bug#46256: [feature/native-comp] AOT eln files ignored if run from build tree

[Andy Moreton]

On Sun 28 Feb 2021, Eli Zaretskii wrote:

>> From: Andy Moreton <andrewjmoreton@gmail.com>
>> Date: Sat, 27 Feb 2021 21:58:25 +0000
>> 
>> > I suspect that the issue may be with parallel builds (note the "-j8"
>> > above). Repeating the build with "-j1" appears to be building the
>> > missing .eln files as expected.
>> 
>> Now that the -j1 build has completed (without error), all of the lisp
>> files have been compiled AOT as expected, and running the resulting
>> emacs does not rebuild any of those .eln files.
>> 
>> So I think there are still some other issues with dependencies and
>> handling parallel builds, but this bug has been fixed.
>
> Hmm... what would be the reason for parallel builds not work well on
> MS-Windows? file sharing issues?
>
> Does the async native compilation use temporary files, and if so, do
> they reside in the same directory when multiple compilations are
> running?

I've tried a few builds from a clean tree (after "git clean -xdf") and
have note  been able to reproduce this parallel build problem again.

Do let me know if there are any steps I should take to help diagnose it
if it does reproduce again.

    AndyM