diff --git a/lib/IR/ProfileSummary.cpp b/lib/IR/ProfileSummary.cpp
index fbd2fa5ed8a..ac6bcd9fe3a 100644
--- a/lib/IR/ProfileSummary.cpp
+++ b/lib/IR/ProfileSummary.cpp
@@ -18,6 +18,7 @@
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/Type.h"
 #include "llvm/Support/Casting.h"
+#include "llvm/Support/Format.h"
 
 using namespace llvm;