Re: [PATCH 1/3] Vala: Fix build when using per-target VALAFLAGS

[Ralf Wildenhues]

Hi Jürg,

* Jürg Billeter wrote on Sun, May 17, 2009 at 10:01:38AM CEST:
> On Sun, 2009-05-17 at 09:41 +0200, Ralf Wildenhues wrote:
> 
> > Please note that I'm really close to finishing 1.11, and considering
> > to postpone this change unless there is an easy way out.
> 
> I expect per-target VALAFLAGS to be relatively common as VALAFLAGS will
> be used for all libraries. While using the same Vala source file in
> multiple targets might be useful in some occasions, I'd expect it to be
> less used than per-target VALAFLAGS. In my opinion, the Vala support in
> automake 1.11 would be a lot more useful with the patchset applied.

Yeah, you're probably right.

> Unfortunately, I don't have an idea right now how to easily guard
> against the issue in automake.in except maybe using something like a
> global array of processed .vala source files.

It is not useful to rush an ugly patch in right now, just to try to hack
around this.  Let's fix this right for 1.11.1, and have the ugly change
go in right now.

I'm going to push your three patches, but I should note that patch 3/3
breaks BSD make, due to this feature (from info Autoconf "Make Target
Lookup"):

     OpenBSD and FreeBSD `make', however, never perform a `VPATH' search
  for a dependency that has an explicit rule.  This is extremely annoying.

It means in practice, that anything referred to with $(srcdir)/ prefixed
as a target, needs to always be prefixed when used as prerequisite as
well.  You can test this with pmake or freebsd-make on Debian.

Oh well, temporarily adding GNU make to the prerequisites for building
Vala with Automake 1.11 should be tolerable.

Thanks,
Ralf