Allow large f64-to-f32 to saturate to infinity #186
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The implementation of `<f64 as ToPrimitive>::to_f32` was written at a time when float-to-float overflow was though to be undefined behavior, per rust-lang/rust#15536, but this was later determined to be fine. Casting a large `f64` to `f32` just results in an infinity with the matching sign. The sign gives more information than if `to_f32` just returns `None`, so now we let these infinities through as a result. See also rust-num/num-bigint#163 and rust-num/num-rational#83.
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The implementation of
<f64 as ToPrimitive>::to_f32was written at atime when float-to-float overflow was though to be undefined behavior,
per rust-lang/rust#15536, but this was later determined to be fine.
Casting a large
f64tof32just results in an infinity with thematching sign. The sign gives more information than if
to_f32justreturns
None, so now we let these infinities through as a result.See also rust-num/num-bigint#163 and rust-num/num-rational#83.