[clang] [Clang] Fix false-positive fallthrough warning (#230802) (PR #234848)

[Adinesh Reddy via cfe-commits]

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@@ -255,6 +255,30 @@ int fallthrough_covered_enums(Enum e) {
 
 // Fallthrough annotations in local classes used to generate "fallthrough
 // annotation does not directly precede switch label" warning.
+
+int fallthrough_attributed_labels(int n) {
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Adinesh-Reddy wrote:

I've added tests for [[clang::fallthrough]] and for an ordinary label followed by an attributed case label. I also split the test cases into separate functions

https://github.com/llvm/llvm-project/pull/234848