[clang] [Clang] Ensure child classes export inherited constructors from base classes (PR #182706)

[Hans Wennborg via cfe-commits]

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@@ -3935,6 +3935,11 @@ def warn_dllexport_on_decl_ignored : Warning<
   InGroup<IgnoredAttributes>;
 def note_dllexport_on_decl : Note<
   "'dllexport' attribute on the declaration is ignored">;
+def warn_dllexport_inherited_ctor_unsupported : Warning<
+  "exporting inherited constructor is not yet supported; "
+  "'dllexport' ignored on inherited constructor with "
+  "%select{variadic arguments|callee-cleanup parameters}0">,
+  InGroup<IgnoredAttributes>;
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zmodem wrote:

This is firing a lot, and is not actionable for users.

I'm not really sure what to do about it though. The best thing would of course be to fix the thunks, but in the meantime getting a separate warning flag for this so it can be suppressed would be good.

https://github.com/llvm/llvm-project/pull/182706