Re: pg_config wrongly marked as not parallel safe?

On 2018-11-26 19:14:24 -0500, Joe Conway wrote:
> On 11/26/18 7:08 PM, Andres Freund wrote:
> > On 2018-11-26 19:04:46 -0500, Joe Conway wrote:
> >> Not intentional. Though, sitting here chatting with Stephen about it, I
> >> am now wondering if pg_config() should actually be marked immutable:
> >>
> >> select * from pg_config() where name = 'VERSION';
> >>   name   |     setting
> >> ---------+-----------------
> >>  VERSION | PostgreSQL 10.5
> >> (1 row)
> >>
> >> [...upgrade the postgres binaries...]
> >>
> >> select * from pg_config() where name = 'VERSION';
> >>   name   |     setting
> >> ---------+-----------------
> >>  VERSION | PostgreSQL 10.6
> >> (1 row)
> >>
> >> So the correct answer is probably to mark pg_config() stable, but it
> >> still seems to be parallel safe to me.
> > 
> > I don't think we should consider immutability to mean anything across
> > major versions. What'd be helped by doing that? We'd have to rule out
> > any behaviour change to any immutable function for that to make
> > sense. Including making an immutable function not immutable anymore.
> 
> Umm, this is a minor version not major.

Oops.

Greetings,

Andres Freund