[Mesa-maintainers] make rules for generated files

[Jonathan Gray]

On Fri, Dec 16, 2016 at 11:30:17PM -0800, Matt Turner wrote:
> On Fri, Dec 16, 2016 at 9:38 PM, Jonathan Gray <jsg at jsg.id.au> wrote:
> > I'm not sure if others encounter this, but a problem I run into with
> > using the Mesa release tarballs is that if timestamps on files change
> 
> First obvious question: why do the timestamps change?

The process of importing Mesa into a larger cvs tree and checking it
out again changes the timestamps.

So I end up testing Mesa updates across a wide array of machines only to
have to scramble to fix issues that come up after import.

Mesa is part of a larger tree in OpenBSD (xenocara) which has xorg,
libdrm, xterm etc as well.  The build can't depend on anything not in
the xenocara or src (libc, kernel, posix utils etc) trees.

> 
> > rules to regenerate files get called even if python/xxd/bison etc
> > are not found.  In this case the Makefiles overwrite the generated
> > files in the distfile with empty files causing the build to error out.