Re: longfin and tamandua aren't too happy but I'm not sure why

On Wed, Sep 28, 2022 at 11:57 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
> Dilip Kumar <dilipbalaut(at)gmail(dot)com> writes:
> > Btw, I think the reason for the bus error on wrasse is the same as
> > what is creating failure on longfin[1], I mean this unaligned access
> > is causing Bus error during startup, IMHO.
>
> Maybe, but there's not a lot of evidence for that. wrasse got
> through the test_decoding check where longfin, tamandua, kestrel,
> and now skink are failing. It's evidently not the same issue
> that the 32-bit animals are choking on, either. Looks like yet
> a third bug to me.

I think the reason is that "longfin" is configured with the
-fsanitize=alignment option so it will report the failure for any
unaligned access. Whereas "wrasse" actually generates the "Bus error"
due to architecture. So the difference is that with
-fsanitize=alignment, it will always complain for any unaligned access
but all unaligned access will not end up in the "Bus error", and I
think that could be the reason "wrasse" is not failing in the test
decoding.

Yeah but anyway this is just a theory behind why failing at different
places but we still do not have evidence/call stack to prove that.

--
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com