[root@asterisk1 ~]# gdb /usr/sbin/asterisk core.27740
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This GDB was configured as "x86_64-unknown-linux-gnu"...Using host libthread_db library "/lib64/tls/libthread_db.so.1".

Core was generated by `/usr/sbin/asterisk'.
Cannot access memory at address 0x2b06a9b28b68
#0  0x00002b06aa32e392 in ?? ()
(gdb) b ast_mutex_trylock
Function "ast_mutex_trylock" not defined.
Make breakpoint pending on future shared library load? (y or [n]) y

Breakpoint 1 (ast_mutex_trylock) pending.
(gdb) si 16000
The program is not being run.
(gdb) run
Starting program: /usr/sbin/asterisk
Cannot access memory at address 0x2b06a9b28b68
(gdb) si 160000

Program received signal SIGINT, Interrupt.
0x00002ab63def1639 in ?? ()
(gdb) si 16000
0x00002ab63deedbc7 in ?? ()
(gdb)