Re: Should we work around msvc failing to compile tab-complete.c?

On Tue, 9 Jul 2024 at 17:23, Andres Freund <andres(at)anarazel(dot)de> wrote:

> Hi,
>
> On 2024-07-09 09:14:33 +0100, Dave Page wrote:
> > On Mon, 8 Jul 2024 at 21:08, Andres Freund <andres(at)anarazel(dot)de> wrote:
> > > I think we'd need to backpatch more for older branches. At least
> > >
> > > commit 3f28bd7337d
> > > Author: Thomas Munro <tmunro(at)postgresql(dot)org>
> > > Date: 2022-12-22 17:14:23 +1300
> > >
> > > Add work-around for VA_ARGS_NARGS() on MSVC.
> > >
> > >
> > > Given that - afaict - tab completion never used to work with msvc, I
> think
> > > it'd be ok to just do it in 17 or 16+17 or such. Obviously nobody is
> > > currently
> > > building with readline support for windows - not sure if any packager
> is
> > > going
> > > to go back and add support for it in older branches.
> >
> >
> > Packagers aren't likely to be using readline, as it's GPL and it would
> have
> > to be shipped with packages on Windows.
>
> I'm not sure (I mean that literally, not as a way to state that I think
> it's
> not as you say) it'd actually be *that* big a problem to use readline -
> sure
> it'd make psql GPL, but that's the only thing using readline. Since psql
> doesn't link to extensible / user provided code, it might actually be ok.
>
> With openssl < 3.0 the mix between openssl and readline would be
> problematic,
> IIRC the licenses aren't really compatible. But luckily openssl relicensed
> to
> apache v2.
>

Certainly in the case of the packages produced at EDB, we didn't want any
potential surprises for users/redistributors/embedders, so *any* GPL was a
problem.

> But that is pretty orthogonal to the issue at hand:
>

Right.

What is more relevant is that as far as I can see, we've never actually
supported either libedit or readline in MSVC++ builds - which kinda makes
sense because Windows terminals are very different from traditional *nix
ones. Windows isn't supported by either libedit or readline as far as I can
see, except through a couple of forks.

I imagine from mingw/cygwin builds, readline would only actually work
properly in their respective terminals.

--
Dave Page
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