From: | Andres Freund <andres(at)anarazel(dot)de> |
---|---|
To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com>, Andrew Gierth <andrew(at)tao11(dot)riddles(dot)org(dot)uk>, Victor Wagner <vitus(at)wagner(dot)pp(dot)ru>, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org> |
Subject: | Re: Bug fix for glibc broke freebsd build in REL_11_STABLE |
Date: | 2018-09-05 16:42:06 |
Message-ID: | 20180905164206.x3ghtsfsnzthwz7o@alap3.anarazel.de |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Hi,
On 2018-09-05 10:05:26 -0400, Tom Lane wrote:
> Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com> writes:
> > On 05/09/2018 02:51, Andres Freund wrote:
> >> My current proposal is thus to do add a check that does
> >> #if defined(__clang__) && defined(__i386__) && !defined(__SSE2_MATH__)
> >> something-that-fails
> >> #endif
> >> in an autoconf test, and have configure complain if that fails.
>
> > Would this not be invalidated if the bug you have filed gets fixed?
Realistically we're going to be running into old versions of clang for a
long time. And the importance of running i386 without SSE2 surely isn't
increasing. So I don't really see an urgent need to do anything about
it. And if it gets fixed, and we care, we can just add a clang version
check to the test.
> Perhaps, but how would autoconf tell that? I wouldn't have any confidence
> in a runtime test, as it might or might not trigger the bug depending on
> all sorts of factors like -O level.
>
> In any case, it seems like "use -msse2 on x86" is good advice from a
> performance standpoint even if it doesn't prevent a compiler bug.
Indeed.
> One thought is that maybe we should provide a way to override this,
> in case somebody really can't or doesn't want to use -msse2, and
> is willing to put up with platform-dependent float behavior.
IDK, people that are capable of making that decision can just hack
configure.
Greetings,
Andres Freund
From | Date | Subject | |
---|---|---|---|
Next Message | Peter Eisentraut | 2018-09-05 16:46:51 | Re: [HACKERS] Proposal to add work_mem option to postgres_fdw module |
Previous Message | Chris Travers | 2018-09-05 16:40:36 | Re: Funny hang on PostgreSQL 10 during parallel index scan on slave |