Fix documentation of __STDC__ #5431
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getting `__STDC__=1` requires setting `/Za` or `/Zc:__STDC__`. It doesn't seem to matter whether/what `/std` is set to.
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Learn Build status updates of commit b51bd8f: ✅ Validation status: passed
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getting
__STDC__=1requires setting/Zaor/Zc:__STDC__. It doesn't seem to matter whether/what/stdis set to.As best I can tell (experimenting locally with Visual Studio 2022 17.14, and on compiler explorer back to 17.2), the changes made in c139817 do not seem to be accurate. setting
/std:c11or/std:c17do not result in having#define __STDC__ 1. See https://godbolt.org/z/65YvxPYM3This agrees with the documentation of https://learn.microsoft.com/en-us/cpp/build/reference/zc-stdc?view=msvc-170, which says
So I suspect having
/std:c11set__STDC__=1may have originally been the original intent (and maybe it was true in a preview version?) but it doesn't seem to behave that way in the 17.2 or 17.14 release...