[clang] default clause replaced by otherwise clause for metadirective in OpenMP 5.2 (PR #128640)

[Urvi Rav via cfe-commits]

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@@ -1660,6 +1660,10 @@ def err_omp_expected_colon : Error<"missing ':' in %0">;
 def err_omp_missing_comma : Error< "missing ',' after %0">;
 def err_omp_expected_context_selector
     : Error<"expected valid context selector in %0">;
+def err_omp_unknown_clause
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ravurvi20 wrote:

Thanks for the suggestion. I've already used `err_omp_unexpected_clause` for the `OMPC_otherwise` case in OpenMP versions prior to 5.2, as suggested earlier. For `OMPC_unknown`, I'm using `err_omp_unknown_clause`, which aligns with the guidance to treat `OMPC_unknown` and `OMPC_otherwise` separately.

https://github.com/llvm/llvm-project/pull/128640