Re: nativecomp and throw/catch across files

[Andrea Corallo via "Emacs development discussions." <emacs-devel@gnu.org>]

Aaron Jensen <aaronjensen@gmail.com> writes:

> Hi there,
>
> I've been trying out the nativecomp branch and I use straight.el as my
> package manager.
>
> One of the things that it does is throw when it detects that its own
> compiled bytecode has changed. It does this from within straight.el:
>
> (eval
>  `(unless (equal
>            (emacs-version)
>            ,(eval-when-compile (emacs-version)))
>     (throw 'emacs-version-changed nil)))
>
> https://github.com/raxod502/straight.el/blob/2d407bccd9378f1d5218f8ba2ae85c6be73fbaf1/straight.el#L45-L49
>
> It then catches within bootstrap.el, which loads straight.el:
>
> (catch 'emacs-version-changed
>         ;; straight.el has a fun hack that throws
>         ;; `emacs-version-changed' if the version of Emacs has changed
>         ;; since the last time it was byte-compiled. This prevents us
>         ;; from accidentally loading invalid byte-code, hopefully.
>         (load (expand-file-name (concat straight.el "c")
>                                 default-directory)
>               nil 'nomessage 'nosuffix)
>         (setq emacs-version-changed nil))
>
> https://github.com/raxod502/straight.el/blob/2d407bccd9378f1d5218f8ba2ae85c6be73fbaf1/bootstrap.el#L47-L54
>
> Unfortunately, this doesn't work with nativecomp. It claims that
> there's no matching catch when a throw actually happens.
>
> Warning (initialization): An error occurred while loading
> ‘/Users/aaronjensen/.emacs.d/early-init.el’:
>
> No catch for tag: emacs-version-changed, nil
>
>
> To reproduce, you should be able to use the bootstrap code:
> https://github.com/raxod502/straight.el#bootstrapping-straightel
>
> Then recompile emacs (which changes the value of emacs-version) and run again.
>
> I tried narrowing it down to just a try/catch in two different files
> and that worked, so there must be something more peculiar going on
> here.

Hi Aaron,

is there a corresponding issue open in straight?  Perhaps straight
developers can narrow down the issue and suggest a minimal reproducer in
case this is a real issue on our side.

Thanks

  Andrea