Speculative fix for Windows build after r220932

[oota-llvm.git] / lib / Support / Windows / Threading.inc

diff --git a/lib/Support/Windows/Threading.inc b/lib/Support/Windows/Threading.inc
index 099c6b28bf6fc1c7309ea5a047c6f1957dcf8c90..41fdd981fd6e71816e2d48d20f964665c28b8f4c 100644 (file)
--- a/lib/Support/Windows/Threading.inc
+++ b/lib/Support/Windows/Threading.inc
@@ -1,5 +1,10 @@
 #include <winbase.h>
 
+#ifdef MemoryFence
+// WinNT.h seems to define a MemoryFence macro.
+#undef MemoryFence
+#endif
+
 void llvm::call_once(once_flag &flag, void (*fptr)(void)) {
   while (flag != Done) {
     if (flag == Wait) {