From 468786e36d5ab35afb54b60bc1d6147ba0db8733 Mon Sep 17 00:00:00 2001
From: Tim Chevalier <chevalier@alum.wellesley.edu>
Date: Thu, 2 Jun 2011 17:48:40 -0700
Subject: [PATCH] Fix unification bug

Hello from SFO Terminal 3!

unify_fn_common had the expected and actual types reversed in one
place. This was causing the type of an occurence of a function f
with type fn(int) -> T to be set to fn(_|_) -> T at a call site like
f(fail); I think this was also making some of the type error messages
come out backwards, but I haven't checked.

Also: ty_bot does not contain pointers
---
 src/comp/middle/ty.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/comp/middle/ty.rs b/src/comp/middle/ty.rs
index f936d7513e5c..5f0c9a90362a 100644
--- a/src/comp/middle/ty.rs
+++ b/src/comp/middle/ty.rs
@@ -981,6 +981,7 @@ fn type_has_pointers(&ctxt cx, &t ty) -> bool {
     alt (struct(cx, ty)) {
         // scalar types
         case (ty_nil) { ret false; }
+        case (ty_bot) { ret false; }
         case (ty_bool) { ret false; }
         case (ty_int) { ret false; }
         case (ty_float) { ret false; }
@@ -2049,7 +2050,7 @@ mod unify {
                 result_mode = expected_input.mode;
             }
 
-            auto result = unify_step(cx, actual_input.ty, expected_input.ty);
+            auto result = unify_step(cx, expected_input.ty, actual_input.ty);
 
             alt (result) {
                 case (ures_ok(?rty)) {