---

yaml
---
r: 60186
b: refs/heads/master
c: f04eb37
h: refs/heads/master
v: v3

Author: bors

[refs]

@@ -1,5 +1,5 @@
 ---
-refs/heads/master: 3e106cf2c2556be6bbcd9a93e5ef2a73b98f0e7a
+refs/heads/master: f04eb37c7ea19bbd2cff12d15816873e0a46fc86
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 2d28d645422c1617be58c8ca7ad9a457264ca850
 refs/heads/try: c50a9d5b664478e533ba1d1d353213d70c8ad589

trunk/src/librustc/middle/resolve.rs

@@ -64,7 +64,7 @@ use syntax::attr::{attr_metas, contains_name, attrs_contains_name};
 use syntax::parse::token::ident_interner;
 use syntax::parse::token::special_idents;
 use syntax::print::pprust::path_to_str;
-use syntax::codemap::{span, dummy_sp};
+use syntax::codemap::{span, dummy_sp, BytePos};
 use syntax::visit::{default_visitor, mk_vt, Visitor, visit_block};
 use syntax::visit::{visit_crate, visit_expr, visit_expr_opt};
 use syntax::visit::{visit_foreign_item, visit_item};
@@ -2482,6 +2482,16 @@ pub impl Resolver {
                                               TypeNS,
                                               name_search_type) {
                 Failed => {
+                    let segment_name = self.session.str_of(name);
+                    let module_name = self.module_to_str(search_module);
+                    if module_name == ~"???" {
+                        self.session.span_err(span {lo: span.lo, hi: span.lo +
+                                              BytePos(str::len(*segment_name)), expn_info:
+                                              span.expn_info}, fmt!("unresolved import. maybe \
+                                                                    a missing 'extern mod %s'?",
+                                                                    *segment_name));
+                        return Failed;
+                    }
                     self.session.span_err(span, ~"unresolved name");
                     return Failed;
                 }

trunk/src/test/compile-fail/issue-1697.rs

@@ -10,7 +10,7 @@
 
 // Testing that we don't fail abnormally after hitting the errors
 
-use unresolved::*; //~ ERROR unresolved name
+use unresolved::*; //~ ERROR unresolved import. maybe a missing
 //~^ ERROR failed to resolve import
 
 fn main() {

trunk/src/test/compile-fail/unresolved-import.rs

@@ -0,0 +1,12 @@
+// 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.
+
+use foo::bar; //~ ERROR unresolved import. maybe a missing
+              //~^ ERROR failed to resolve import