[clang] [clang][Sema] Refine unused-member-function diagnostic message for constructors (PR #84515)

[Aaron Ballman via cfe-commits]

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@@ -402,7 +402,7 @@ def warn_unused_function : Warning<"unused function %0">,
   InGroup<UnusedFunction>, DefaultIgnore;
 def warn_unused_template : Warning<"unused %select{function|variable}0 template %1">,
   InGroup<UnusedTemplate>, DefaultIgnore;
-def warn_unused_member_function : Warning<"unused member function %0">,
+def warn_unused_member_function : Warning<"unused %select{constructor|member function %1}0">,
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AaronBallman wrote:

I would recommend using `%sub{select_special_member_kind}1` instead of manually spelling out constructor; see `note_member_synthesized_at` for an example of it being used.

https://github.com/llvm/llvm-project/pull/84515