diff --git a/llvm/lib/Archive/ArchiveReader.cpp b/llvm/lib/Archive/ArchiveReader.cpp
index 8d607f0..b07e884 100644
--- a/llvm/lib/Archive/ArchiveReader.cpp
+++ b/llvm/lib/Archive/ArchiveReader.cpp
@@ -15,6 +15,7 @@
 #include "llvm/Bitcode/ReaderWriter.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Module.h"
+#include <cstdlib>
 #include <memory>
 using namespace llvm;