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Message-ID: <7.0.0.16.2.20051208182336.05abbcb0@zend.com>
Date: Thu, 08 Dec 2005 18:24:17 -0800
To: david_oren@excite.com,internals@lists.php.net
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Subject: Re: [PHP-DEV] Bugs in zend.c and zend_compile.c in ZTS mode
From: andi@zend.com (Andi Gutmans)

Hi David,

Would be happy to take a look at these bugs.
Any chance you can send a short reproducing script?

Thanks,

Andi

At 12:15 AM 12/8/2005, David Oren wrote:

>Hello all,
>
>
>
>I have recently switched to PHP 5.1, and have been encountering 
>crashes during shutdown. I have tried delving into the PHP code to 
>locate the source of the problems, and have discovered two issues, 
>both of which only happen when compiled with ZTS enabled.
>
>
>
>The first is very probably a bug.
>
>
>
>In zend_compile.c, in the zend_initialize_class_data function, 
>inside the #ifdef ZTS block, the following line can be found:
>
>
>
>     ce->static_members = (HashTable*)n;
>
>
>
>This casts an int variable, which denotes an index of the 
>static_members array, to a pointer. I assume what was meant is:
>
>
>
>     ce->static_members = (HashTable*) (CG(static_members)[n]);
>
>
>
>In addition, support for runtime declaration (handled by the if 
>block) is broken, as it will not work when CG(static_members) is 
>NULL and we're trying to add the first member, so the if block 
>should be followed by an else block similar to this one.
>
>
>
>     else if (!CG(static_members)) {
>
>         // n is probably 0 at this point
>
>         CG(last_static_member) = n+1;
>
>         CG(static_members) = (HashTable**)calloc(n+1, sizeof(HashTable*));
>
>     }
>
>
>
>If needed, I can provide a patch for this issue.
>
>
>
>The second issue _may_ be a bug, but I'm not familiar enough with 
>the Zend Engine internals to be certain.
>
>
>
>In zend.c, the zend_post_startup function unlinks the global (r/o) 
>copies of several tables, and creates fresh r/w copies for the startup threads.
>
>
>
> >From looking at the code, it would seem that the unlinking of the 
> persistent_list is NOT done cleanly: The persistent list of the 
> running thread is destroyed and reinitialized (by 
> executor_globals_ctor), and this is what the global_persistent_list 
> variable points to. In other words, the global persistent list is 
> shared with the startup thread.
>
>
>
>Again, in this case it _feels_ wrong, but this may also be what was intended.
>
>
>
>I hope I've managed to make sense, and I'd appreciate any feedback on this.
>
>
>
>Thanks,
>
>
>
>David Oren
>
>
>
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