[clang] Fix Unintialised char *CommentLexer resulting in potential UB. (PR #210067)

[Hardik Kumar via cfe-commits]

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@@ -240,7 +240,7 @@ class Lexer {
 
   /// One past end pointer for the current comment.  For BCPL comments points
   /// to newline or BufferEnd, for C comments points to star in '*/'.
-  const char *CommentEnd;
+  const char *CommentEnd{nullptr};
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hardikxk wrote:

Got it thanks for the suggestion!

https://github.com/llvm/llvm-project/pull/210067