[Bug libfortran/125623] [17 Regression] write_float.def:44:37: error: implicit declaration o f function 'frexpl' [-Wimplicit-function-declaration]

[kargl at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=125623

--- Comment #7 from Steve Kargl <kargl at gcc dot gnu.org> ---
Comment on attachment 64638
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=64638
Patch

Won't this break bootstrapping gcc with the configure options

  --disable-libquadmath   do not build libquadmath directory
  --disable-libquadmath-support
                          disable libquadmath support for Fortran

For copysignl, you could use the rather poor

 long double
 copysignl (long double x, long double y)
 {
   long double ax;
   ax = (x < 0) ? -x : x;
   return (y < 0 ? -ax : ax);
 }

The only issue here is that +-0 cannot be used.