diff --git a/Lex/ScratchBuffer.cpp b/Lex/ScratchBuffer.cpp
index bf0d88e..99fbdf7 100644
--- a/Lex/ScratchBuffer.cpp
+++ b/Lex/ScratchBuffer.cpp
@@ -14,6 +14,7 @@
 #include "clang/Lex/ScratchBuffer.h"
 #include "clang/Basic/SourceManager.h"
 #include "llvm/Support/MemoryBuffer.h"
+#include <cstring>
 using namespace clang;
 
 // ScratchBufSize - The size of each chunk of scratch memory.  Slightly less