Sorry for delay (surgery funsies) > So it's already producing inaccurate results for code that sets precision control? Might as well just switch over to hardwa

Sorry for delay (surgery funsies) > So it's already producing inaccurate results for code that sets precision control? Might as well just switch over to hardware fp32 and fp64 /s :D But in practice the only reason for changing the x87 precision is performance, which was then simply retained in hardware for backwards compatibility. Modern code (as in >= SSE era) simply uses fp32 or fp64 which is faster, more memory compact, has vector units, has a much more sane ISA, etc. Anyone who does try to toggle x87 mode in general is in for a world of hurt because the system libraries all assume the unit is operating in default state. You are correct that the only reason x86_64 needs x87 is that the unix x86_64 ABI decided to specify the already clearly deprecated format the implementation of long double. I often looked wistfully at win64 where long double == double.