diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index c89403cd0648..71bb4fcf684a 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -504,6 +504,7 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
            .Case("cxx_rtti", LangOpts.RTTI)
            .Case("cxx_static_assert", LangOpts.CPlusPlus0x)
            .Case("objc_nonfragile_abi", LangOpts.ObjCNonFragileABI)
+           .Case("objc_weak_class", LangOpts.ObjCNonFragileABI)
          //.Case("cxx_concepts", false)
          //.Case("cxx_lambdas", false)
          //.Case("cxx_nullptr", false)