[clang] Diagnose potential size confusion with VLA params [contd.] (PR #181550)

[Aaron Ballman via cfe-commits]

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@@ -1114,7 +1114,8 @@ def VexingParse : DiagGroup<"vexing-parse">;
 def VLAUseStaticAssert : DiagGroup<"vla-extension-static-assert">;
 def VLACxxExtension : DiagGroup<"vla-cxx-extension", [VLAUseStaticAssert]>;
 def VLAExtension : DiagGroup<"vla-extension", [VLACxxExtension]>;
-def VLA : DiagGroup<"vla", [VLAExtension]>;
+def VLASizeConfusion : DiagGroup<"vla-potential-size-confusion">;
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AaronBallman wrote:

I think separate flags probably makes sense; it may be the same confusion, but name lookup in structures is already sufficiently different than within a function prototype (parameters can refer to other parameters but fields cannot refer to other fields) that I think it likely makes sense to separate the flags. We would still want a parent group for them both so you can turn both on at the same time, but this would give users more control over where they see the diagnostics. That said, I don't have a strong opinion on it.

https://github.com/llvm/llvm-project/pull/181550