Re: CHECK_STRUCTS/dmpstruct.h mechanism is broken.

[Andy Moreton <andrewjmoreton@gmail.com>]

On Wed 10 Apr 2019, Paul Eggert wrote:

> On 4/10/19 6:12 AM, Andy Moreton wrote:
>> this breaks out-of-tree builds, as make tries to use
>> /path/to/emacs/admin/charsets/Makefile rather than the correct path
>> <builddir>/admin/charsets/Makefile:
>
> Sorry, my tests didn't include a complete out-of-tree bootstrap. I
> installed the attached patch to fix that problem, along with the
> problem's other instance. The other -C changes should be OK. You're
> correct that some of the -C changes were unrelated to the original
> patch. Still, they make the Makefile more consistent and I'd like to
> keep the ones that work.

The minimal fixes you have committed work for me for a bootstrap build
from a completely clean tree (after 'git clean -Xdf').

I'm not convinced that computing filenames using GNU make functions
rather than using literal values is clearer, and the makefiles include
both styles, so more work is needed to achieve consistency using either
approach.

> PS. I'd like Emacs to switch to a nonrecursive 'make' process, as this
> subsidiary $(MAKE) -C business is for the birds. We've made the switch
> for other GNU projects and it's been a win. This is not a new idea; see:
>
> Miller P. Recursive Make considered harmful. AAUGN J of AUUG.
> 1998;19(1):14-25. https://grosskurth.ca/bib/1997/miller.pdf

This is a good idea, and should result in better dependency tracking and
possibly faster parallel builds. Please make sure it works for in tree
and out of tree builds, as both are useful.

    AndyM