Inline constants across crates.

7 files changed, 133 insertions, 26 deletions

diff --git a/src/librustc/metadata/encoder.rs b/src/librustc/metadata/encoder.rs
index 3d81b01a0c9..67d25637093 100644
--- a/src/librustc/metadata/encoder.rs
+++ b/src/librustc/metadata/encoder.rs
@@ -616,7 +616,7 @@ fn encode_info_for_item(ecx: @EncodeContext, ebml_w: writer::Encoder,
     let must_write =
         match item.node {
           item_enum(_, _) | item_impl(*) | item_trait(*) | item_struct(*) |
-          item_mod(*) | item_foreign_mod(*) => true,
+          item_mod(*) | item_foreign_mod(*) | item_const(*) => true,
           _ => false
         };
     if !must_write && !reachable(ecx, item.id) { return; }
@@ -639,6 +639,7 @@ fn encode_info_for_item(ecx: @EncodeContext, ebml_w: writer::Encoder,
         encode_type(ecx, ebml_w, node_id_to_type(tcx, item.id));
         encode_symbol(ecx, ebml_w, item.id);
         encode_path(ecx, ebml_w, path, ast_map::path_name(item.ident));
+        (ecx.encode_inlined_item)(ecx, ebml_w, path, ii_item(item));
         ebml_w.end_tag();
       }
       item_fn(_, purity, ref generics, _) => {
diff --git a/src/librustc/middle/check_const.rs b/src/librustc/middle/check_const.rs
index 2e528b4c0df..58099574126 100644
--- a/src/librustc/middle/check_const.rs
+++ b/src/librustc/middle/check_const.rs
@@ -124,17 +124,11 @@ pub fn check_expr(sess: Session,
                               items without type parameters");
             }
             match def_map.find(&e.id) {
-                Some(def_variant(_, _)) |
-                Some(def_struct(_)) => { }
+              Some(def_const(_)) |
+              Some(def_fn(_, _)) |
+              Some(def_variant(_, _)) |
+              Some(def_struct(_)) => { }
 
-                Some(def_const(def_id)) |
-                Some(def_fn(def_id, _)) => {
-                if !ast_util::is_local(def_id) {
-                    sess.span_err(
-                        e.span, ~"paths in constants may only refer to \
-                                 crate-local constants or functions");
-                }
-              }
               Some(def) => {
                 debug!("(checking const) found bad def: %?", def);
                 sess.span_err(
@@ -246,11 +240,13 @@ pub fn check_item_recursion(sess: Session,
           expr_path(*) => {
             match env.def_map.find(&e.id) {
               Some(def_const(def_id)) => {
-                match env.ast_map.get(&def_id.node) {
-                  ast_map::node_item(it, _) => {
-                    (v.visit_item)(it, env, v);
+                if ast_util::is_local(def_id) {
+                  match env.ast_map.get(&def_id.node) {
+                    ast_map::node_item(it, _) => {
+                      (v.visit_item)(it, env, v);
+                    }
+                    _ => fail!(~"const not bound to an item")
                   }
-                  _ => fail!(~"const not bound to an item")
                 }
               }
               _ => ()
diff --git a/src/librustc/middle/trans/consts.rs b/src/librustc/middle/trans/consts.rs
index 0dca64ee8d3..1117d9b9bf8 100644
--- a/src/librustc/middle/trans/consts.rs
+++ b/src/librustc/middle/trans/consts.rs
@@ -11,6 +11,7 @@
 use core::prelude::*;
 
 use lib::llvm::{llvm, ValueRef, TypeRef, Bool, True, False};
+use metadata::csearch;
 use middle::const_eval;
 use middle::trans::adt;
 use middle::trans::base;
@@ -18,6 +19,7 @@ use middle::trans::base::get_insn_ctxt;
 use middle::trans::common::*;
 use middle::trans::consts;
 use middle::trans::expr;
+use middle::trans::inline;
 use middle::trans::machine;
 use middle::trans::type_of;
 use middle::ty;
@@ -121,10 +123,12 @@ pub fn const_autoderef(cx: @CrateContext, ty: ty::t, v: ValueRef)
 }
 
 pub fn get_const_val(cx: @CrateContext, def_id: ast::def_id) -> ValueRef {
-    if !ast_util::is_local(def_id) {
-        cx.tcx.sess.bug(~"cross-crate constants");
-    }
-    if !cx.const_values.contains_key(&def_id.node) {
+    let mut def_id = def_id;
+    if !ast_util::is_local(def_id) ||
+       !cx.const_values.contains_key(&def_id.node) {
+        if !ast_util::is_local(def_id) {
+            def_id = inline::maybe_instantiate_inline(cx, def_id, true);
+        }
         match cx.tcx.items.get(&def_id.node) {
             ast_map::node_item(@ast::item {
                 node: ast::item_const(_, subexpr), _
@@ -419,8 +423,13 @@ fn const_expr_unchecked(cx: @CrateContext, e: @ast::expr) -> ValueRef {
             assert pth.types.len() == 0;
             match cx.tcx.def_map.find(&e.id) {
                 Some(ast::def_fn(def_id, _purity)) => {
-                    assert ast_util::is_local(def_id);
-                    let f = base::get_item_val(cx, def_id.node);
+                    let f = if !ast_util::is_local(def_id) {
+                        let ty = csearch::get_type(cx.tcx, def_id).ty;
+                        base::trans_external_path(cx, def_id, ty)
+                    } else {
+                        assert ast_util::is_local(def_id);
+                        base::get_item_val(cx, def_id.node)
+                    };
                     let ety = ty::expr_ty_adjusted(cx.tcx, e);
                     match ty::get(ety).sty {
                         ty::ty_bare_fn(*) | ty::ty_ptr(*) => {
diff --git a/src/librustc/middle/trans/expr.rs b/src/librustc/middle/trans/expr.rs
index 1dae9fccc62..5fb07d6e7d8 100644
--- a/src/librustc/middle/trans/expr.rs
+++ b/src/librustc/middle/trans/expr.rs
@@ -138,6 +138,7 @@ use middle::trans::consts;
 use middle::trans::controlflow;
 use middle::trans::datum::*;
 use middle::trans::debuginfo;
+use middle::trans::inline;
 use middle::trans::machine;
 use middle::trans::meth;
 use middle::trans::tvec;
@@ -984,15 +985,54 @@ fn trans_lvalue_unadjusted(bcx: block, expr: @ast::expr) -> DatumBlock {
         match def {
             ast::def_const(did) => {
                 let const_ty = expr_ty(bcx, ref_expr);
-                let val = if did.crate == ast::local_crate {
+
+                #[cfg(stage0)]
+                fn get_did(_ccx: @CrateContext, did: ast::def_id)
+                    -> ast::def_id {
+                    did
+                }
+
+                #[cfg(stage1)]
+                #[cfg(stage2)]
+                #[cfg(stage3)]
+                fn get_did(ccx: @CrateContext, did: ast::def_id)
+                    -> ast::def_id {
+                    if did.crate != ast::local_crate {
+                        inline::maybe_instantiate_inline(ccx, did, true)
+                    } else {
+                        did
+                    }
+                }
+
+                #[cfg(stage0)]
+                fn get_val(bcx: block, did: ast::def_id, const_ty: ty::t)
+                    -> ValueRef {
+                    let ccx = bcx.ccx();
+                    if did.crate == ast::local_crate {
+                        // The LLVM global has the type of its initializer,
+                        // which may not be equal to the enum's type for
+                        // non-C-like enums.
+                        PointerCast(bcx, base::get_item_val(ccx, did.node),
+                                    T_ptr(type_of(bcx.ccx(), const_ty)))
+                    } else {
+                        base::trans_external_path(ccx, did, const_ty)
+                    }
+                }
+
+                #[cfg(stage1)]
+                #[cfg(stage2)]
+                #[cfg(stage3)]
+                fn get_val(bcx: block, did: ast::def_id, const_ty: ty::t)
+                    -> ValueRef {
                     // The LLVM global has the type of its initializer,
                     // which may not be equal to the enum's type for
                     // non-C-like enums.
-                    PointerCast(bcx, base::get_item_val(ccx, did.node),
+                    PointerCast(bcx, base::get_item_val(bcx.ccx(), did.node),
                                 T_ptr(type_of(bcx.ccx(), const_ty)))
-                } else {
-                    base::trans_external_path(ccx, did, const_ty)
-                };
+                }
+
+                let did = get_did(ccx, did);
+                let val = get_val(bcx, did, const_ty);
                 DatumBlock {
                     bcx: bcx,
                     datum: Datum {val: val,
diff --git a/src/test/auxiliary/cci_const.rs b/src/test/auxiliary/cci_const.rs
new file mode 100644
index 00000000000..b2dd0cc8e58
--- /dev/null
+++ b/src/test/auxiliary/cci_const.rs
@@ -0,0 +1,16 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+pub extern fn bar() {
+}
+
+pub const foopy: &static/str = "hi there";
+pub const uint_val: uint = 12;
+pub const uint_expr: uint = (1 << uint_val) - 1;
diff --git a/src/test/run-pass/const-cross-crate-const.rs b/src/test/run-pass/const-cross-crate-const.rs
new file mode 100644
index 00000000000..eb3c482737c
--- /dev/null
+++ b/src/test/run-pass/const-cross-crate-const.rs
@@ -0,0 +1,25 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// xfail-fast
+// aux-build:cci_const.rs
+
+extern mod cci_const;
+const foo: &static/str = cci_const::foopy;
+const a: uint = cci_const::uint_val;
+const b: uint = cci_const::uint_expr + 5;
+
+fn main() {
+    assert a == 12;
+    let foo2 = a;
+    assert foo2 == cci_const::uint_val;
+    assert b == cci_const::uint_expr + 5;
+    assert foo == cci_const::foopy;
+}
diff --git a/src/test/run-pass/const-cross-crate-extern.rs b/src/test/run-pass/const-cross-crate-extern.rs
new file mode 100644
index 00000000000..e86118f3c43
--- /dev/null
+++ b/src/test/run-pass/const-cross-crate-extern.rs
@@ -0,0 +1,20 @@
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+// xfail-fast
+// aux-build:cci_const.rs
+
+extern mod cci_const;
+use cci_const::bar;
+const foo: *u8 = bar;
+
+fn main() {
+    assert foo == cci_const::bar;
+}