(tcx, principal.substs, output, visited);
             } else {
                 output.push_str("dyn '_");
             }
@@ -142,13 +137,13 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
             }
 
 
-            let sig = t.fn_sig(cx.tcx);
+            let sig = t.fn_sig(tcx);
             if sig.unsafety() == hir::Unsafety::Unsafe {
                 output.push_str("unsafe ");
             }
 
             let abi = sig.abi();
-            if abi != crate::abi::Abi::Rust {
+            if abi != rustc_target::spec::abi::Abi::Rust {
                 output.push_str("extern \"");
                 output.push_str(abi.name());
                 output.push_str("\" ");
@@ -156,10 +151,10 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
 
             output.push_str("fn(");
 
-            let sig = cx.tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
+            let sig = tcx.normalize_erasing_late_bound_regions(ty::ParamEnv::reveal_all(), &sig);
             if !sig.inputs().is_empty() {
                 for &parameter_type in sig.inputs() {
-                    push_debuginfo_type_name(cx, parameter_type, true, output, visited);
+                    push_debuginfo_type_name(tcx, parameter_type, true, output, visited);
                     output.push_str(", ");
                 }
                 output.pop();
@@ -178,7 +173,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
 
             if !sig.output().is_unit() {
                 output.push_str(" -> ");
-                push_debuginfo_type_name(cx, sig.output(), true, output, visited);
+                push_debuginfo_type_name(tcx, sig.output(), true, output, visited);
             }
 
 
@@ -213,18 +208,18 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         }
     }
 
-    fn push_item_name(cx: &CodegenCx<'_, '_>,
+    fn push_item_name(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                       def_id: DefId,
                       qualified: bool,
                       output: &mut String) {
         if qualified {
-            output.push_str(&cx.tcx.crate_name(def_id.krate).as_str());
-            for path_element in cx.tcx.def_path(def_id).data {
+            output.push_str(&tcx.crate_name(def_id.krate).as_str());
+            for path_element in tcx.def_path(def_id).data {
                 output.push_str("::");
                 output.push_str(&path_element.data.as_interned_str().as_str());
             }
         } else {
-            output.push_str(&cx.tcx.item_name(def_id).as_str());
+            output.push_str(&tcx.item_name(def_id).as_str());
         }
     }
 
@@ -233,7 +228,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
     // reconstructed for items from non-local crates. For local crates, this
     // would be possible but with inlining and LTO we have to use the least
     // common denominator - otherwise we would run into conflicts.
-    fn push_type_params<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
+    fn push_type_params<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                   substs: SubstsRef<'tcx>,
                                   output: &mut String,
                                   visited: &mut FxHashSet<Ty<'tcx>>) {
@@ -244,7 +239,7 @@ pub fn push_debuginfo_type_name<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         output.push('<');
 
         for type_parameter in substs.types() {
-            push_debuginfo_type_name(cx, type_parameter, true, output, visited);
+            push_debuginfo_type_name(tcx, type_parameter, true, output, visited);
             output.push_str(", ");
         }
 
diff --git a/src/librustc_codegen_ssa/lib.rs b/src/librustc_codegen_ssa/lib.rs
index 49e9f6fe38a..9d3d6ef8549 100644
--- a/src/librustc_codegen_ssa/lib.rs
+++ b/src/librustc_codegen_ssa/lib.rs
@@ -66,6 +66,7 @@ pub struct ModuleCodegen<M> {
     pub kind: ModuleKind,
 }
 
+pub const METADATA_FILENAME: &str = "rust.metadata.bin";
 pub const RLIB_BYTECODE_EXTENSION: &str = "bc.z";
 
 impl<M> ModuleCodegen<M> {