diff --git a/lib/Basic/Targets.cpp b/lib/Basic/Targets.cpp
index 0552544..2ba09a9 100644
--- a/lib/Basic/Targets.cpp
+++ b/lib/Basic/Targets.cpp
@@ -1622,7 +1622,7 @@
     DefineStd(Builder, "WIN64", Opts);
     Builder.defineMacro("__MSVCRT__");
     Builder.defineMacro("__MINGW64__");
-    Builder.defineMacro("__declspec");
+    Builder.defineMacro("__declspec", "__declspec");
   }
 };
 } // end anonymous namespace