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Date: Fri, 14 Jun 2013 11:35:51 -0700
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Subject: Re: [PHP-DEV] Zend GC Recursion Elimination
From: rasmus@lerdorf.com (Rasmus Lerdorf)

On 06/14/2013 11:04 AM, Anthony Ferrara wrote:
> When you run that on current master, you get a segfault stemming from the
> zval_mark_grey() GC function.

This segfault, or at least a segfault in zval_mark_grey(), has been
reported a couple of times:

https://bugs.php.net/64868
https://bugs.php.net/64827
https://bugs.php.net/61968

> So not a huge win overall, but can be significant in cases...
> 
> What do you think? Is this worth pursuing further? is there a case I'm
> missing, or some other reason we shouldn't do this?

Since the reduced stack usage is likely to reduce the chances of hitting
this segfault, which if it is the same one as in the bug reports, it is
happening in the wild, then it is very much worthwhile to pursue this.

-Rasmus