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

[Aaron Ballman 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 applied to class or variable
+templates which should not be specialized by users. This is primarily used to
----------------
AaronBallman wrote:

```suggestion
templates which should not be explicitly specialized by users. This is primarily used to
```

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