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Subject: [Bug bootstrap/84402] [meta] GCC build system: parallelism bottleneck
Date: Thu, 02 Jun 2022 22:05:09 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D84402

--- Comment #47 from Segher Boessenkool <segher at gcc dot gnu.org> ---
(In reply to Sam James from comment #46)
> Even partially making the build less recursive would likely help a fair b=
it.

It will help a bit, sure, but not nearly as much as you perhaps hope for.

There are quite a few "synchronisation" points where nothing after it can be
done until everything before it has been done.  Partly this is just because
we have a three-stage bootstrap, but also there are some generator programs
that everything else depends on (on its output that is), and those are real
chokepoints.

Also, recursive make is a scourge of humanity, for sure, but fixing this has
to be done in autoxxxx first and foremost.=