diff --git a/lib/Format/Format.cpp b/lib/Format/Format.cpp
index 040fb39..40e980f 100644
--- a/lib/Format/Format.cpp
+++ b/lib/Format/Format.cpp
@@ -1643,6 +1643,7 @@
   LangOptions LangOpts;
   LangOpts.CPlusPlus = 1;
   LangOpts.CPlusPlus11 = 1;
+  LangOpts.LineComment = 1;
   LangOpts.Bool = 1;
   LangOpts.ObjC1 = 1;
   LangOpts.ObjC2 = 1;