Re: pg11.1 jit segv

Hi,

On 2018-11-15 16:39:59 -0600, Justin Pryzby wrote:
> Crash is reproducible but only when JIT=on.
>
> postgresql11-llvmjit-11.1-1PGDG.rhel7.x86_64
>
> [2769871.453033] postmaster[8582]: segfault at 7f083bddb780 ip 00007f08127e814e sp 00007ffe463506e0 error 4
> [2770774.470600] postmaster[29410]: segfault at 7f0812eeb6c8 ip 00007f08127eb4f0 sp 00007ffe463506e0 error 4
>
> Core was generated by `postgres: telsasoft ts 192.168.122.11(41908) SELECT '.
> Program terminated with signal 11, Segmentation fault.

Thanks for reporting!

> (gdb) bt
> #0 0x00007f08127e814e in ?? ()
> #1 0x0000000000000000 in ?? ()

Could you enable jit_debugging_support and reproduce? That should give
a more useful backtrace.

It'd also be interesting if toggling jit_inline_above_cost=-1,
jit_optimize_above_cost=-1 and jit_tuple_deforming=false, each set
individually, make a difference.

> Let me know if there's anything else I can provide.

Any way for me to reproduce this locally? I.e. can you narrow this down
to a reproducible test case?

Greetings,

Andres Freund