Re: planner fails on HEAD
Pavel Stehule <pavel.stehule@gmail.com>
From: Pavel Stehule <pavel.stehule@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2011-12-04T22:52:41Z
Lists: pgsql-hackers
2011/12/4 Tom Lane <tgl@sss.pgh.pa.us>: > Pavel Stehule <pavel.stehule@gmail.com> writes: >> 2011/12/4 Tom Lane <tgl@sss.pgh.pa.us>: >>> [ scratches head ... ] Given that it got past the previous assertions, >>> surely that ought to be impossible. Could we see the values of >>> cost_mergejoin's local variables, please? > >> It is strange > >> when I put a fprintf(stderr, "const literal") to exactly before or >> somewhere after assertion, then assertion is ok. Without fprintf >> assertion fails again > >> 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 > > Hmm. I'm betting that gcc has flushed one value to memory but the other > one is still in a register that's wider than memory, creating a roundoff > hazard. Can you look at the generated assembly code? I can, but tomorrow evening, I'll send a code Regards Pavel > > regards, tom lane