Re: Add a configure option for NATIVE_FULL_AOT?

[Eli Zaretskii]

> Date: Wed, 18 Aug 2021 18:22:16 +0200
> From: tomas@tuxteam.de
> Cc: emacs-devel@gnu.org
> 
> When the user wants to change a distribution-specific .el, the default
> way to do it would be to make a user-writable copy somewhere in a
> user-controlled directory (ISTR there was a mechanism doing this
> semi-transparently, but I may be confused). If `load-path' is set up
> correctly, the user's variant takes precedence. Same would go for
> .eln files resp. native-comp-eln-load-path, right?

Nominally, yes.  But then you have 2 copies of the same .eln file, in
2 different places.  That's got to confuse people and perhaps create
hard-to-debug situations where Emacs behaves erratically.

> > We actually do use native-comp-eln-load-path to also decide where to
> > store the *.eln files, but that uses a simplistic heuristic that
> > treats the last element of the list specially.  The heuristic is
> > hard-coded in several places, so not easily overridden.
> 
> Oh, the /last/ element, i.e. the one with the least precedence is the
> one where .eln files are stored? There goes my house of cards.
> Interesting ;-)

The preloaded *.eln files are stored there, yes.  How else would you
arrange for them to be of the least precedence, when lists are
generally searched head to tail?