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Re: 1.5.24: sin() bug
Dave Korn wrote:
> Since when was pi less than 2^-27?
This is a kernel sin, a function over the limited range [-pi/4, pi/4],
where the general case sin is reduced to kernel sin by the remainder of
> I think it may be an artefact of FP precision and/or rounding mode, but I'd
> need to do more experiments to make sure. OTOH it could be an artifact of the
> printf %g specfier. Like I said, more experimentation is needed!
A problem with the testcase is the .10. It helps to expand that so that
you see the entire value. Or use %a. newlib returns 3CED1A62633145C0
whereas both MSVCRT and x86 linux seem to return 3CED1A6000000000. It
sort of looks like a truncation problem but since glibc agrees with
msvcrt (shock!) I tend to think the latter is right. The actual
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