https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82318
--- Comment #8 from Vincent Lefèvre <vincent-gcc at vinc17 dot net> --- (In reply to Rich Felker from comment #7) > Note that such an option would be nice to have anyway, for arbitrary > functions, since it's necessary for being able to call code that was > compiled with -fexcess-precision=fast from code that can't accept the > non-conforming/optimizer-unsafe behavior and safely use the return value. It > should probably be an attribute, with a flag to set the global default. For > example, __attribute__((__returns_excess_precision__)). If you're talking about arbitrary functions, they may have been implemented in languages other than C, anyway. So that's an ABI issue. If the ABI allows excess precision, then GCC must assume that excess precision is possible.
