[Bug libstdc++/118841] please do not use long double in generate_canonical when the range is small enough

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118841

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
It's not about the range, it's the precision within the range. But I think it
can be changed.