Description:
------------
Since updating to PHP 5.6 we got random segmentation faults in our PHP-FPM environment. I have not been able to reproduce this.
The amount of segmentation faults raised to a very noticable level and I configured PHP to save core dumps to be able to investigate further. After just this configuration change, the amount of segmentation faults has massively reduced, but I have gotten the same error 3 times in 3 days (see 1st backtrace) and another error today (see 2nd backtrace).



Our Environment:
Suhosin patch applied

Extensions:
apcu.so
bcmath.so
bz2.so
calendar.so
ctype.so
curl.so
dom.so
ftp.so
gd.so
geoip.so
gettext.so
gmp.so
iconv.so
imap.so
intl.so
json.so
mbstring.so
mcrypt.so
mysqli.so
mysql.so
opcache.so
openssl.so
pcntl.so
posix.so
shmop.so
soap.so
sockets.so
suhosin.so
sysvmsg.so
sysvsem.so
sysvshm.so
xmlreader.so
zip.so
zlib.so





Actual result:
--------------
Backtrace 1 (3x):
Program terminated with signal 11, Segmentation fault.
#0  0x00007fac9d049acf in instanceof_function_ex (instance_ce=0x7facaaa559c8, ce=ce@entry=0x7facaa7747a0, interfaces_only=interfaces_only@entry=0 '\000') at /usr/src/debug/php-5.6.3/Zend/zend_operators.c:1880
1880                    if (instanceof_function(instance_ce->interfaces[i], ce TSRMLS_CC)) {
(gdb) bt
#0  0x00007fac9d049acf in instanceof_function_ex (instance_ce=0x7facaaa559c8, ce=ce@entry=0x7facaa7747a0, interfaces_only=interfaces_only@entry=0 '\000') at /usr/src/debug/php-5.6.3/Zend/zend_operators.c:1880
#1  0x00007fac9d049a87 in instanceof_function (instance_ce=<optimized out>, ce=ce@entry=0x7facaa7747a0) at /usr/src/debug/php-5.6.3/Zend/zend_operators.c:1899
#2  0x00007fac90ae063f in soap_error_handler (error_num=8192, error_filename=0x7fac9d10af3b "Unknown", error_lineno=0, 
    format=0x7fac9d143240 "Automatically populating $HTTP_RAW_POST_DATA is deprecated and will be removed in a future version. To avoid this warning set 'always_populate_raw_post_data' to '-1' in php.ini and use the php://input"..., args=0x7fffca0cda00) at /usr/src/debug/php-5.6.3/ext/soap/soap.c:2148
#3  0x00007fac9d04e61c in zend_error (type=8192, 
    format=0x7fac9d143240 "Automatically populating $HTTP_RAW_POST_DATA is deprecated and will be removed in a future version. To avoid this warning set 'always_populate_raw_post_data' to '-1' in php.ini and use the php://input"...) at /usr/src/debug/php-5.6.3/Zend/zend.c:1145
#4  0x00007fac9cff2067 in php_default_post_reader () at /usr/src/debug/php-5.6.3/main/php_content_types.c:75
#5  php_default_post_reader () at /usr/src/debug/php-5.6.3/main/php_content_types.c:51
#6  0x00007fac9cfedf8d in sapi_read_post_data () at /usr/src/debug/php-5.6.3/main/SAPI.c:247
#7  sapi_activate () at /usr/src/debug/php-5.6.3/main/SAPI.c:482
#8  0x00007fac9cfe4e3c in php_request_startup () at /usr/src/debug/php-5.6.3/main/main.c:1634
#9  0x00007fac9cea4ac1 in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/php-5.6.3/sapi/fpm/fpm/fpm_main.c:1898




Backtrace 2 (1x):
Program terminated with signal 11, Segmentation fault.
#0  0x00007fac9d075e08 in zend_std_object_get_class (object=0x7facaab99a08) at /usr/src/debug/php-5.6.3/Zend/zend_object_handlers.c:1528
1528            return zobj->ce;
(gdb) #0  0x00007fac9d075e08 in zend_std_object_get_class (object=0x7facaab99a08) at /usr/src/debug/php-5.6.3/Zend/zend_object_handlers.c:1528
#1  0x00007fac90ae0634 in soap_error_handler (error_num=8192, error_filename=0x7fac9d10af3b "Unknown", error_lineno=0, 
    format=0x7fac9d143240 "Automatically populating $HTTP_RAW_POST_DATA is deprecated and will be removed in a future version. To avoid this warning set 'always_populate_raw_post_data' to '-1' in php.ini and use the php://input"..., args=0x7fffca0cda00) at /usr/src/debug/php-5.6.3/ext/soap/soap.c:2148
#2  0x00007fac9d04e61c in zend_error (type=8192, 
    format=0x7fac9d143240 "Automatically populating $HTTP_RAW_POST_DATA is deprecated and will be removed in a future version. To avoid this warning set 'always_populate_raw_post_data' to '-1' in php.ini and use the php://input"...) at /usr/src/debug/php-5.6.3/Zend/zend.c:1145
#3  0x00007fac9cff2067 in php_default_post_reader () at /usr/src/debug/php-5.6.3/main/php_content_types.c:75
#4  php_default_post_reader () at /usr/src/debug/php-5.6.3/main/php_content_types.c:51
#5  0x00007fac9cfedf8d in sapi_read_post_data () at /usr/src/debug/php-5.6.3/main/SAPI.c:247
#6  sapi_activate () at /usr/src/debug/php-5.6.3/main/SAPI.c:482
#7  0x00007fac9cfe4e3c in php_request_startup () at /usr/src/debug/php-5.6.3/main/main.c:1634
#8  0x00007fac9cea4ac1 in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/php-5.6.3/sapi/fpm/fpm/fpm_main.c:1898