Segfault using v5.0-beta1
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I used to compile v5.0-beta1 in Alpine docker container - PHP 7.1.14
Tested small scripts - works fine!
But once I started to profile Drupal I got segfault (not yet found how to get what is caused it)
The integration I'm working on is https://www.drupal.org/project/xhprof/issues/2945687
@andypost thanks for the report. can you check the syslog in the container with the segfault line? it should be something along the lines of php-fpm[32649]: segfault at 8 ip 00007f3d6192e84e sp 00007fff068fac90 error 4 in tideways_xhprof.so[7f3d61928000+18000]. if you have this, you can calculate the file+line or address in the objdump of the shared address where the segfault happend. I just need the line from you, then i can give you back more commands for debugging.
Other approach would be to install gdb into the container, modify php-fpm to generate core dumps and then analyze that, its a bit more work though and if you haven't done it before it will be quite tricky :)
Thanx for quick reply, checking
php_1 | [20-Feb-2018 19:21:46] WARNING: [pool app] child 9 exited on signal 11 (SIGSEGV - core dumped) after 15.137710 seconds from start
diggin how to get coredump in docker)
# echo '/tmp/coredump-%e.%p' > /proc/sys/kernel/core_pattern
ash: can't create /proc/sys/kernel/core_pattern: Read-only file system
Setting on host helped according guide and then I got it
https://ma.ttias.be/generate-php-core-dumps-segfaults-php-fpm/
@47172edfb79d:/tmp$ gdb /usr/sbin/php-fpm7 core.47172edfb79d.php-fpm7.1519158010
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Reading symbols from /usr/sbin/php-fpm7...(no debugging symbols found)...done.
[New LWP 359]
warning: Can't read pathname for load map: No error information.
Core was generated by `php-fpm: pool app '.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 tracing_callgraph_bucket_find (bucket=0x2, current_frame=current_frame@entry=0x7f22476e19b0, previous=previous@entry=0x7f22476e1960, key=key@entry=4720297052383811517)
at /srv/php-xhprof-extension-5.0-beta1/tracing.c:95
95 /srv/php-xhprof-extension-5.0-beta1/tracing.c: No such file or directory.
And now I got line tracing.c:95
kinda related? #45
Reading symbols from /usr/sbin/php-fpm7...(no debugging symbols found)...done.
[New LWP 359]
warning: Can't read pathname for load map: No error information.
Core was generated by `php-fpm: pool app '.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 tracing_callgraph_bucket_find (bucket=0x2, current_frame=current_frame@entry=0x7f22476e19b0, previous=previous@entry=0x7f22476e1960, key=key@entry=4720297052383811517)
at /srv/php-xhprof-extension-5.0-beta1/tracing.c:95
95 if (bucket->key == key &&
FYI I did build extension from master branch & looks it works fine! probably it's time to release second beta)