This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: Fix exp missing underflows (bug 15268, bug 15425)
- From: Adhemerval Zanella <azanella at linux dot vnet dot ibm dot com>
- To: libc-alpha at sourceware dot org
- Date: Wed, 04 Dec 2013 10:18:05 -0200
- Subject: Re: Fix exp missing underflows (bug 15268, bug 15425)
- Authentication-results: sourceware.org; auth=none
- References: <Pine dot LNX dot 4 dot 64 dot 1312031836230 dot 7734 at digraph dot polyomino dot org dot uk> <529E4764 dot 7020100 at suse dot com>
On 03-12-2013 19:04, Andreas Jaeger wrote:
> On 12/03/2013 07:37 PM, Joseph S. Myers wrote:
>> Bugs 15268 and 15425 are cases of missing underflow exceptions from
>> dbl-64 exp, where the result produced by either scaling down or the
>> mpa.c multiple-precision code does not involve any inexact underflows
>> (it may or may not involve an exact underflow which doesn't set the
>> underflow flag) even though the actual exp operation is inexact (for
>> all finite nonzero arguments) and so the exception should be raised on
>> underflow. This patch fixes them by checking for a result small
>> enough to require an underflow exception, in the cases where this
>> issue might arise, and ensuring an exception is raised in that case.
>>
>> Tested x86_64 and x86 and ulps updated accordingly.
> ok, thanks,
>
> Andreas
Thanks for fixing it Joseph.