[clang] [C23] Implement WG14 N3037 (PR #132939)

[Aaron Ballman via cfe-commits]

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@@ -478,16 +478,24 @@ def warn_odr_function_type_inconsistent : Warning<
   "external function %0 declared with incompatible types in different "
   "translation units (%1 vs. %2)">,
   InGroup<ODR>;
+def err_odr_attr_inconsistent : Error<
+  "attribute %0 is incompatible%select{| in different translation units}1">;
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AaronBallman wrote:

Good catch, this is dead code and can be removed

https://github.com/llvm/llvm-project/pull/132939