bt.log

    #0  zend_hash_find (ht=ht@entry=0x7fffecea5278, key=key@entry=0x0)
        at /home/saitama/GitSrc/php-src/Zend/zend_hash.c:1929
    #1  0x00000000008f263b in zend_hash_find_ptr (key=0x0, ht=0x7fffecea5278)
        at /home/saitama/GitSrc/php-src/Zend/zend_hash.h:744
    #2  zend_std_get_static_property (ce=ce@entry=0x7fffecea5200, 
        property_name=property_name@entry=0x0, silent=silent@entry=0 '\000')
        at /home/saitama/GitSrc/php-src/Zend/zend_object_handlers.c:1332
    #3  0x0000000000936871 in zend_fetch_static_property_address (type=0, 
        op2_type=8 '\b', op2=..., varname_type=1 '\001', varname=0x7fffece6f2e0)
        at /home/saitama/GitSrc/php-src/Zend/zend_execute.c:2009
    #4  zend_fetch_static_prop_helper_SPEC_CONST_UNUSED (type=0)
        at /home/saitama/GitSrc/php-src/Zend/zend_vm_execute.h:7263
    #5  0x0000000000965ea0 in execute_ex (ex=0x7fffecea5278)
        at /home/saitama/GitSrc/php-src/Zend/zend_vm_execute.h:60130
    #6  0x00007fffedc2b9f5 in pthreads_execute_ex (data=<optimized out>)
        at /home/saitama/GitSrc/pthreads/php_pthreads.c:150
    #7  0x000000000089e5cc in zend_call_function (fci=0x7fffece1e030, 
        fci@entry=0x7fffed9febc0, fci_cache=fci_cache@entry=0x7fffed9febf8)
        at /home/saitama/GitSrc/php-src/Zend/zend_execute_API.c:817
    #8  0x00007fffedc37047 in pthreads_routine_run_function (
        object=object@entry=0x7fffeda6e240, connection=0x7fffece836c0, 
        work=work@entry=0x0) at /home/saitama/GitSrc/pthreads/src/object.c:479
    #9  0x00007fffedc3716a in pthreads_routine (routine=<optimized out>)

---Type <return> to continue, or q <return> to quit---
    at /home/saitama/GitSrc/pthreads/src/object.c:505
#10 0x00007ffff687f6ba in start_thread (arg=0x7fffed9ff700)
    at pthread_create.c:333
#11 0x00007ffff4cc43dd in clone ()
    at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109