[clang] [SYCL] Basic diagnostics for the sycl_kernel_entry_point attribute. (PR #120327)

[Tom Honermann via cfe-commits]

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@@ -1550,6 +1550,8 @@ NamedDecl *Sema::ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
     IdResolver.AddDecl(Param);
   }
 
+  ProcessDeclAttributes(S, Param, D);
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tahonermann wrote:

Thanks, @AaronBallman.

See also [P3324 (Attributes for namespace aliases, template parameters, and lambda captures)](https://wg21.link/p3324) which would clarify the situation from the perspective of the C++ standard.

What I'll do for now is to move this change to a separate PR and annotate the impacted test (`bad18()` in `clang/test/SemaSYCL/sycl-kernel-entry-point-attr-appertainment.cpp`) with FIXME comments. We can then pursue any additional changes needed via that other PR at our leisure.

https://github.com/llvm/llvm-project/pull/120327