008+ prompt> ASAN:DEADLYSIGNAL
009+ =================================================================
010+ ==29572==ERROR: AddressSanitizer: SEGV on unknown address 0x7f4c6281f030 (pc 0x562ead0ebebd bp 0x562ead903840 sp 0x7fffde91d5a0 T0)
011+ ==29572==The signal is caused by a WRITE memory access.
012+ #0 0x562ead0ebebc in ZEND_ASSIGN_SPEC_CV_CONST_RETVAL_UNUSED_HANDLER /home/zsw/Documents/project/php/php-7.2.6/Zend/zend_vm_execute.h:37329
013+ #1 0x562ead292355 in zend_vm_call_opcode_handler /home/zsw/Documents/project/php/php-7.2.6/Zend/zend_vm_execute.h:69305
014+ #2 0x562ead2b0590 in phpdbg_execute_ex /home/zsw/Documents/project/php/php-7.2.6/sapi/phpdbg/phpdbg_prompt.c:1900
015+ #3 0x562ead290a9a in zend_execute /home/zsw/Documents/project/php/php-7.2.6/Zend/zend_vm_execute.h:63760
016+ #4 0x562ead2acc12 in phpdbg_do_run /home/zsw/Documents/project/php/php-7.2.6/sapi/phpdbg/phpdbg_prompt.c:942
017+ #5 0x562ead2e11a4 in phpdbg_internal_stack_execute /home/zsw/Documents/project/php/php-7.2.6/sapi/phpdbg/phpdbg_cmd.c:703
018+ #6 0x562ead2e11a4 in phpdbg_stack_execute /home/zsw/Documents/project/php/php-7.2.6/sapi/phpdbg/phpdbg_cmd.c:733
019+ #7 0x562ead2af63e in phpdbg_interactive /home/zsw/Documents/project/php/php-7.2.6/sapi/phpdbg/phpdbg_prompt.c:1631
020+ #8 0x562eacb5cdaa in main /home/zsw/Documents/project/php/php-7.2.6/sapi/phpdbg/phpdbg.c:2001
021+ #9 0x7f4c65aaa1c0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x211c0)
022+ #10 0x562eacb5e1f9 in _start (/home/zsw/Documents/project/php/php-7.2.6/sapi/phpdbg/phpdbg+0x2271f9)
023+
024+ AddressSanitizer can not provide additional info.
025+ SUMMARY: AddressSanitizer: SEGV /home/zsw/Documents/project/php/php-7.2.6/Zend/zend_vm_execute.h:37329 in ZEND_ASSIGN_SPEC_CV_CONST_RETVAL_UNUSED_HANDLER
008- prompt> [Breaking on watchpoint $b]
009- Old value:
010- New value: Array ([0] => 1)
011- >00006: unset($b);
012- 00007: $b = 2;
013- 00008:
014- prompt> [Breaking on watchpoint $b]
015- Old value inaccessible or destroyed
016- New value:
017- >00007: $b = 2;
018- 00008:
019- prompt> [Breaking on watchpoint $b]
020- Old value:
021- New value: 2
022- >00008:
023- prompt> [$b has been removed, removing watchpoint recursively]
024- [Script ended normally]
025- prompt>
026+ ==29572==ABORTING