[clang] [C23][Parser] Diagnostic for attribute declaration where statement is required (PR #146224)

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@@ -15,18 +15,19 @@ void f(int n) {
       return;
     }
   case 2:
+    // FIXME: Should we emit an error {{fallthrough annotation does not directly precede switch label}}?
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yronglin wrote:

Hmm, this because I originally set the new diagnostic's severity to `Error`, which will interrupt the warning static analysis based warnings.
https://github.com/llvm/llvm-project/blob/da01257c3a16b728718f9bde8bbe435678d96fd8/clang/lib/Sema/AnalysisBasedWarnings.cpp#L2632-L2633

I have changed the severity to `Warning` now.



https://github.com/llvm/llvm-project/pull/146224