Re: The emacs-28 release branch has been created

[Andrea Corallo]

Eli Zaretskii <eliz@gnu.org> writes:

>> From: Andrea Corallo <akrl@sdf.org>
>> Cc: kbrown@cornell.edu, emacs-devel@gnu.org
>> Date: Mon, 04 Oct 2021 16:15:35 +0000
>> 
>> Okay I see what's the issue.  In `comp-final' we spawn a child process
>> to run the final pass or not discriminating on the `byte+native-compile'
>> var.  This is wrong cause this is not bound when using
>> `batch-native-compile'.
>
> Can you explain (or guess) why this caused the specific problem it did
> (i.e. truncation of some temporary file, AFAIU), and why only in that
> single .el file?

No idea so far, needs further investigation.

> Also, your fix introduces a new special variable for that, so I guess
> it means the problem is not specific to all batch native-compilations,
> only to some?

I guess the problem affects all compilations where we spawn a child
process to compile and where we compile something like the reproducer
where we have (probably) a very long const vector(?).  I'll report when
I have more details.

> If so, what is special in byte+native-compile and
> batch-native-compile that they require not to spawn a child process?

Nothing special, we used to discriminate if we wanted to spawn a child
process using `byte+native-compile', but this worked only for
byte+native-compile' and not for `batch-native-compile'.  For both these
two function we do not want to spawn a child process as its really not
necessary, so my fix.

Best Regards

  Andrea