Re: Sharing native-lisp system load-path between builds

[Björn Bidar]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Björn Bidar <bjorn.bidar@thaodan.de>
>> Date: Mon, 26 Jun 2023 03:14:17 +0300
>> 
>> I'm building Emacs master for OpenSUSE to provide testing.
>> OpenSUSE packaging packages Emacs so that they have three builds with
>> different feature sets: X11 without GTK, GTK and one build just without
>> X11 or GTK.
>> 
>> This helps different users to chose their preferred builds and keeps
>> build workers small for Emacs packages build.
>> 
>> The packages share the elisp, native-lisp ahead of time compilations and
>> docs.
>> 
>> Recently the native-lisp load path changed to change per Emacs
>> executable.
>
> It isn't a recent change, at least not in principle.

What could have change this?

>> I don't know the exact commit when this changed but it was
>> between ref 3c8167ec0f9647e6fc33e65b0a0324f96cb795ee and
>> d46a2fa319808963bbe8d3a90e7dbb13fcd844f5.
>> 
>> Now my questions: Is this a bug or can a different hash be used to
>> determine the system load-path? It is very useful to precompile the
>> lisp code once per emacs builds that share the same code.
>
> It's impossible to share native-compiled *.eln files between different
> builds, because they depend on the primitives compiled into the build
> and on the architecture of the host CPU.

> So you must have a separate directory for each build configuration,
> and any significant change in the Emacs C code will require
> recompilation of all the *.eln files.

Each build configuration is 100% the same except the optional
dependencies they are build with.

There's no change to any source they are build one after the other.

See the spec file here:
https://build.opensuse.org/package/view_file/home:Thaodan:emacs/emacs/emacs.spec?expand=1