bug#36649: 27.0.50; pure space and pdumper

[Pip Cet]

On Wed, May 12, 2021 at 7:44 PM Lars Ingebrigtsen <larsi@gnus.org> wrote:
> Eli Zaretskii <eliz@gnu.org> writes:
>
> > I don't know if this is an interesting configuration.  AFAIU,
> > "--with-dumping=none" means you run the CANNOT_DUMP version, which
> > doesn't dump Emacs at all.
>
> Ah, yes...  and in that case I guess there is no pure space?  Oh well, I
> guess somebody has to look into getting unexec working on Linux if we're
> to, er, see what the impact of pure space unexec would have been.  If it
> was working.  :-)

I had it working a while ago, just not using libc malloc(). AFAIU,
that's just incompatible with unexec() now.

(And it's still slightly but significantly faster building with
unexec() on Linux than building with pdumper, at least in contrived
benchmarks).

So, yes, I'd misunderstood Eli and thought he had objections to this
patch; if he doesn't, we should look into fixing the native-comp parts
and apply it :-)

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