---

yaml
---
r: 24523
b: refs/heads/try2
c: db8d9dd
h: refs/heads/master
i:
  24521: 4e6c160
  24519: 48786d8
v: v3

Author: pcwalton

[refs]

@@ -5,7 +5,7 @@ refs/heads/snap-stage3: cd6f24f9d14ac90d167386a56e7a6ac1f0318195
 refs/heads/try: ffbe0e0e00374358b789b0037bcb3a577cd218be
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
-refs/heads/try2: 1c2843c8adb670570c6a18a06a5d1473b17afffb
+refs/heads/try2: db8d9ddcbb9741570a2724c227c824f5eda13ad1
 refs/heads/incoming: 05543fd04dfb3f63b453a331e239ceb1a9a219f9
 refs/heads/dist-snap: 2f32a1581f522e524009138b33b1c7049ced668d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596

branches/try2/src/rustc/middle/resolve3.rs

@@ -380,6 +380,17 @@ class Module {
     }
 }
 
+pure fn is_crate_root(module: @Module) -> bool {
+    alt module.def_id {
+        none => {
+            ret false;
+        }
+        some(def_id) => {
+            ret def_id.crate == 0 && def_id.node == 0;
+        }
+    }
+}
+
 // XXX: This is a workaround due to is_none in the standard library mistakenly
 // requiring a T:copy.
 
@@ -2802,6 +2813,20 @@ class Resolver {
             }
 
             item_fn(fn_decl, ty_params, block) {
+                // If this is the main function, we must record it in the
+                // session.
+                //
+                // For speed, we put the string comparison last in this chain
+                // of conditionals.
+
+                if !self.session.building_library &&
+                        is_none(self.session.main_fn) &&
+                        is_crate_root(self.current_module) &&
+                        str::eq(*item.ident, "main") {
+
+                    self.session.main_fn = some((item.id, item.span));
+                }
+
                 self.resolve_function(NormalRibKind,
                                       some(@fn_decl),
                                       HasTypeParameters(&ty_params,