From: | Martin Liška <marxin(dot)liska(at)gmail(dot)com> |
---|---|
To: | Andres Freund <andres(at)anarazel(dot)de> |
Cc: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>, pgsql-bugs(at)lists(dot)postgresql(dot)org |
Subject: | Re: BUG #15121: Multiple UBSAN errors |
Date: | 2018-03-19 20:01:28 |
Message-ID: | CAObPJ3N+ssZqxh=MmDUKHouT2b2qA-a7PqDeJTAJHUuLkPUtLQ@mail.gmail.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-bugs |
OK guys, you were right, it's miscompilation caused by GCC:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84969
Martin
On 19 March 2018 at 20:18, Andres Freund <andres(at)anarazel(dot)de> wrote:
> On 2018-03-19 14:41:23 -0400, Tom Lane wrote:
>> Andres Freund <andres(at)anarazel(dot)de> writes:
>> > On 2018-03-19 14:20:33 -0400, Tom Lane wrote:
>> >> I tried -O3 with gcc 7.3.1 (Fedora 26), and that passes check-world
>> >> just fine. Then I tried -O3 with gcc 8.0.1 (prerelease Fedora 28),
>> >> and indeed that's got some problems.
>>
>> >> Note that 1-D and 2-D arrays print fine, it's only 3-D or deeper
>> >> that print wrong. Very odd. Maybe it's bad code on our part,
>> >> but I think the odds are at least as good that it's a new gcc bug.
>>
>> > Might be worth trying with a new clang, I think it's been a bit ahead on
>> > the quality of the ubsan (et al) integration quality.
>>
>> I'm not talking about ubsan, I'm just talking about whether our regression
>> tests pass with the higher -O level.
>
> Oh. I think I'll setup two BF animals that continually run using
> debian's gcc-snapshot package, once with O0 and once with O3.
>
> Greetings,
>
> Andres Freund
From | Date | Subject | |
---|---|---|---|
Next Message | Tomas Vondra | 2018-03-19 21:24:53 | Re: BUG #15121: Multiple UBSAN errors |
Previous Message | Andres Freund | 2018-03-19 19:18:53 | Re: BUG #15121: Multiple UBSAN errors |