Use cast<> + OpaquePtr.getAs<Decl> to add extra checking of our assumptions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@100496 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaObjCProperty.cpp b/lib/Sema/SemaObjCProperty.cpp
index 6057504..cda1f0b 100644
--- a/lib/Sema/SemaObjCProperty.cpp
+++ b/lib/Sema/SemaObjCProperty.cpp
@@ -160,7 +160,7 @@
                       PIDecl->getSetterName(),
                       DeclPtrTy::make(CCPrimary), isOverridingProperty,
                       MethodImplKind);
-      PIDecl = ProtocolPtrTy.getAs<ObjCPropertyDecl>();
+      PIDecl = cast<ObjCPropertyDecl>(ProtocolPtrTy.getAs<Decl>());
     }
     PIDecl->makeitReadWriteAttribute();
     if (Attributes & ObjCDeclSpec::DQ_PR_retain)
@@ -281,7 +281,8 @@
                                             DeclPtrTy ClassCatImpDecl,
                                             IdentifierInfo *PropertyId,
                                             IdentifierInfo *PropertyIvar) {
-  ObjCContainerDecl *ClassImpDecl = ClassCatImpDecl.getAs<ObjCContainerDecl>();
+  ObjCContainerDecl *ClassImpDecl =
+    cast_or_null<ObjCContainerDecl>(ClassCatImpDecl.getAs<Decl>());
   // Make sure we have a context for the property implementation declaration.
   if (!ClassImpDecl) {
     Diag(AtLoc, diag::error_missing_property_context);