Re: logical replication launcher crash on buildfarm

On 2017-03-31 21:30:17 -0400, Robert Haas wrote:
> On Fri, Mar 31, 2017 at 9:26 PM, Petr Jelinek
> <petr(dot)jelinek(at)2ndquadrant(dot)com> wrote:
> >> Hmm, I don't know if there's any good reason not to just use strcmp(),
> >> but sure, OK. Committed and back-patched.
> >
> > Hmm culicidae still fails, this time only in parallel worker code. This
> > didn't happen on my machine which is strange. Looking at the code, we
> > are passing the fps->entrypoint as function pointer again so of course
> > it fails. We have some code to load libraries again but even that gets
> > initial entrypoint passed as function pointer
> > (ParallelExtensionTrampoline). I wonder if we'll have to generalize the
> > InternalBGWorkers even more to some kind of internal function name to
> > pointer map and add the parallel entry points there as well.
>
> Argh, I forgot about that. I think we need to use something like
> ParallelExtensionTrampoline all the time, not just for libraries.
> Since effectively, we've determined that postgres itself has the same
> problem.

I wonder if we shouldn't just introduce a KnownFunctionPointer[] map,
that can be used by various facilities (bgworkers themselves,
parallelism, and probably more coming). Otherwise we'll introduce
mechanisms like 7d8f6986b8 in multiple places.

- Andres