[clang] [clang][Sema] Add diagnostic note for reference of function-like macros requiring without parentheses (PR #123495)

[via cfe-commits]

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@@ -2509,6 +2509,20 @@ bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
     DC = DC->getLookupParent();
   }
 
+  // Check whether a similar function-like macro exists and suggest it
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StarOne01 wrote:

I did try it, but in this case the function returns [here itself](https://github.com/llvm/llvm-project/blob/main/clang%2Flib%2FSema%2FSemaExpr.cpp#L2525-L2526) which is before giving up, maybe i could put the note inside this conditional?

https://github.com/llvm/llvm-project/pull/123495