(gdb) bt
#0  __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
#1  0x00007fc412a9980f in _L_lock_12013 () from /lib/x86_64-linux-gnu/libc.so.6
#2  0x00007fc412a978d8 in __libc_free (mem=0x7fc412daa1c0) at malloc.c:3736
#3  0x00000000004a3a12 in _XSERVTransFreeConnInfo (ciptr=0x10faf60) at /usr/include/X11/Xtrans/Xtrans.c:138
#4  0x00000000004a3ef4 in _XSERVTransClose (ciptr=0x10faf60) at /usr/include/X11/Xtrans/Xtrans.c:930
#5  0x0000000000461f1f in CloseWellKnownConnections () at ../../os/connection.c:493
#6  0x000000000045e598 in SigAbortServer (signo=11) at ../../os/log.c:409
#7  0x000000000045f1d2 in FatalSignal (signo=11) at ../../os/log.c:541
#8  <signal handler called>
#9  _int_malloc (av=0x7fc412daa1c0, bytes=<value optimized out>) at malloc.c:4709
#10 0x00007fc412a96112 in _int_realloc (av=0x7fc412daa1c0, oldp=0x271abf0, oldsize=<value optimized out>, nb=261696)
    at malloc.c:5290
#11 0x00007fc412a97b19 in __libc_realloc (oldmem=0x271ac00, bytes=261684) at malloc.c:3821
#12 0x0000000000466061 in ReadRequestFromClient (client=0x14fd960) at ../../os/io.c:325
#13 0x00000000004280c1 in Dispatch () at ../../dix/dispatch.c:412
#14 0x0000000000421a7e in main (argc=8, argv=<value optimized out>, envp=<value optimized out>) at ../../dix/main.c:287
(gdb) bt full
#0  __lll_lock_wait_private () at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:97
No locals.
#1  0x00007fc412a9980f in _L_lock_12013 () from /lib/x86_64-linux-gnu/libc.so.6
No symbol table info available.
#2  0x00007fc412a978d8 in __libc_free (mem=0x7fc412daa1c0) at malloc.c:3736
        ar_ptr = 0x7fc412daa1c0
        p = 0x10fafb0
        hook = <value optimized out>
#3  0x00000000004a3a12 in _XSERVTransFreeConnInfo (ciptr=0x10faf60) at /usr/include/X11/Xtrans/Xtrans.c:138
No locals.
#4  0x00000000004a3ef4 in _XSERVTransClose (ciptr=0x10faf60) at /usr/include/X11/Xtrans/Xtrans.c:930
        ret = 0
#5  0x0000000000461f1f in CloseWellKnownConnections () at ../../os/connection.c:493
        i = <value optimized out>
#6  0x000000000045e598 in SigAbortServer (signo=11) at ../../os/log.c:409
No locals.
#7  0x000000000045f1d2 in FatalSignal (signo=11) at ../../os/log.c:541
        beenhere = 1
#8  <signal handler called>
No symbol table info available.
#9  _int_malloc (av=0x7fc412daa1c0, bytes=<value optimized out>) at malloc.c:4709
        p = <value optimized out>
        iters = <value optimized out>
        nb = 261696
        idx = 125
        bin = 0x7fc412daa9d8
        victim = 0x2ecd820
        size = <value optimized out>
        victim_index = <value optimized out>
        remainder = 0x2f0d660
        remainder_size = <value optimized out>
        block = <value optimized out>
        bit = <value optimized out>
        map = 57147392
---Type <return> to continue, or q <return> to quit---
        fwd = <value optimized out>
        bck = <value optimized out>
        errstr = 0x0
        __func__ = "_int_malloc"
#10 0x00007fc412a96112 in _int_realloc (av=0x7fc412daa1c0, oldp=0x271abf0, oldsize=<value optimized out>, nb=261696)
    at malloc.c:5290
        nextsize = <value optimized out>
        newp = <value optimized out>
        newsize = <value optimized out>
        newmem = <value optimized out>
        next = 0x271bc00
        remainder = <value optimized out>
        remainder_size = <value optimized out>
        bck = <value optimized out>
        fwd = <value optimized out>
        copysize = <value optimized out>
        ncopies = <value optimized out>
        s = <value optimized out>
        errstr = 0x0
        __func__ = "_int_realloc"
#11 0x00007fc412a97b19 in __libc_realloc (oldmem=0x271ac00, bytes=261684) at malloc.c:3821
        ar_ptr = 0x7fc412daa1c0
        nb = 261696
        newp = <value optimized out>
        hook = <value optimized out>
        oldp = 0x271abf0
        oldsize = 4112
        __func__ = "__libc_realloc"
#12 0x0000000000466061 in ReadRequestFromClient (client=0x14fd960) at ../../os/io.c:325
        ibuf = <value optimized out>
        oc = <value optimized out>
        oci = 0x14ad170
        fd = 49
        gotnow = 3932
---Type <return> to continue, or q <return> to quit---
        needed = <value optimized out>
        result = <value optimized out>
        request = <value optimized out>
        need_header = <value optimized out>
        move_header = <value optimized out>
        __PRETTY_FUNCTION__ = "ReadRequestFromClient"
#13 0x00000000004280c1 in Dispatch () at ../../dix/dispatch.c:412
        clientReady = 0x1390620
        result = <value optimized out>
        client = 0x14fd960
        nready = -1
        icheck = 0x7f1290
        start_tick = 1140
#14 0x0000000000421a7e in main (argc=8, argv=<value optimized out>, envp=<value optimized out>) at ../../dix/main.c:287
        i = <value optimized out>
        alwaysCheckForInput = {0, 1}