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Re: Changing the default i387 precision

Joerg Sonnenberger <joerg%britannica.bec.de@localhost> writes:

> On Sat, May 04, 2013 at 07:14:00AM -0400, Greg Troxel wrote:
>> So are you proposing then
>>   1) Make gcc and clang use larger storage (maybe already true) and avoid
>>   SSE instructions for variables declared as long double?
> That's already the case. long double computations always use the i387.
> The point is that I want them to get the extended precision.

If what you want to do now is to change the way rounding is handled so

   long double variables get the 80-bit precision


   making (non-long) doubles get results that don't comply with IEEE754
   (by using extended precision intermedate values)

then that sounds fine.  But I can't really tell what you want to change.

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