[php-src] Issue #8581: Segfault with observer API on max execution time during php -r

Issue: https://github.com/php/php-src/issues/8581 Author: rioderelfte ### Description The following command: ```sh sapi/cli/php -n \ -d 'max_execution_time=1' \ -d 'zend_test.observer.enabled=1' \ -d 'zend_test.observer.observe_all=1' \ -r 'echo "test\n"; crc32("test"); for (;;) {}' ``` Resulted in this output: ``` <!-- init 'Command line code' --> <file 'Command line code'> test Fatal error: Maximum execution time of 1 second exceeded in Command line code on line 1 zsh: bus error sapi/cli/php -n -d 'max_execution_time=1' -d 'zend_test.observer.enabled=1' - ``` The execution results in a bus error instead of a segmentation fault, since the address which is jumped to is not properly aligned. While debugging this I also saw segmentation faults from time to time. I expect neither a bus error nor a segmentation fault to occur, when executing that command. Here is the output of lldb: ``` (lldb) run Process 92890 launched: '/Users/florian/projects/php/php-src/sapi/cli/php' (arm64) <!-- init 'Command line code' --> <file 'Command line code'> test Fatal error: Maximum execution time of 1 second exceeded in Command line code on line 1 Process 92890 stopped * thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=257, address=0x800000017c9e6865) frame #0: 0xffff80017c9e6865 error: memory read failed for 0xffff80017c9e6800 Target 0: (php) stopped. (lldb) bt * thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=257, address=0x800000017c9e6865) * frame #0: 0xffff80017c9e6865 frame #1: 0x00000001002a9ee0 php`zend_observer_fcall_end(execute_data=0x0000000101212020, return_value=0x0000000000000000) at zend_observer.c:220:3 [opt] frame #2: 0x00000001002a9fdc php`zend_observer_fcall_end_all at zend_observer.c:240:4 [opt] frame #3: 0x0000000100192a54 php`php_request_shutdown(dummy=0x0000000000000000) at main.c:1798:3 [opt] frame #4: 0x00000001002f1a54 php`do_cli(argc=10, argv=0x0000600002600120) at php_cli.c:1135:3 [opt] frame #5: 0x00000001002f0114 php`main(argc=<unavailable>, argv=<unavailable>) at php_cli.c:1367:18 [opt] frame #6: 0x00000001005ad088 dyld`start + 516 (lldb) frame select 1 php was compiled with optimization - stepping may behave oddly; variables may not be available. frame #1: 0x00000001002a9ee0 php`zend_observer_fcall_end(execute_data=0x0000000101212020, return_value=0x0000000000000000) at zend_observer.c:220:3 [opt] 217 218 zend_observer_fcall_end_handler *possible_handlers_end = handler + zend_observers_fcall_list.count; 219 do { -> 220 (*handler)(execute_data, return_value); 221 } while (++handler != possible_handlers_end && *handler != NULL); 222 223 if (first_observed_frame == execute_data) { ``` The output was generated on the current PHP-8.1 branch (commit dd89acaf4985fa21ebd6cc9b09615ef6b0a719fc). So far I only was able to reproduce the problem with php -r – not by executing a PHP file. ### PHP Version PHP 8.1.7 ### Operating System Mac OS X 12.3.1 (ARM)