[clang] [clang] Improve `_Alignas` on a `struct` declaration diagnostic (PR #65638)

[Aaron Ballman via cfe-commits]

================
@@ -264,6 +264,11 @@ Attribute Changes in Clang
   supports but that are never the result of default argument promotion, such as
   ``float``. (`#59824: <https://github.com/llvm/llvm-project/issues/59824>`_)
 
+- Clang now warns you that the ``_Alignas`` attribute on declaration specifiers
+  is ignored, changed from the former incorrect suggestion to move it past
+  declaration specifiers.
+
----------------
AaronBallman wrote:

```suggestion
  declaration specifiers.
  (#58637 <https://github.com/llvm/llvm-project/issues/58637>`_)
```

https://github.com/llvm/llvm-project/pull/65638