Re: `make check -j` fails when building GNU Make from source

[Paul Smith]

On Mon, 2023-04-03 at 14:36 +0200, Alejandro Colomar wrote:
> -  Being part of the make targets, it would enable running them in
>    parallel, taking around 1/4th the time it takes now.

Up until this morning this could not work because all the tests run in
the same directory and they create temporary files, etc. that would
interfere with each other.

Since I implemented the "each test runs in a different directory"
today, it COULD work.  It would still require major changes to the test
driver, which is implemented to assume that it "owns" all the tests
(when you start it it cleans up everything from all previous runs etc.)

> -  If you run them several times, you only get rerun the ones that
>    failed (especially if you run with -k) or didn't yet run.  This
>    allows interrupting the job and restarting (as I did).

This is the point I already addressed: it's highly unlikely that you
run the tests "several times" without making some change that means you
should restart them all anyway.  The only time that would happen is if
(a) you killed them partway through like you did, which is extremely
unusual and I don't think supporting that situation is worth spending a
lot of effort on, or (b) you're developing a single test and want to
re-run just that one, in which case you can just invoke it directly
(you probably want to do this anyway since when you do rebuild make you
don't want to re-run everything).