Re: Need help finding segfault in php 7

Hey: On Thu, Aug 13, 2015 at 8:36 PM, James Gilliland <neclimdul@gmail.com> wrote: > So I've been trying for a couple days to narrow down this bug: > https://bugs.php.net/bug.php?id=70242 > > I can consistently recreate it with a complex test, but I have thus far not > been able to find a pattern that helps me narrow down to a test script. I > thought maybe I could reach out and see if I could get some help > understanding what is happening in php and see if that has any clues. > > > Seemingly important facts I've found digging through in gdb. > 1) The connection related pointers on the stmt are already freed when the > fault happens. It looks like the statement is being freed after the > connection and the if (S->H->server) { surrounding the failing code is not > sufficient to catch this > 2) The trace has a spl_iterator in it so it seems like that is holding on > to the stmt pointer. There is a IteratorIterator used on a PDO stmt in the > code. But also in a lot of other non-triggering seemingly identical code > and I haven't been able to get this to work. > 3) The code in shutdown_executor that is triggering this is the 6th block > of cleanups which seems to support 1). It is the block without any > documentation which is sort of my luck in this. > > I'm guessing there is some way I need to trick a object to hold onto a > reference through the other cleanups or something or trigger some sort of > reference counter quirk but I just can't find it. Any help is appreciated. thanks for the ssh access , I finally get the reason of this bug.. I get a simple reproduce script and quick fix. all listed in https://bugs.php.net/bug.php?id=70272&thanks=1 @dmitry: do you see a better solution ? thanks -- Xinchen Hui @Laruence http://www.laruence.com/