Hi, On 2023-04-14 15:21:18 -0400, Tom Lane wrote: > Andres Freund <and...@anarazel.de> writes: > > On 2023-04-14 13:21:33 -0400, Tom Lane wrote: > >> ... I'm not sure why only those two animals > >> are unhappy, but I think they have a point: typical ABIs don't > >> guarantee alignment of function stack frames to better than > >> 16 bytes or so. In principle the compiler could support a 4K > >> alignment request anyway by doing the equivalent of alloca(3), > >> but I do not think we can count on that to happen. > > > Hm. New-ish compilers seem to be ok with it. > > Oh! I was misled by the buildfarm label on morepork, which claims > it's running clang 10.0.1. But actually, per its configure report, > it's running > > configure: using compiler=gcc (GCC) 4.2.1 20070719
Huh. I wonder if that was an accident in the BF setup. > > Perhaps we should have a > > configure check whether the compiler is OK with that, and disable direct IO > > support if not? > > +1 for that, though. (Also, the fact that these animals aren't > actually failing suggests that 004_io_direct.pl needs expansion.) It's skipped, due to lack of O_DIRECT: [20:50:22] t/004_io_direct.pl .............. skipped: no O_DIRECT So perhaps we don't even need a configure test, just a bit of ifdef'ery? It's a bit annoying structurally, because the PG*Aligned structs are defined in c.h, but the different ways of spelling O_DIRECT are dealt with in fd.h. I wonder if we should try to move those structs to fd.h as well... Greetings, Andres Freund
