On 2017-10-02 15:01:36 -0700, Andres Freund wrote: > On 2017-10-02 17:57:51 -0400, Tom Lane wrote: > > Andres Freund <and...@anarazel.de> writes: > > > Done that way. It's a bit annoying, because we've to take care to > > > initialize the "unused" part of the array with a valid signalling it's > > > an unused mapping. Can't use 0 for that because fmgr_builtins is a > > > valid entry. > > > > The prototype code I posted further upthread just used -1 as the "unused" > > marker. There's no reason the array can't be int16 rather than uint16, > > and "if (index < 0)" is probably a faster test anyway. > > Right, but whether we use -1 or UINT16_MAX or such doesn't matter. The > relevant bit is that we can't use 0, so we can't rely on the rest of the > array being zero initialized, but instead of to initialize all of it > explicitly. I've no real feelings about using -1 or UINT16_MAX - I'd be > very surprised if there's any sort of meaningful performance difference.
I pushed a further cleaned up version of these two patches. If you see a way to avoid initializing the "trailing" part of the fmgr_builtin_oid_index in a different manner, I'm all ears ;) Greetings, Andres Freund -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers