Re: disable automatic native-compilation?

[Ken Brown <kbrown@cornell.edu>]

On 7/10/2022 10:39 PM, Lynn Winebarger wrote:
> On Sun, Jul 10, 2022, 9:53 PM Ken Brown <kbrown@cornell.edu 
> <mailto:kbrown@cornell.edu>> wrote:
> 
>     On 7/10/2022 5:54 PM, Ken Brown wrote:
>      > Native compilation is unusable on 32-bit Cygwin, and this is reflected in
>     the
>      > configure script.  (See the --with-cygwin32-native-compilation configure
>     option.)
>      >
>      > In the 64-bit case, Achim Gratz's autorebase postinstall script takes
>     care of
>      > rebasing the .eln files on a regular basis, provided the user has set
>     things up
>      > appropriately.  Instructions can be found in the announcement at
>      >
>      > https://cygwin.com/pipermail/cygwin-announce/2022-April/010529.html
>     <https://cygwin.com/pipermail/cygwin-announce/2022-April/010529.html>
>      >
>      > In the 3 months since I sent that announcement, I have not heard from a
>     single
>      > Cygwin user about rebase issues.  This might simply mean that very few users
>      > have tried the native compilation release.
> 
> 
> Will do, but could you include the details of the announcement in the emacs 
> source distribution somewhere, as is done for the other variants with specific 
> instructions?  I'm only incidentally building it in a cygwin environment - it 
> didn't even occur to me to check the general cygwin mailing list.

Yes, I'll add something to etc/PROBLEMS unless you or Eli can suggest a better 
place.

>      >
>      > I myself use that release daily, and I can only recall one instance in
>     which I
>      > saw a fork failure and had to exit emacs and rebase.
>      >
>      > In summary, I would say that native compilation is usable with very
>     occasional
>      > minor annoyances on 64-bit Cygwin.  But I doubt if I will ever make it the
>      > default Cygwin build, simply because I don't want to be inundated with
>     emails
>      > from people who haven't read the release announcement.
> 
>     Lynn,
> 
>     Rereading your earlier message about problems during package installation, I
>     see
>     I didn't really respond to that.  But it has nothing to do with the present
>     bug,
>     so please make a fresh bug report and give full details.  And please follow the
>     instructions in the announcement I cited.  If you're working in your own build
>     of Cygwin emacs that you haven't installed, you might also have to add its
>     native-lisp directory to
> 
>         /var/lib/rebase/userpath.d/<username>
> 
> 
> I am doing exactly what you surmised, running a build I haven't installed - in 
> fact that I built with --prefix=/does/not/exist/ to ensure system installed 
> site-lisp files will not get injected into the load-path while doing do.  So 
> I'll try that first.  Although I think the packages generating the fork failures 
> should be going into the cache in my home directory.

That's true, but Cygwin's autorebase facility needs to know about *all* .eln 
files that might be used, in order to try to maintain a conflict-free set of 
base addresses.

And I forgot to say that after you've created 
/var/lib/rebase/userpath.d/<username> with the appropriate paths, you should 
shut down all Cygwin processes and run Cygwin's setup program.  (You don't have 
to install anything; this is just to let the autorebase postinstall script run.)

> If there are still issues, did you mean to log a bug with cygwin or emacs?

I meant emacs.  Thanks.

Ken