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Re: Changing the default i387 precision

On Sat, May 04, 2013 at 07:11:07PM +0200, Joerg Sonnenberger wrote:
> The default rounding mode to give full internal precision.

Precision, not rounding, right?

I.e. you are not talking about fpsetround() but the precision flags
that are also part of the i386 controll word (en_cw in struct env87)
and you want to change the __NetBSD_NPXCW__ value, which is assigned
to that in setregs(), so each new process starts with this setting.

My i387 fu is too weak to understand the full implications this has
for operations on the various length float/double/long double values
at the C level, could you please elaborate those a bit?



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