Re: Finalizing 'inhibit-automatic-native-compilation'

[Aymeric Agon-Rambosson]

Le mardi 7 février 2023 à 13:56, Andrea Corallo <akrl@sdf.org> a 
écrit :

> Advising primitives is a dangerous action, it can lead the Emacs
> machinery to malfunction anytime, these misbehaviors are not 
> documented
> and can change from version to version as from configuration to
> configuration.  The programmer who advises or redefines a 
> primitive
> should be ready to understand the underlying machinery and work 
> out
> potential issues (as it was done in this case).

Agreed. Advising primitives was already frowned upon even before 
native compilation, it always was dangerous. However, tests have 
been doing this for quite some time.

> I don't think this is a native comp specific problem, I'm sure 
> one can
> find similar examples also on non native comp enabled Emacses.

This is very possible, but in the cases I mentioned (projectile, 
yasnippet and beginend), the test failures or errors disappeared 
when we excluded the primitives from trampoline 
compilation. Sometimes, like in the projectile case, we were able 
to track exactly what happened, and offer a convincing explanation 
of the fix along with it. But that is not always the case : I have 
offered patches for yasnippet and beginend that solve test 
failures, and I can not completely justify them with anything 
other than "it solves the issue I'm presenting". On top of that, 
said issue has probably not been encountered by the upstream 
maintainer (maybe because they had the trampolines already 
available beforehand), we uncovered it with our specific build 
setting. Those patches may or may not be accepted by the upstream 
maintainers. My point being, the issues caused by widespread 
primitive advice in the test suites of addon packages, that we 
have just uncovered with trampoline compilation and our peculiar 
build environment, will probably be there for a long time. And I 
agree that this is the job of upstream maintainers to patch them, 
but they will be probably be very slow to fix them.

These examples were meant as an illustration of why we might want 
to exclude primitives from trampoline compilation in the 
(potentially quite long) meantime.

Best,

Aymeric