pi/2 again...

[David Miller]

From: "Joseph S. Myers" <joseph@codesourcery.com>
Date: Thu, 2 May 2013 20:21:37 +0000

> pi/2 rounded to nearest for ldbl-128 is 
> 0x1.921fb54442d18469898cc51701b8p+0L (computed with MPFR).  The cosine of 
> that value, again rounded to nearest, is 
> 0x3.9a252049c1114cf98e804177d4c8p-116L.
> 
> That cosine is exactly the value currently expected in libm-test.inc (but 
> MPFR prefers a different exponent when displaying it).  If M_PI_2l, shown 
> as a hex float, is equal to the value given above, then you have a problem 
> with the ldbl-128 cos function being inaccurate near pi/2 (maybe a range 
> reduction issue) - which will need filing as such in Bugzilla and fixing.  

M_PI_2l is printed as a hex float equal to the value above so it's a cos()
issue, bugzilla filed.