[marcosdumay]

> Some applications are too slow without them.

I fully expect the intersection between programs where floating point instructions are a speed bottleneck and programs where the numerical instability that fast_math can cause is not a problem is the empty set.

[grogers]

IIRC we used -ffast-math for numerical simulations of radar cross sections. Fast math was a decent perf win but didn't have any negative effects on the results.

Most programs don't care about the difference between ((a+b)+c) vs (a+(b+c)). Why bother with NaNs if you know you can't get them? Etc.

[subharmonicon]

Something akin to fast-math is the default for some shading languages (although some have switched to fast-math-but-preserve-NaN-and-INF).