bug#41357: 28.0.50; GC may miss to mark calle safe register content

[Andrea Corallo]

Paul Eggert <eggert@cs.ucla.edu> writes:

> On 5/17/20 9:40 AM, Andrea Corallo wrote:
>> I think this is a real bug that we have in the codebase (emacs-27
>> included).
>
> Thanks for all the detective work! Your analysis is correct and your patch 
> looks
> good. I've always been suspicious of that code, and it looks like you've
> confirmed my suspicions.
>
> The only question in my mind is whether to install the patch into the emacs-27
> branch or the master branch. Given Eli's problems with stability in emacs-27
> (see Bug#41321), I'm inclined to think the former, as the bug could explain 
> the
> problems Eli is observing.

Hi Paul,

I'm glad you liked the investigation.

I've pushed the fix on master as Eli suggested, feel free to improve it
in case.

I hope a different agreement can be found for 27, in case I'll port it
there.

Thanks!

  Andrea

-- 
akrl@sdf.org