On 2017-08-16 09:57:35 -0700, Peter Geoghegan wrote: > On Wed, Aug 16, 2017 at 9:55 AM, Andres Freund <and...@anarazel.de> wrote: > > On 2017-08-16 11:16:58 -0400, Tom Lane wrote: > >> Heikki Linnakangas <hlinn...@iki.fi> writes: > >> > A couple of 32-bit x86 buildfarm members don't seem to be happy with > >> > this. I'll investigate, but if anyone has a clue, I'm all ears... > >> > >> dromedary's issue seems to be alignment: > >> > >> TRAP: UnalignedPointer("(((uintptr_t) ((uintptr_t)(ptr)) + ((8) - 1)) & > >> ~((uintptr_t) ((8) - 1))) != (uintptr_t)(ptr)", File: > >> "../../../../src/include/port/atomics.h", Line: 452) > >> 2017-08-16 11:11:38.558 EDT [75693:3] LOG: server process (PID 76277) was > >> terminated by signal 6: Abort trap > >> 2017-08-16 11:11:38.558 EDT [75693:4] DETAIL: Failed process was running: > >> select count(*) from a_star; > >> > >> Not sure if this is your bug or if it's exposing a pre-existing > >> deficiency in the atomics code, viz, failure to ensure that > >> pg_atomic_uint64 is actually a 64-bit-aligned type. Andres? > > > > I suspect it's the former. Suspect that the shared memory that holds > > the "parallel desc" isn't properly aligned: > > Clang has an -fsanitize=alignment option that may be useful here.
Given that we're crashing in an assert that does nothing but check for alignment, before the memory is actually used in a "dangerous" manner, I don't quite see how? Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers