On Wed, Oct 31, 2018 at 9:12 AM Thomas Koenig <tkoe...@netcologne.de> wrote:
> > Makefile.am:48: warning: source file 'caf/single.c' is in a subdirectory, > > Makefile.am:48: but option 'subdir-objects' is disabled > > automake: warning: possible forward-incompatibility. > > automake: At least a source file is in a subdirectory, but the > 'subdir-objects' > > automake: automake option hasn't been enabled. For now, the > corresponding output > > automake: object file(s) will be placed in the top-level directory. > However, > > automake: this behaviour will change in future Automake versions: they > > will > > automake: unconditionally cause object files to be placed in the same > subdirectory > > automake: of the corresponding sources. > > automake: You are advised to start using 'subdir-objects' option > throughout your > > automake: project, to avoid future incompatibilities. > > > > I think it's best for the relevant maintainers to add subdir-objects > > and do any other associated Makefile.am changes needed. In some cases > > the paths in the warnings involved ../; I don't know if that adds any > > extra complications to the use of subdir-objects. > > I'm not an automake expert, but I hope to be able to figure out > what is needed. If not, I guess I'll just ask :-) > My understanding is that we need to add 'subdir-objects' to AM_INIT_AUTOMAKE in configure.ac. See e.g. https://autotools.io/automake/options.html (that site is pretty good for describing 'best practices' for modern autotools; there's unfortunately a lot of very outdated autotools tutorials around) What is the plan for the previous branches? Currently, it is necessary > to keep around a special version of automake etc for > --enable-maintainer-mode to work. Backporting a patch which > involves regeneration of files in libgfortran/generated from > the files in libgfortan/m4 would then require keeping two versions > of the relevant tools around, and switching between them. > > Would it make sense to backport because of this? > +1 -- Janne Blomqvist