[libcxx-commits] [PATCH] D137502: [libc++][math.h] move #undefs to the top and guard explicitly against MSVCRT instead

[Louis Dionne via Phabricator via libcxx-commits]

ldionne added a comment.

In addition, if a library does not define e.g. `isnan` at all (neither as a macro nor as a function), our `<math.h>` will currently do the wrong thing because we won't define `isnan` at all. After this patch, we'll define it using the builtins, which is what we want to be doing. This makes the library easier to port to freestanding platforms.


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  https://reviews.llvm.org/D137502/new/

https://reviews.llvm.org/D137502