Description:
------------
I use PHP 5.5.24 + php-fpm + opcache.
CPU is Intel(R) Xeon(R) CPU X5650  @ 2.67GHz.
Memory is 4GB.
I apply some original patches and use original extensions.
My application can not run without them,
because they are closely related with it.

Sometimes, following logs are recorded on php-fpm.log:
[13-Apr-2015 01:14:34] WARNING: [pool www] child 30683 said into stderr: "zend_mm_heap corrupted"
[13-Apr-2015 01:14:34] WARNING: [pool www] child 30683 exited with code 1 after 1220.432552 seconds from start
[13-Apr-2015 01:14:34] NOTICE: [pool www] child 3481 started

This error occurs on random.
It is hard to find a reproducing code.

My opcache config is following:
[opcache]
opcache.memory_consumption=384
opcache.interned_strings_buffer=8
opcache.max_accelerated_files=200
opcache.revalidate_freq=60
opcache.fast_shutdown=1

When I change opcache.max_accelerated_files to 7000,
the frequency of "zend_mm_heap corrupted" decreases.
When I change opcache.max_accelerated_files to 60000,
"zend_mm_heap corrupted" does not occur.
# My application consists of 10000+ PHP files.

Expected result:
----------------
PHP-FPM process should not report "zend_mm_heap corrupted"

Actual result:
--------------
PHP-FPM process reports "zend_mm_heap corrupted" sometimes.

I try to get coredump with "--enable-debug".
but, this error does not reproduced it with "--enable-debug".
So, I modified L91 like this and built PHP:
https://github.com/php/php-src/blob/php-5.5.24/Zend/zend_alloc.c#L91
> #if ZEND_DEBUG && defined(HAVE_KILL) && defined(HAVE_GETPID)
> ↓
> #if defined(HAVE_KILL) && defined(HAVE_GETPID)

Now, I can get coredump.

GDB backtrace:

GNU gdb (Ubuntu 7.7.1-0ubuntu5~14.04.2) 7.7.1
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License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
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Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
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For help, type "help".
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Reading symbols from /usr/local/php/sbin/php-fpm...done.
[New LWP 4688]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Core was generated by `php-fpm: pool www                                                       '.
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0x00007f6f84b7ffb7 in kill () from /lib/x86_64-linux-gnu/libc.so.6
(gdb) bt
#0  0x00007f6f84b7ffb7 in kill () from /lib/x86_64-linux-gnu/libc.so.6
#1  0x000000000042f9ab in zend_mm_panic (message=0xab36ca "zend_mm_heap corrupted") at /home/build/php/php-5.5.24/Zend/zend_alloc.c:92
#2  0x000000000072f188 in zend_mm_remove_from_free_list (heap=<optimized out>, mm_block=<optimized out>)
    at /home/build/php/php-5.5.24/Zend/zend_alloc.c:800
#3  0x000000000072f3ac in _zend_mm_free_int (heap=0x1792330, p=0x256ea08) at /home/build/php/php-5.5.24/Zend/zend_alloc.c:2106
#4  0x0000000000763968 in zend_hash_destroy (ht=0xe45690 <compiler_globals+272>) at /home/build/php/php-5.5.24/Zend/zend_hash.c:560
#5  0x0000000000733428 in shutdown_compiler () at /home/build/php/php-5.5.24/Zend/zend_compile.c:243
#6  0x0000000000755ee5 in zend_deactivate () at /home/build/php/php-5.5.24/Zend/zend.c:949
#7  0x00000000006f779d in php_request_shutdown (dummy=dummy@entry=0x0) at /home/build/php/php-5.5.24/main/main.c:1812
#8  0x0000000000430ff4 in main (argc=<optimized out>, argv=<optimized out>) at /home/build/php/php-5.5.24/sapi/fpm/fpm/fpm_main.c:1981