(gdb) run
Starting program: /usr/bin/php index.php
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".

Program received signal SIGSEGV, Segmentation fault.
xdebug_debugger_set_program_name (filename=0x0) at /tmp/pear/temp/xdebug/src/debugger/debugger.c:104
104                     XG_DBG(context).program_name = zend_string_copy(filename);
(gdb) bt full
#0  xdebug_debugger_set_program_name (filename=0x0) at /tmp/pear/temp/xdebug/src/debugger/debugger.c:104
No locals.
#1  0x00007ffff508f8ec in xdebug_execute_user_code_begin (execute_data=<optimized out>) at /tmp/pear/temp/xdebug/src/base/base.c:731
        op_array = 0x555555dd7d60
        edata = 0x0
        fse = <optimized out>
#2  0x00005555558d4a59 in ?? ()
No symbol table info available.
#3  0x00005555558acd00 in zend_execute ()
No symbol table info available.
#4  0x000055555583cd20 in zend_execute_scripts ()
--Type <RET> for more, q to quit, c to continue without paging--<RET>
No symbol table info available.
#5  0x00005555557d79ea in php_execute_script ()
No symbol table info available.
#6  0x0000555555925e5e in ?? ()
No symbol table info available.
#7  0x000055555567c097 in ?? ()
No symbol table info available.
#8  0x00007ffff74e8d90 in __libc_start_call_main (main=main@entry=0x55555567bcc0, argc=argc@entry=2, argv=argv@entry=0x7fffffffe058) at ../sysdeps/nptl/libc_start_call_main.h:58
        self = <optimized out>
        result = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {0, 4536979451957479101, 140737488347224, 93824993443008, 93824997203416, 140737354125376, -4536979453019420995, -4536962817066006851}, 
              mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x7fffffffe058, 0x0}, data = {prev = 0x0, cleanup = 0x0, canceltype = -8104}}}
        not_first_call = <optimized out>
#9  0x00007ffff74e8e40 in __libc_start_main_impl (main=0x55555567bcc0, argc=2, argv=0x7fffffffe058, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe048)
    at ../csu/libc-start.c:392
No locals.
#10 0x000055555567d1f5 in _start ()
No symbol table info available.