diff --git a/include/llvm/TypeSymbolTable.h b/include/llvm/TypeSymbolTable.h
index 26b1dbf2df4..55b8b7a3d9a 100644
--- a/include/llvm/TypeSymbolTable.h
+++ b/include/llvm/TypeSymbolTable.h
@@ -16,12 +16,11 @@
 
 #include "llvm/Type.h"
 #include "llvm/ADT/StringRef.h"
+#include "llvm/System/DataTypes.h"
 #include <map>
 
 namespace llvm {
 
-class StringRef;
-
 /// This class provides a symbol table of name/type pairs with operations to
 /// support constructing, searching and iterating over the symbol table. The
 /// class derives from AbstractTypeUser so that the contents of the symbol