[RP] Bug - 'windows' command kills RP

[Doug Kearns]

If defwinfmt contains a format character for which there is no
corresponding attribute defined, the windows command will kill
RP.

Program received signal SIGSEGV, Segmentation fault.
0x0805309b in sbuf_concat (b=0x8060b40, str=0x0) at sbuf.c:61
61        minsz = b->len + strlen (str) + 1;
(gdb) bt
#0  0x0805309b in sbuf_concat (b=0x8060b40, str=0x0) at sbuf.c:61
#1  0x08050ccd in format_window_name (fmt=0x805ae59 "a", win=0x80609f8, 
    other_win=0x0, buffer=0x8060b40) at list.c:694
#2  0x08050de1 in get_window_list (fmt=0x805ae58 "%a", delim=0x0, 
    buffer=0x8060b40, mark_start=0xbfffefa0, mark_end=0xbfffefa4) at
list.c:740
#3  0x0804d337 in update_window_names (s=0x8059140) at bar.c:116
#4  0x0804d24f in show_bar (s=0x8059140) at bar.c:69
#5  0x0804bb82 in cmd_windows (interactive=1, data=0x0) at
actions.c:1074
#6  0x0804b642 in command (interactive=1, data=0x805abf8 "windows")
    at actions.c:858
#7  0x0804e66b in handle_key (s=0x8059140) at events.c:419
#8  0x0804e725 in key_press (ev=0x8057b00) at events.c:457
#9  0x0804f839 in handle_events () at events.c:856
#10 0x08051a20 in main (argc=1, argv=0xbffff134) at main.c:510
#11 0x4012a237 in __libc_start_main () from /lib/libc.so.6
(gdb)

Regards,
Doug