I installed cups-dbg and got this backtrace on the core file:
(gdb) thread apply all bt full

Thread 1 (process 10495):
#0  0x00007f7b20a70f85 in raise () from /lib/libc.so.6
No symbol table info available.
#1  0x00007f7b20a72af3 in abort () from /lib/libc.so.6
No symbol table info available.
#2  0x00007f7b20a69ed9 in __assert_fail () from /lib/libc.so.6
No symbol table info available.
#3  0x00007f7b20b0e0ff in rfc3484_sort () from /lib/libc.so.6
No symbol table info available.
#4  0x00007f7b20a736e8 in msort_with_tmp () from /lib/libc.so.6
No symbol table info available.
#5  0x00007f7b20a73c4f in qsort_r () from /lib/libc.so.6
No symbol table info available.
#6  0x00007f7b20b0d41a in getaddrinfo () from /lib/libc.so.6
No symbol table info available.
#7  0x00007f7b214ac226 in httpAddrGetList (hostname=0x7f7b22f83f50 "fox.dooz.org", family=0, service=0x0) at http-addrlist.c:302
        current = <value optimized out>
        hints = {ai_flags = 0, ai_family = 0, ai_socktype = 1, ai_protocol = 0, ai_addrlen = 0, ai_addr = 0x0, ai_canonname = 0x0, ai_next = 0x0}
        results = <value optimized out>
        ipv6 = "C^�\000\000\000\000�&\000\000\000\000\000x\000\000\000\000\000\000\000�\030\212*�\177\000\000x\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000� {\177\000\000zfc\"{\177\000\000\001\000\000\000{\177\000\000\000\000\000\000\000\000\000\000Ag? {\177\000\000\000\020�\000\000``:�>� {\177\000\000\000\000\000\000\000\000\000\000\027\031\212*�\177\000\000\000\000\000\000\000\000\000\000\003", '\0' <repeats 15 times>, "\004\000\000\000\000\000\000\000`\234< {\177\000\000\004\000\000\000\000\000\000\000x\000\000\000\000\000\000\000\220\030\212*�\177\000\000x\000\000\000\000\000\000\000�\030\212*�\177\000\000%�> {"...
        ipv6len = 0
        error = <value optimized out>
        first = <value optimized out>
        addr = <value optimized out>
        cg = (_cups_globals_t *) 0x7f7b22f84f70
#8  0x00007f7b2287ec40 in cupsdStartListening () at listen.c:152
        status = <value optimized out>
        p = <value optimized out>
        val = <value optimized out>
        lis = <value optimized out>
        s = '\0' <repeats 73 times>, "\020�\000\000``:", '\0' <repeats 16 times>, "\001\000\000\000\000\000\000\000����������������*\227< {\177\000\000\001\000\000\000\000\000\000\000\211�< {\177\000\000�� {\177\000\0000\034\212*�\177\000\000\000\000\000\000\000\000\000\000\001\000\000\000\000\000\000\000\227\034\212*�\177\000\000\000\000\000\000\000\000\000\000�(\000\000�(\000\000\000\000\000\000\000\000\000\000Hyb\"{\177\000\000 \035\212*�\177\000\000ܠ\211\"{\177\000\000\002\000\000\000\000\000\000\000\001\000\000\000\000\000\000\000έ<\"{\177\000"
        have_domain = <value optimized out>
        encryptions = {0x7f7b2289dc31 "IfRequested", 0x7f7b2289dc3d "Never", 0x7f7b228949e6 "Required", 0x7f7b2289dc43 "Always"}
#9  0x00007f7b2288dffb in cupsdStartServer () at server.c:86
No locals.
#10 0x00007f7b2286d29c in main (argc=2, argv=<value optimized out>) at main.c:538
        i = 2
        opt = <value optimized out>
        fg = 1
        fds = <value optimized out>
        con = <value optimized out>
        job = <value optimized out>
        lis = <value optimized out>
        current_time = <value optimized out>
        browse_time = <value optimized out>
        senddoc_time = <value optimized out>
        expire_time = <value optimized out>
        report_time = <value optimized out>
        event_time = <value optimized out>
        timeout = <value optimized out>
        limit = {rlim_cur = 1024, rlim_max = 1024}
        action = {__sigaction_handler = {sa_handler = 0x7fff2a8a1bd0, sa_sigaction = 0x7fff2a8a1bd0}, sa_mask = {__val = {0, 140166836840841, 140166834638503, 140166257704961, 140166836664744, 140733907082512, 0, 140166836840685, 140166834638503, 140166257704961, 
      140166834625452, 140733907082560, 140166836634824, 12, 31, 2090266759}}, sa_flags = 576921696, sa_restorer = 0x7f7b20a41b30}
        netif_time = <value optimized out>