#0  0x0080e2bb in strlen () from /lib/tls/libc.so.6
(gdb) bt full
#0  0x0080e2bb in strlen () from /lib/tls/libc.so.6
No symbol table info available.
#1  0x007e2225 in vfprintf () from /lib/tls/libc.so.6
No symbol table info available.
#2  0x007fa41b in vsprintf () from /lib/tls/libc.so.6
No symbol table info available.
#3  0x007e765b in sprintf () from /lib/tls/libc.so.6
No symbol table info available.
#4  0x0076ff9e in function_fieldqty (chan=0x95d9030, cmd=0x143de20 "FIELDQTY", parse=0x143de29 "HASHKEYS(access_control)", 
    buf=0x752c6469 <Address 0x752c6469 out of bounds>, len=1965843561) at func_strings.c:60
        varname = Variable "varname" is not available.
(gdb) bt
#0  0x0080e2bb in strlen () from /lib/tls/libc.so.6
#1  0x007e2225 in vfprintf () from /lib/tls/libc.so.6
#2  0x007fa41b in vsprintf () from /lib/tls/libc.so.6
#3  0x007e765b in sprintf () from /lib/tls/libc.so.6
#4  0x0076ff9e in function_fieldqty (chan=0x95d9030, cmd=0x143de20 "FIELDQTY", parse=0x143de29 "HASHKEYS(access_control)", 
    buf=0x752c6469 <Address 0x752c6469 out of bounds>, len=1965843561) at func_strings.c:60
#5  0x080bcf14 in ast_func_read (chan=0x752c6469, function=0x143de20 "FIELDQTY", workspace=0x752c6469 <Address 0x752c6469 out of bounds>, len=1965843561)
    at pbx.c:1501
#6  0x080c2906 in pbx_substitute_variables_helper_full (c=0x95d9030, headp=0x95d9374, cp1=0x956de40 "NUM_FIELDS=${FIELDQTY(HASHKEYS(access_control)|,)}", 
    cp2=0x144303b "", count=8180) at pbx.c:1619
#7  0x080c64dc in pbx_extension_helper (c=0x95d9030, con=Variable "con" is not available.
) at pbx.c:1701
#8  0x080c78ef in __ast_pbx_run (c=0x95d9030) at pbx.c:2248
#9  0x080c979e in pbx_thread (data=0x95d9030) at pbx.c:2561
#10 0x080f5615 in dummy_start (data=0x0) at utils.c:545
#11 0x00332371 in start_thread () from /lib/tls/libpthread.so.0
#12 0x0086cffe in clone () from /lib/tls/libc.so.6