[Freeciv-Dev] (PR#14346) Vision crash

["Per I. Mathisen" <per@xxxxxxxxxxx>]

<URL: http://bugs.freeciv.org/Ticket/Display.html?id=14346 >

To reproduce: Start server, connect client, play a few turns, disconnect
client, quit game.

2: Lost connection: perrin from localhost (player Hrolf Gangr).
> q
Goodbye.
civserver: maphand.c:1760: vision_free: Assertion `server_state !=
RUN_GAME_STATE || vision->radius_sq < 0' failed.

Program received signal SIGABRT, Aborted.
[Switching to Thread -1208403200 (LWP 6477)]
0x0019b402 in __kernel_vsyscall ()
(gdb) bt
#0  0x0019b402 in __kernel_vsyscall ()
#1  0x00b73118 in raise () from /lib/libc.so.6
#2  0x00b74888 in abort () from /lib/libc.so.6
#3  0x00b6c2f5 in __assert_fail () from /lib/libc.so.6
#4  0x0807fefd in vision_free (vision=0x91173f0) at maphand.c:1760
#5  0x080523d6 in server_game_free () at srv_main.c:1908
#6  0x08050581 in server_quit () at srv_main.c:821
#7  0x0805a1bc in quit_game (caller=0x0, check=false) at stdinhand.c:3353
#8  0x0805ab96 in handle_stdin_input (caller=0x0, str=0x915db10 "q",
check=false)
    at stdinhand.c:3538
#9  0x080a044c in handle_readline_input_callback (line=0x915b608 "q") at
sernet.c:178
#10 0x00cd582c in rl_callback_read_char () from /usr/lib/libreadline.so.5
#11 0x080a1573 in sniff_packets () at sernet.c:652
#12 0x08051a96 in main_loop () at srv_main.c:1583
#13 0x08052351 in srv_loop () at srv_main.c:1884
#14 0x08051c96 in srv_main () at srv_main.c:1684
#15 0x0804af91 in main (argc=1, argv=0xbfaaa054) at civserver.c:242