From a4d88dacc9dd70547ece3dcc65fbc61a8fcfa91d Mon Sep 17 00:00:00 2001
From: Brian Anderson <banderson@mozilla.com>
Date: Fri, 17 Jun 2011 11:23:32 -0700
Subject: rustc: Fail to unify if two ty_vars don't unify

Closes #500
---
 src/comp/middle/ty.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

(limited to 'src/comp')

diff --git a/src/comp/middle/ty.rs b/src/comp/middle/ty.rs
index c8050eb1bc9..deaf925f0b8 100644
--- a/src/comp/middle/ty.rs
+++ b/src/comp/middle/ty.rs
@@ -1943,7 +1943,12 @@ mod unify {
                 alt (struct(cx.tcx, expected)) {
                     case (ty::ty_var(?expected_id)) {
                         auto expected_n = expected_id as uint;
-                        union(cx, expected_n, actual_n);
+                        alt(union(cx, expected_n, actual_n)) {
+                            case (unres_ok) { /* fall through */ }
+                            case (unres_err(?t_e)) {
+                                ret ures_err(t_e);
+                            }
+                        }
                     }
                     case (_) {
 
-- 
cgit 1.4.1-3-g733a5