Since C99, `FLT_EVAL_METHOD` should be left for the compiler/libc to
define. Its redefinition breaks compilation with picolibc as the
target's libc, since it defines said symbol in math.h before the libm
define is evaluated by the compiler.
In its place, there is a check to make sure floating point type sizes
are what are expected to be, triggering a compilation error if those
assumptions are no longer valid.
Co-authored-by: Angus Gratton <angus@redyak.com.au>
Signed-off-by: Alessandro Gatti <a.gatti@frob.it>
acoshf, asinhf, atanhf were added from musl. mathsincos.c was
split up into its original, separate files (from newlibe-nano-2).
tan was added.
All of the important missing float functions are now implemented,
and pyboard now passes tests/float/math_fun.py (finally!).
Top-level lib directory is for standard C libraries that we want to
provide our own versions of (for efficiency and stand-alone reasons).
It currently has libm in it for math functions.
Also add atanf and atan2f, which addresses issue #837.
