[Bug middle-end/93806] Wrong optimization: instability of floating-point results with -funsafe-math-optimizations leads to nonsense

[bugdal at aerifal dot cx]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93806

--- Comment #32 from Rich Felker <bugdal at aerifal dot cx> ---
> A slightly modified version of the example, showing the issue with GCC 5 to 7 (as the noipa attribute directive has been added in GCC 8):

Note that __attribute__((__weak__)) necessarily applies noipa and works in
basically all GCC versions, so you can use it where you want this kind of
example for older GCC.