Re: Project out of sources compilation

[Eli Zaretskii <eliz@gnu.org>]

> Date: Sun, 17 Mar 2024 18:33:21 +0100
> From: Ergus <spacibba@aol.com>
> Cc: dmitry@gutov.dev, emacs-devel@gnu.org
> 
> >Maybe I'm missing something, but isn't the build tree just one more
> >tree that is part of the project?  If so, can't you use
> >project-external-roots to add this tree to the project?  I thought
> >this was the mechanism to add trees to a project as included in the
> >original design of project.el and its support in Emacs?
> >
> 
> >> There is also some need for a 'bin' dir, that is, where the final executable will reside, useful to execute and debug with tools like gud and independent from 'build'...  For example in a python project this may be the project root OR where the file with __main__ resides, but a python project usually won't specify a build dir. But let's go for one thing at a time.
> >
> >Likewise here.
> >
> >Or what am I missing?
> 
> Hi Eli:
> 
> More or less we have it, that's why I said that there was just some
> (small) missing pieces.
> 
> We have the `project-external-roots`, but project.el uses them only to
> find files and regexps. So it looks like they are intended to be source
> places somehow.
> 
> The compile or debug programs doesn't know that they are intended to
> execute there.
> 
> However, a `build` or `bin` are different because they are where the
> `compile` or `gud` are intended to run; generally not a place to search
> for sources (unless the source is generated like config.h).

Are you saying that "M-x compile" and "M-x gdb" are not (yet)
supported by project.el?