[clang] [Clang] Add [[clang::diagnose_specializations]] (PR #101469)

[Mital Ashok via cfe-commits]

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@@ -975,6 +975,15 @@ Query for this feature with ``__has_attribute(diagnose_if)``.
   }];
 }
 
+def DiagnoseSpecializationsDocs : Documentation {
+  let Category = DocCatDecl;
+  let Content = [{
+``clang::diagnose_specializations`` can be appied to class templates which
+should not be specialized by users. This is primarily used to diagnose user
+specializations of standard library type traits.
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MitalAshok wrote:

"applied to class or variable templates which should not be specialized."

I think "by users" should either be omitted or replaced with "by others"/"elsewhere" here, since this could be used by non-standard-library writers too. It's fine in the next sentence though.


https://github.com/llvm/llvm-project/pull/101469