[clang] [C2y] Implement WG14 N3411 (PR #130180)

[via cfe-commits]

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@@ -0,0 +1,14 @@
+// RUN: %clang_cc1 -verify=c2y -std=c2y -Wall -pedantic %s
+// RUN: %clang_cc1 -verify -Wnewline-eof -std=c2y -Wall -pedantic %s
+// RUN: %clang_cc1 -verify -std=c23 -Wall -pedantic %s
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cor3ntin wrote:

maybe add a test for c23, no warning / no pedantic

https://github.com/llvm/llvm-project/pull/130180