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

[Krzysztof Parzyszek via cfe-commits]

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@@ -1657,6 +1657,10 @@ 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
+    : Error<"unknown clause '%0' in %1">;
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kparzysz wrote:

We already have a message for a wrong clause for a directive: `err_omp_unexpected_clause`.  This does not apply when we have some unknown string where a clause is expected.

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