(gdb) bt full
#0  0x00007ff021afbbb9 in __GI_raise (sig=sig@entry=6) at ../nptl/sysdeps/unix/sysv/linux/raise.c:56
        resultvar = 0
        pid = 15340
        selftid = 24101
#1  0x00007ff021afefc8 in __GI_abort () at abort.c:89
        save_stage = 2
        act = {__sigaction_handler = {sa_handler = 0x0, sa_sigaction = 0x0}, sa_mask = {__val = {140669240336288, 9060866, 6152960, 20, 5428492, 1680, 6383266, 7, 140669240336360, 140669240336360, 140669240336312, 140669240336360,
              140669240336360, 140669240013168, 140669334270854, 1419719102}}, sa_flags = 500200, sa_restorer = 0x1900000002}
        sigs = {__val = {32, 0 <repeats 15 times>}}
#2  0x00007ff021b38e14 in __libc_message (do_abort=do_abort@entry=1, fmt=fmt@entry=0x7ff021c475a8 "*** Error in `%s': %s: 0x%s ***\n") at ../sysdeps/posix/libc_fatal.c:175
        ap = {{gp_offset = 40, fp_offset = 1, overflow_arg_area = 0x7fefad428c50, reg_save_area = 0x7fefad428be0}}
        fd = 2
        on_2 = <optimized out>
        list = <optimized out>
        nlist = <optimized out>
        cp = <optimized out>
        written = <optimized out>
#3  0x00007ff021b450ee in malloc_printerr (ptr=<optimized out>, str=0x7ff021c47720 "free(): invalid next size (normal)", action=1) at malloc.c:4996
        buf = "00007ff01c14fd10"
        cp = <optimized out>
#4  _int_free (av=<optimized out>, p=<optimized out>, have_lock=0) at malloc.c:3840
        size = <optimized out>
        fb = <optimized out>
        nextchunk = <optimized out>
        nextsize = <optimized out>
        nextinuse = <optimized out>
        prevsize = <optimized out>
        bck = <optimized out>
        fwd = <optimized out>
        errstr = <optimized out>
        locked = <optimized out>
#5  0x00000000005b8c4c in channel_blob_dtor (obj=0x7ff01c18cde8) at stasis_channels.c:289
        event = 0x7ff01c18cde8
#6  0x0000000000458fb2 in internal_ao2_ref (func=0x5efd33 <__FUNCTION__.9289> "__ao2_ref", line=513, file=0x5efaab "astobj2.c", delta=-1, user_data=0x7ff01c18cde8) at astobj2.c:442
        obj_mutex = <optimized out>
        obj_rwlock = <optimized out>
        current_value = <optimized out>
#7  __ao2_ref (delta=-1, user_data=0x7ff01c18cde8) at astobj2.c:513
No locals.
#8  __ao2_cleanup (obj=0x7ff01c18cde8) at astobj2.c:526
No locals.
#9  0x0000000000458fb2 in internal_ao2_ref (func=0x5efd33 <__FUNCTION__.9289> "__ao2_ref", line=513, file=0x5efaab "astobj2.c", delta=-1, user_data=0x7ff01c19e218) at astobj2.c:442
        obj_mutex = <optimized out>
        obj_rwlock = <optimized out>
        current_value = <optimized out>
#10 __ao2_ref (delta=-1, user_data=0x7ff01c19e218) at astobj2.c:513
No locals.
#11 __ao2_cleanup (obj=obj@entry=0x7ff01c19e218) at astobj2.c:526
No locals.
#12 0x00000000005b31c8 in dispatch_exec_async (local=<optimized out>) at stasis.c:692
        sub = 0x23f1fe8
        message = 0x7ff01c19e218
#13 0x00000000005c8e86 in ast_taskprocessor_execute (tps=tps@entry=0x23f2148) at taskprocessor.c:767
        local = {local_data = 0x23f1fe8, data = 0x7ff01c19e218}
        t = 0x7ff01c152c30
#14 0x00000000005cf6f0 in execute_tasks (data=0x23f2148) at threadpool.c:1157
        tps = 0x23f2148
#15 0x00000000005c8de4 in ast_taskprocessor_execute (tps=0x2a7a588) at taskprocessor.c:769
        local = {local_data = 0x7ff0140079c0, data = 0x7ff014007990}
        t = 0x7ff01c14c4b0
#16 0x00000000005cff10 in threadpool_execute (pool=0x2a6c978) at threadpool.c:351
No locals.
#17 worker_active (worker=0x7ff014007988) at threadpool.c:1075
No locals.
#18 worker_start (arg=arg@entry=0x7ff014007988) at threadpool.c:995
        worker = 0x7ff014007988
        __PRETTY_FUNCTION__ = "worker_start"
#19 0x00000000005d928a in dummy_start (data=<optimized out>) at utils.c:1232
        __cancel_buf = {__cancel_jmp_buf = {{__cancel_jmp_buf = {140669104461056, -5683337435018804030, 0, 0, 140667380734400, 140667380733696, 5692514967887430850, -5683338161457576766}, __mask_was_saved = 0}}, __pad = {
            0x7fefad428ef0, 0x0, 0x7ff021c2bae2 <__libc_thread_freeres+34>, 0x0}}
        __cancel_arg = 0x7fefad429700
        __not_first_call = <optimized out>
        ret = <optimized out>
        a = {start_routine = 0x5cfb90 <worker_start>, data = 0x7ff014007988, name = 0x7ff014009500 "worker_start         started at [ 1049] threadpool.c worker_thread_start()"}
#20 0x00007ff0225e4182 in start_thread (arg=0x7fefad429700) at pthread_create.c:312
        __res = <optimized out>
        pd = 0x7fefad429700
        now = <optimized out>
        unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140667380733696, -5683337435018804030, 0, 0, 140667380734400, 140667380733696, 5692514967874847938, 5674814851094693058}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x0, 0x0},
            data = {prev = 0x0, cleanup = 0x0, canceltype = 0}}}
        not_first_call = <optimized out>
        pagesize_m1 = <optimized out>
        sp = <optimized out>
        freesize = <optimized out>
        __PRETTY_FUNCTION__ = "start_thread"
#21 0x00007ff021bbfefd in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111
No locals.