diff --git a/clang/include/clang/Basic/DiagnosticSemaKinds.td b/clang/include/clang/Basic/DiagnosticSemaKinds.td
index 53372bb62739..9b6eaf3c18df 100644
--- a/clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1178,6 +1178,8 @@ def warn_attribute_void_function_method : Warning<
   "%select{functions|Objective-C method}1 without return value">;
 def warn_attribute_weak_on_field : Warning<
   "__weak attribute cannot be specified on a field declaration">;
+def warn_gc_attribute_weak_on_local : Warning<
+  "Objective-C GC does not allow weak variables on the stack">;
 def warn_attribute_weak_on_local : Warning<
   "__weak attribute cannot be specified on an automatic variable">;
 def warn_weak_identifier_undeclared : Warning<
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index e1872c2d7dbf..1adc8bd0ed58 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -3850,8 +3850,12 @@ void Sema::CheckVariableDeclaration(VarDecl *NewVD,
   }
 
   if (NewVD->hasLocalStorage() && T.isObjCGCWeak()
-      && !NewVD->hasAttr<BlocksAttr>())
-    Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
+      && !NewVD->hasAttr<BlocksAttr>()) {
+    if (getLangOptions().getGCMode() != LangOptions::NonGC)
+      Diag(NewVD->getLocation(), diag::warn_gc_attribute_weak_on_local);
+    else
+      Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local);
+  }
   
   bool isVM = T->isVariablyModifiedType();
   if (isVM || NewVD->hasAttr<CleanupAttr>() ||
diff --git a/clang/test/SemaObjC/objc2-warn-weak-decl.m b/clang/test/SemaObjC/objc2-warn-weak-decl.m
index 22a3fca91ba5..b85f7682a96b 100644
--- a/clang/test/SemaObjC/objc2-warn-weak-decl.m
+++ b/clang/test/SemaObjC/objc2-warn-weak-decl.m
@@ -6,6 +6,6 @@ struct S {
 
 int main ()
 {
-  __weak id  local;  // expected-warning {{__weak attribute cannot be specified on an automatic variable}}
+  __weak id  local;  // expected-warning {{Objective-C GC does not allow weak variables on the stack}}
 }