Requirements for native-compile support

Requirements for native-compile support

[Eli Zaretskii]

Andrea,

Do we need libgccjit only for compiling to *.eln, or do we also need
it for loading and executing the *.eln files?

IOW, if Emacs was built with libgccjit, but the library isn't
available at run time, will Emacs still be able to load and run *.eln
files that were produced elsewhere (assuming the native code is
compatible with the platform where it will be run)?

Thanks.

Re: Requirements for native-compile support

[Andrea Corallo via Emacs development discussions.]

Eli Zaretskii <eliz@gnu.org> writes:

> Andrea,
>
> Do we need libgccjit only for compiling to *.eln, or do we also need
> it for loading and executing the *.eln files?
>
> IOW, if Emacs was built with libgccjit, but the library isn't
> available at run time, will Emacs still be able to load and run *.eln
> files that were produced elsewhere (assuming the native code is
> compatible with the platform where it will be run)?

We don't use libgccjit for loading elns file but we still have libgccjit
as a dependency because ATM Emacs may need to compile a trampoline if a
primitive is redefined or advised.  If it's important to support native
builds with no libgccjit available we should redesign this specific
mechanism.

Regards

  Andrea

Re: Requirements for native-compile support

[Eli Zaretskii]

> From: Andrea Corallo <akrl@sdf.org>
> Cc: emacs-devel@gnu.org
> Date: Mon, 10 May 2021 07:40:35 +0000
> 
> We don't use libgccjit for loading elns file but we still have libgccjit
> as a dependency because ATM Emacs may need to compile a trampoline if a
> primitive is redefined or advised.  If it's important to support native
> builds with no libgccjit available we should redesign this specific
> mechanism.

I don't have any evidence that we need to support such builds, I guess
we will hear from downstream distro maintainers if they are needed.

Thanks.