[clang] [OpenMP][Clang] Handle unsupported inscan modifier for generic types (PR #79431)

[Alexey Bataev via cfe-commits]

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@@ -19520,6 +19520,13 @@ static bool actOnOMPReductionKindClause(
   bool FirstIter = true;
   for (Expr *RefExpr : VarList) {
     assert(RefExpr && "nullptr expr in OpenMP reduction clause.");
+    if (ClauseKind == OMPC_reduction &&
+        RD.RedModifier == OMPC_REDUCTION_inscan && RefExpr->isTypeDependent()) {
+      S.Diag(RefExpr->getExprLoc(),
+             diag::err_omp_inscan_reduction_on_template_type);
+      continue;
+    }
+
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alexey-bataev wrote:

This is definetely wrong, templates should be supported

https://github.com/llvm/llvm-project/pull/79431