Re: Merging native-comp and pgtk

[Stefan Kangas]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> I've got one question about how things are compiled that I meant to ask
> but forgot: Why is AOT not the default, and why does the native-comp
> branch do compilation on-the-fly in the background?

For me, it is a happy middle-ground: I do not need to make
NATIVE_FULL_AOT=1 (which is slower) but can still rely on getting the
performance increase automagically.

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Tassilo Horn <tsdh@gnu.org> writes:
>
>> Given that the ELN compilation takes quite some time, I think that's one
>> major reason.  Another thing is that the on-the-fly compilation also
>> compiles all ELPA packages and even packages just residing somewhere on
>> my customized load-path which aren't accessible at emacs build time.
>
> That's nice, but it's unusual for Emacs to do something like that.
>
> When installing an ELPA package, Emacs byte-compiles the files, right?
> So it should do .eln compilation at the same time, in my opinion.

It would have some benefits I guess, but it would slow down package
installation.  Whatever we do, it would be nice to avoid that.

On the nativecomp branch, package.el requests to do the .eln compilation
asynchronously in the background.  AFAIU, if Emacs is killed before the
package is compiled, it will be put back in the compilation queue after
the package is used in a subsequent session.

The drawback is that we get compilation warnings pop up every now and
then, which is arguably somewhat disruptive.  But this could be improved
upon, I think.  For example, I'm not sure users need to see all warnings
by default for installed packages even in the byte-compilation case.  We
could perhaps have an option to enable these warnings for the genuine
sticklers out there.  (I for one would definitely turn it on...)