diff --git a/include/clang/AST/CommentLexer.h b/include/clang/AST/CommentLexer.h
index 1ff7937..f167934 100644
--- a/include/clang/AST/CommentLexer.h
+++ b/include/clang/AST/CommentLexer.h
@@ -509,7 +509,7 @@
       } else
         Error = true;
     }
-    char C;
+    char C = '\0';
     while (!Error && !isEnd()) {
       C = peek();
       WordText.push_back(C);