[Bug fortran/52413] Incorrect behavior of FRACTION when applied to a constant

[fxcoudert at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52413

--- Comment #9 from Francois-Xavier Coudert <fxcoudert at gcc dot gnu.org> ---
> Before going to the machinery in comment #6, the following patch (i.e.,
> without any mpfr_copysign)

Yep, you're right, no need for mpfr_copysign. Your patch looks good, if we
don't want to introduce mpfr_frexp.