diff --git a/lib/Lex/PPExpressions.cpp b/lib/Lex/PPExpressions.cpp
index a74396c..b54dfe0 100644
--- a/lib/Lex/PPExpressions.cpp
+++ b/lib/Lex/PPExpressions.cpp
@@ -228,7 +228,7 @@
       return true;  // A diagnostic was already emitted.
 
     // Character literals are always int or wchar_t, expand to intmax_t.
-    TargetInfo &TI = PP.getTargetInfo();
+    const TargetInfo &TI = PP.getTargetInfo();
     unsigned NumBits;
     if (Literal.isMultiChar())
       NumBits = TI.getIntWidth();