Horton

Re: planner fails on HEAD

Merlin Moncure <mmoncure@gmail.com>

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From: Merlin Moncure <mmoncure@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Pavel Stehule <pavel.stehule@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2011-12-05T14:01:52Z
Lists: pgsql-hackers 
On Sun, Dec 4, 2011 at 4:55 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Pavel Stehule <pavel.stehule@gmail.com> writes:
>> it looks like gcc bug - gcc 4.5.1 20100924 (Red Hat 4.5.1) It was
>> configured just with --enable-debug and --enable-cassert
>
> Is this x86?  I can't reproduce it on x86_64.

reading all the comments in the gcc bug report, this is because x86
targets the x87 fpu by default which is where the bug is -- it's a
hardware problem.  x86_64 targets sse which has stricter standards for
rounding.  most x86 processors support sse -- is there a reason why we
don't target sse?

merlin