Subject: Re: bug#46495: 28.0.50; [native-comp] Build fails for 32bit --with-wide-int

From: Andrea Corallo <[email-masked]>
Date: Mon, 29 Mar 2021 20:46:27 +0000

David Malcolm <[email-masked]> writes:

> On Mon, 2021-03-29 at 19:59 +0300, Eli Zaretskii wrote:
>> > From: Andrea Corallo <[email-masked]>
>> > Cc: [email-masked], [email-masked]
>> > Date: Mon, 29 Mar 2021 16:15:56 +0000
>> > 
>> > >   
>> > > https://sourceware.org/pipermail/gdb-patches/2021-March/177334.html
>> > > 
>> > > Is that possible?
>> > 
>> > Well if this is what you observe it certainly can be.  There might
>> > very
>> > well be something in how/what libgccjit generates that is causing
>> > this
>> > difference.
>> 
>> David, can you please chime in and help us understand what is going
>> on
>> here?
>
> In theory, libgccjit uses the same code-generation code and the same
> debuginfo-generation code as a regular gcc invocation.
>
> Some ideas:
>
> (a) Is libgccjit being invoked multiple times in-process?
> If so, I wonder if you're running into a latent bug in state-handling
> in libgccjit that's affecting either code generation or debuginfo
> generation.  Maybe something isn't being reset that should have been?
>
> Is there a way to get emacs to only do one libgccjit context
> compilation per process, and see if that affects things?

Hi Dave,

libgccjit here is invoked once.

> (b) Alternatively, maybe a simple bug in libgccjit that affects the
> first in-process invocation?

Shouldn't this likely affect configurations other than Windows i386?

> (c) Alternatively, maybe a bug in the emacs jit stuff that's corrupting
> the stack somehow?

I think as suggested compiling a simple function on Eli's system like
the hello word may give a strong indication on if this is Emacs related
or not.

Regards

  Andrea