[clang] [Clang] Define `__WCHAR_MIN__` and related macros (PR #208135)

[Zeyi Xu via cfe-commits]

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@@ -1182,6 +1192,7 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
   DefineType("__WCHAR_TYPE__", TI.getWCharType(), Builder);
   DefineType("__WINT_TYPE__", TI.getWIntType(), Builder);
   DefineTypeSizeAndWidth("__SIG_ATOMIC", TI.getSigAtomicType(), TI, Builder);
+  DefineTypeMin("__SIG_ATOMIC", TI.getSigAtomicType(), TI, Builder);
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zeyi2 wrote:

I also updated `SIG_ATOMIC_MAX`, thanks for reviewing!

https://github.com/llvm/llvm-project/pull/208135