<__msvc_math.hpp>: Restore and test _USE_MATH_DEFINES support - #6446
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Stephan T. Lavavej (StephanTLavavej) wants to merge 1 commit into
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<__msvc_math.hpp>: Restore and test _USE_MATH_DEFINES support#6446Stephan T. Lavavej (StephanTLavavej) wants to merge 1 commit into
<__msvc_math.hpp>: Restore and test _USE_MATH_DEFINES support#6446Stephan T. Lavavej (StephanTLavavej) wants to merge 1 commit into
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Followup to #6413.
While validating
/Zc:cmath(which enables LLVM libc generally, and C++23/26constexpr <cmath>specifically) against our Real World Code test suite of popular open-source projects, Cody Miller (@Codiferous) found that usage of our non-Standard math macros is extremely widespread, and this is a major blocking issue for/Zc:cmathadoption.As a general rule we still want to avoid providing non-Standard legacy math machinery in our new replacement header, but in this case we need to compromise for the sake of practicality. The good news is that this stuff is opt-in via an
_Uglymacro, so users won't get it if they don't specifically ask for it.