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

[Aaron Ballman via cfe-commits]

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@@ -1129,7 +1137,9 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
   DefineTypeSize("__LONG_MAX__", TargetInfo::SignedLong, TI, Builder);
   DefineTypeSize("__LONG_LONG_MAX__", TargetInfo::SignedLongLong, TI, Builder);
   DefineTypeSizeAndWidth("__WCHAR", TI.getWCharType(), TI, Builder);
+  DefineTypeMin("__WCHAR", TI.getWCharType(), TI, Builder);
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AaronBallman wrote:

We should also update https://github.com/llvm/llvm-project/blob/adfb3be9d098e4c12895957f9ac3fc9d892b45a9/clang/lib/Headers/stdint.h#L821

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