Two null Decl*'s don't refer to the same declaration, because they

don't refer to anything. Amusingly, we were relying on this in one
place. Thanks to Chandler for noticing the weirdness in
declaresSameEntity.

llvm-svn: 146659

2 files changed, 7 insertions, 6 deletions

diff --git a/clang/include/clang/AST/DeclBase.h b/clang/include/clang/AST/DeclBase.h
index b0534b82804..ecd7762468e 100644
--- a/clang/include/clang/AST/DeclBase.h
+++ b/clang/include/clang/AST/DeclBase.h
@@ -762,12 +762,12 @@ protected:
 
 /// \brief Determine whether two declarations declare the same entity.
 inline bool declaresSameEntity(const Decl *D1, const Decl *D2) {
-  if (D1 == D2)
-    return true;
-  
   if (!D1 || !D2)
     return false;
   
+  if (D1 == D2)
+    return true;
+  
   return D1->getCanonicalDecl() == D2->getCanonicalDecl();
 }
   
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index d0d1484dd04..cf8df57eb3a 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -2262,7 +2262,7 @@ void Sema::HandleFunctionTypeMismatch(PartialDiagnostic &PDiag,
 }
 
 /// FunctionArgTypesAreEqual - This routine checks two function proto types
-/// for equlity of their argument types. Caller has already checked that
+/// for equality of their argument types. Caller has already checked that
 /// they have same number of arguments. This routine assumes that Objective-C
 /// pointer types which only differ in their protocol qualifiers are equal.
 /// If the parameters are different, ArgPos will have the the parameter index
@@ -2300,8 +2300,9 @@ bool Sema::FunctionArgTypesAreEqual(const FunctionProtoType *OldType,
                  ToType->getAs<ObjCObjectPointerType>()) {
         if (const ObjCObjectPointerType *PTFr =
               FromType->getAs<ObjCObjectPointerType>())
-          if (declaresSameEntity(PTTo->getInterfaceDecl(), 
-                                 PTFr->getInterfaceDecl()))
+          if (Context.hasSameUnqualifiedType(
+                PTTo->getObjectType()->getBaseType(),
+                PTFr->getObjectType()->getBaseType()))
             continue;
       }
       if (ArgPos) *ArgPos = O - OldType->arg_type_begin();