Re: [Libmesh-devel] Still Really Dislike Automake

[Derek G. <fri...@gm...>]

On Thu, Aug 30, 2018 at 4:02 PM Jed Brown <je...@je...> wrote:

> Derek Gaston <fri...@gm...> writes:
>
> > Or: like I said earlier, maybe we just maintain two systems.  PETSc has
> had
> > several different build systems all at the same time because developers
> > wanted different things.
>
> It's important to note that all build systems have used the same
> underlying specification.  The GNU make and CMake systems both use/used
> a generator script that read the file lists from legacy makefiles.
> We've ditched CMake and are phasing out the legacy makefiles because GNU
> make is so much faster, more reliable, and less code.
>

Thanks Jed - definitely appreciate your insight!


> I'm with Paul that out-of-source builds are essential, but it isn't hard
> to put build products in a directory of the user's choosing (a la
> PETSC_ARCH).  I have 35 PETSC_ARCHes at the moment and I appreciate
> being able to switch between them and update builds in a couple seconds.
>

I agree - I do think that a GNU Make solution can do out-of-source builds.
And if that's what's needed then we can make it happen here.


> The hard part is _not_ make (unless you absolutely need to work with the
> intersection of GNU and BSD makes).  Configuration is hard and all
> solutions are terrible.
>

Luckily we have a really good set of configure scripts.  "configure" has
its own problems... but we (mostly because of hard work by John) have a
pretty good handle on it.  We wouldn't need to re-engineer that for this
new effort.

Derek