On 02/03/2014 06:37 PM, Andres Freund wrote:
> On 2014-02-03 12:00:40 +0800, Craig Ringer wrote:
>> I think it's a good thing personally - we shouldn't be exporting every
>> little internal var in the symbol table.
>>
>> If we built with -fvisibility=hidden on 'nix there'd be no need to
>> complain about commits being on on 'nix then breaking on Windows, 'cos
>> the 'nix build would break in the same place. That's all or nothing
>> though, there's no "vars hidden, procs exported" option in gcc.
>
> I think that'd be an exercise in futility. We're not talking about a
> general purpose library here, where I agree -fvisibility=hidden is a
> useful thing, but about the backend. We'd break countless extensions
> people have written. Most of those have been authored on *nix.
> To make any form of sense we'd need to have a really separate API
> layer between internal/external stuff. That doesn't seem likely to
> arrive anytime soon, if ever.
> I think all that would achieve is that we'd regularly need to backpatch
> visibility fixes. And have countless pointless flames about which
> variables to expose.
Fair point. If we're not going to define a proper API, then export
control is not useful. And since there isn't a proper API, nor any on
the cards, _that_ is a reasonable reason to just export all.
-- Craig Ringer http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services
