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Re: Rounding errors using doubles?
- To: ross dot s at ihug dot co dot nz
- Subject: Re: Rounding errors using doubles?
- From: craig at jcb-sc dot com
- Date: 19 Mar 1999 14:20:42 -0000
- Cc: egcs at egcs dot cygnus dot com
- Cc: craig at jcb-sc dot com
- References: <002d01be71aa$30d420e0$a8a11dcb@animal.ihug.co.nz>
>Both compilers have options to force pure 64-bit arithmetic (53-bit
>precision) throughout (at some cost in speed): -ffloat-store on EGCS,
>/Op on MSVC.
Take -ffloat-store off that list: it doesn't do the above. It affects
only explicit *stores* to *variables*, not intermediate coputations. egcs
provides no way to force 64-bit FP arithmetic. In fact, I'd be surprised
if -ffloat-store "improved" the behavior of the (buggy) program originally
submitted in this thread.
Other than that, thanks for the decent explanation -- if this isn't
in the FAQ, it should be, and if it is, we should refrain from
repeating it, and point people there instead!
tq vm, (burley)