diff --git a/lib/Frontend/InitPreprocessor.cpp b/lib/Frontend/InitPreprocessor.cpp
index 6b93c697d9b1e04af64bf1a16b119d4f746e030d..1e71b20f473780ed10ae5ed17558890f0b509df6 100644
--- a/lib/Frontend/InitPreprocessor.cpp
+++ b/lib/Frontend/InitPreprocessor.cpp
@@ -512,7 +512,10 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
   Builder.defineMacro("__clang_major__", TOSTR(CLANG_VERSION_MAJOR));
   Builder.defineMacro("__clang_minor__", TOSTR(CLANG_VERSION_MINOR));
 #ifdef CLANG_VERSION_PATCHLEVEL
-  Builder.defineMacro("__clang_patchlevel__", TOSTR(CLANG_VERSION_PATCHLEVEL));
+  // Builder.defineMacro("__clang_patchlevel__", TOSTR(CLANG_VERSION_PATCHLEVEL));
+  // Dirty, we want cmake to use the original patchlevel (for install),
+  // but we want the programmer to know there is some extensions
+  Builder.defineMacro("__clang_patchlevel__", "1");
 #else
   Builder.defineMacro("__clang_patchlevel__", "0");
 #endif