diff --git a/clang/lib/Frontend/InitHeaderSearch.cpp b/clang/lib/Frontend/InitHeaderSearch.cpp
index d2890f0..d2edc94 100644
--- a/clang/lib/Frontend/InitHeaderSearch.cpp
+++ b/clang/lib/Frontend/InitHeaderSearch.cpp
@@ -472,7 +472,8 @@
 
   case llvm::Triple::Win32:
     if (triple.getEnvironment() == llvm::Triple::MSVC ||
-        triple.getEnvironment() == llvm::Triple::Itanium)
+        triple.getEnvironment() == llvm::Triple::Itanium ||
+        triple.getObjectFormat() == llvm::Triple::MachO)
       return;
     break;
   }