r216695 - Don't load ill-formed AmbiguityKind in Sema::Lookup.

[Alexey Samsonov]

Author: samsonov
Date: Thu Aug 28 18:17:55 2014
New Revision: 216695

URL: http://llvm.org/viewvc/llvm-project?rev=216695&view=rev
Log:
Don't load ill-formed AmbiguityKind in Sema::Lookup.

This bug was reported by UBSan.

Modified:
    cfe/trunk/include/clang/Sema/Lookup.h

Modified: cfe/trunk/include/clang/Sema/Lookup.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Sema/Lookup.h?rev=216695&r1=216694&r2=216695&view=diff
==============================================================================
--- cfe/trunk/include/clang/Sema/Lookup.h (original)
+++ cfe/trunk/include/clang/Sema/Lookup.h Thu Aug 28 18:17:55 2014
@@ -424,13 +424,19 @@ public:
         Paths = nullptr;
       }
     } else {
-      AmbiguityKind SavedAK = Ambiguity;
+      AmbiguityKind SavedAK;
+      bool WasAmbiguous = false;
+      if (ResultKind == Ambiguous) {
+        SavedAK = Ambiguity;
+        WasAmbiguous = true;
+      }
       ResultKind = Found;
       resolveKind();
 
       // If we didn't make the lookup unambiguous, restore the old
       // ambiguity kind.
       if (ResultKind == Ambiguous) {
+        assert(WasAmbiguous);
         Ambiguity = SavedAK;
       } else if (Paths) {
         deletePaths(Paths);