Index: cfe/trunk/lib/AST/ASTContext.cpp
===================================================================
--- cfe/trunk/lib/AST/ASTContext.cpp
+++ cfe/trunk/lib/AST/ASTContext.cpp
@@ -8077,7 +8077,8 @@
     // mismatch.
     if (LQuals.getCVRQualifiers() != RQuals.getCVRQualifiers() ||
         LQuals.getAddressSpace() != RQuals.getAddressSpace() ||
-        LQuals.getObjCLifetime() != RQuals.getObjCLifetime())
+        LQuals.getObjCLifetime() != RQuals.getObjCLifetime() ||
+        LQuals.hasUnaligned() != RQuals.hasUnaligned())
       return QualType();
 
     // Exactly one GC qualifier difference is allowed: __strong is
Index: cfe/trunk/test/Sema/unaligned-qualifier.c
===================================================================
--- cfe/trunk/test/Sema/unaligned-qualifier.c
+++ cfe/trunk/test/Sema/unaligned-qualifier.c
@@ -0,0 +1,4 @@
+// RUN: %clang_cc1 %s -verify -fsyntax-only -fms-extensions
+
+int __unaligned * p1; // expected-note {{previous definition is here}}
+int * p1; // expected-error {{redefinition of 'p1' with a different type: 'int *' vs '__unaligned int *'}}