diff --git a/llvm/include/llvm/Support/Compiler.h b/llvm/include/llvm/Support/Compiler.h
index 14b55c147fe8..9c5e7ecbae42 100644
--- a/llvm/include/llvm/Support/Compiler.h
+++ b/llvm/include/llvm/Support/Compiler.h
@@ -61,7 +61,7 @@
 #define LLVM_ATTRIBUTE_READONLY
 #endif
 
-#if (__GNUC__ >= 4)
+#if (__GNUC__ >= 4) && !defined(__MINGW32__) && !defined(__CYGWIN__)
 #define LLVM_ATTRIBUTE_WEAK __attribute__((__weak__))
 #else
 #define LLVM_ATTRIBUTE_WEAK