Re: [PATCH] In _IEEE_LIBM mode, use weak symbols instead of wrapper funcs [v2]

Keith Packard wrote:

>> So the question is, is there any reason why _IEEE_LIBM should not be the default?
>
> I don't think we can do that if we want to provide a POSIX-compatible
> library anywhere -- POSIX defines errno values for specific cases.

I didn't say completely remove POSIX errno support. The new math functions do have
POSIX errno support and are equally space and performance efficient  whether you want
errno or not (currently it uses WANT_ERRNO but it could check _IEEE_LIBM too).

There is no difference in the math functions either way - the only conditional compilation is
in libm/common/math_err.c. So you really can get the best of both worlds without any
wrappers and without adding even more complex hacks.

Note also that most of the math functions won't ever be used by embedded applications.
So we only need to consider the commonly used math functions - the new math functions
cover most of those already.

Wilco