Re: pgsql: Implement streaming mode in ReorderBuffer.

Amit Kapila <akapila(at)postgresql(dot)org> writes:
> Implement streaming mode in ReorderBuffer.

I notice that new buildfarm member wrasse is unhappy about some of the
code added by this commit:

"/export/home/nm/farm/studio64v12_6/HEAD/pgsql.build/../pgsql/src/backend/replication/logical/reorderbuffer.c", line 2510: Warning: Likely null pointer dereference (*(curtxn+272)): ReorderBufferProcessTXN

It's griping about this:

curtxn->concurrent_abort = true;

and I think it's got a point. There is little if any reason to have
confidence that curtxn must be non-NULL when this code is reached,
because it's in a PG_CATCH segment and there is a lot of code within
the PG_TRY that could throw an error before the spot where curtxn
is set. Not to mention that curtxn is set only conditionally.

So I think

if (curtxn)
curtxn->concurrent_abort = true;

would be cheap insurance against a core dump. Or maybe we should
do something else, but this seems really rickety as-is.

(wrasse seems to be generating boatloads of utterly useless warnings
otherwise, but after sifting through the chaff I did find this one.)

regards, tom lane