Fix ctan, ctanh overflow (bug 11521)

[Ryan S. Arnold]

On Tue, Apr 24, 2012 at 2:14 AM, Andreas Jaeger <aj@suse.com> wrote:
> On Monday, April 23, 2012 22:03:05 Adhemerval Zanella wrote:
>> On 04/09/2012 12:46 PM, Joseph S. Myers wrote:
>> > Bug 11521 reports a problem with ctanh returning incorrect results in
>> > cases where both numerator and denominator in the internal
>> > calculations overflowed.
>>
>> IBM long double version correction based on original patch and ulp file
>> update.
>>
>> ---
>>
>> 2012-04-17  Adhemerval Zanella  <azanella@linux.vnet.ibm.com>
>>
>>       [BZ #11521]
>>       * sysdeps/ieee754/ldbl-128ibm/s_ctanhl.c: Avoid internal overflow or
>>       cancellation in calculating denominator.
>>       * sysdeps/ieee754/ldbl-128ibm/s_ctanl.c: Likewise.
>>       * sysdeps/powerpc/fpu/libm-test-ulps: Update for ctan, ctanh fix.
>
> This looks fine to me but I'd like to have Ryan comment as well,

I'm going to apply it and check the results before giving my Ack.

Ryan