[FFmpeg-devel] [PATCH] build: fix make checkheaders in out-of-tree builds

[Ronald S. Bultje]

Hi,

On Sun, Jan 24, 2016 at 11:14 AM, Henrik Gramner <henrik at gramner.com> wrote:

> On Sun, Jan 24, 2016 at 5:02 PM, Hendrik Leppkes <h.leppkes at gmail.com>
> wrote:
> > Windows doesn't particularly care which slash direction you give it,
> > so no, that changes nothing. I'm not quite sure why it fails with the
> > include path this way, maybe some msys shenanigans.
> > For fun and giggles, I hard-coded the correct include path in the
> > common.mak file and that made config.h show up again of course, but
> > the good old compiler error came back just like before.
> >
> > Might be msys thats interfering here and translating something it
> > shouldn't, or double-translating something, I can't really tell just
> > from the commands it calls.
> > Like I said before, when initial MSVC support was build by Ronald and
> > Martin, there were lots of troubles with absolute paths, which in the
> > end were solved by not using them (sorry, no answers here).
>
> Is there any reason why we're using absolute paths then? Can't we just
> stick to relative paths with forward slashes since they seem to work
> with all tools?
>
> I added some code to x264's configure some time ago to convert
> absolute paths into relative paths just in order to avoid some
> MSYS/Cygwin headaches.


I think Andreas' original patch removed that so in-tree and out-tree builds
are bit-exact (i.e. the pathnames to in-tree source files are identical
between the two build types).

I don't know if that's worth it. Andreas seems to claim it is, others seem
to doubt it...

Ronald