[clang] [clang][C23] Allow NaN in constant evaluation (PR #167892)

[Hubert Tong via cfe-commits]

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@@ -222,6 +222,8 @@ C23 Feature Support
   the same translation unit but from different types.
 - ``-MG`` now silences the "file not found" errors with ``#embed`` when
   scanning for dependencies and encountering an unknown file. #GH165632
+- Allow NaN in constant expression evaluation to maintain consistency with
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hubert-reinterpretcast wrote:

Is there a belief that the committee will not extend the design principles it took for the library calls to the core language and essentially match the GCC behaviour column in https://web.archive.org/web/20251117163349/https://isocpp.org/files/papers/D3899R0.html#implementation-divergence?

I am not aware of any alternative proposals being championed.

https://github.com/llvm/llvm-project/pull/167892