diff --git a/third_party/LLVM/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp b/third_party/LLVM/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
index f98d5e3..4156074 100644
--- a/third_party/LLVM/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
+++ b/third_party/LLVM/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
@@ -35,6 +35,10 @@
 #define GET_SUBTARGETINFO_MC_DESC
 #include "X86GenSubtargetInfo.inc"
 
+#ifdef _MSC_VER
+#include <intrin.h>
+#endif
+
 using namespace llvm;