[clang] [Clang][Sema] Add -Wredundant-defer to diagnose redundant `_Defer`s (PR #225748)

[via cfe-commits]

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@@ -0,0 +1,151 @@
+// RUN: %clang_cc1 -std=c23 -fdefer-ts -fsyntax-only -verify %s -Wredundant-defer
+
+#define defer _Defer
+
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Expertcoderz wrote:

Support for `AttributedStmt` and `LabelStmt` has been implemented in d0a7f75e71afd8462ef7a25535650a469ade53cf.

https://github.com/llvm/llvm-project/pull/225748