Frequent SIGSEGV's

[Jim Kingdon <kingdon at panix dot com>]

Yeah, I updated from CVS and I've been getting SIGSEGV's too.  It
seems to have something to do with pressing several keys in rapid
succession (well, at least that's what I was doing both times)...

In the enclosed code the fault is line 3978 and the variable "uimg" is NULL.

3975            if (emblem_position(uimg, ename, eimf, sw, sh, &ex,
&ey, &ew, &eh)) {
3976                    /* Make sure emblem stays within the cell when
drawing a single big icon
3977                    (should fix emblem_position instead of doing
this in the interfaces). */
3978                    if (uimg->h > mapw->vp->uh) {
3979                            sy += (mapw->vp->hh - mapw->vp->uh) /
2;
3980                            /* Tweaked by hand. */

Here's a stack trace:

#0  0x08064c83 in draw_unit_image (mapw=0x89637d0, sx=0, sy=135856696,
 sw=7,
    sh=4, u=1, s2=1, mod=0) at tkmap.c:3978
#1  0x08062d84 in draw_current (mapw=0x89637d0) at tkmap.c:3259
#2  0x0805af45 in draw_map_widget (mapw=0x89637d0) at tkmap.c:1066
#3  0x0805a5a1 in mapw_display (cldata=0x89637d0) at tkmap.c:782
#4  0x4007b319 in TclServiceIdle () from /usr/lib/libtcl.so.0
#5  0x4006d672 in Tcl_DoOneEvent () from /usr/lib/libtcl.so.0
#6  0x400bd19d in Tk_UpdateObjCmd () from /usr/lib/libtk.so.0
#7  0x4006f5b1 in EvalObjv () from /usr/lib/libtcl.so.0
#8  0x4006fe10 in Tcl_EvalEx () from /usr/lib/libtcl.so.0
#9  0x40070185 in Tcl_Eval () from /usr/lib/libtcl.so.0
#10 0x40039813 in Tcl_GlobalEval () from /usr/lib/libtcl.so.0
#11 0x08052353 in eval_tcl_cmd (
    fmt=0x89637d0 " 6\226\b8\002\031\b
 (J\030\b\0209\226\b`.\226\b\200A\226\b\bA\226\b\001") at
 tkmain.c:3486
#12 0x08066ab1 in update_cell (map=0x8920ca8, x=8, y=39) at
 tkmap.c:4832
#13 0x0804e479 in update_cell_display (side=0x834c7d8, x=8, y=39,
 flags=3)
    at tkmain.c:1864
#14 0x080d4be8 in see_cell (side=0x834c7d8, x=8, y=39) at side.c:2759
#15 0x080d3684 in cover_area_1 (side=0x834c7d8, unit=0x818106c, x0=10,
 y0=37,
    nx=9, ny=38) at side.c:2274
#16 0x080d25be in cover_area (side=0x834c7d8, unit=0x818106c,
    oldtransport=0x0, x0=10, y0=37, nx=9, ny=38) at side.c:2041)
#17 0x080d9a70 in change_cell_aux (unit=0x818106c, x0=10, y0=37, x=9,
 y=38)
    at unit.c:1120
#18 0x080d98f0 in change_cell (unit=0x818106c, x=9, y=38) at
 unit.c:1081
#19 0x08086c89 in move_unit (unit=0x818106c, nx=9, ny=38) at
 move.c:548
#20 0x08085b55 in do_move_action (unit=0x818106c, unit2=0x818106c,
 x=9, y=38,
    z=0) at move.c:197
#21 0x080842ab in execute_action (unit=0x818106c, action=0x896aea8)
    at actions.c:3433
#22 0x08092a61 in move_one_unit_multiple (unit=0x818106c, lim=1) at
 run.c:970
#23 0x080922b4 in side_move_some_units (side=0x834c7d8, lim=1) at
 run.c:811
#24 0x08091fd6 in move_some_units (lim=1) at run.c:731
#25 0x080915d7 in run_game (maxactions=1) at run.c:301
#26 0x080fe572 in net_run_game (maxactions=1) at tp.c:672
#27 0x0804cb6a in tk_run_game (cldata=0x0, interp=0x1, argc=1,
 argv=0x1)
    at tkmain.c:1236
#28 0x400376bb in TclInvokeStringCommand () from /usr/lib/libtcl.so.0
#29 0x400523dd in TclExecuteByteCode () from /usr/lib/libtcl.so.0
#30 0x40038002 in Tcl_EvalObjEx () from /usr/lib/libtcl.so.0
#31 0x4007640d in TclObjInterpProc () from /usr/lib/libtcl.so.0
#32 0x4006f5b1 in EvalObjv () from /usr/lib/libtcl.so.0
#33 0x4006fe10 in Tcl_EvalEx () from /usr/lib/libtcl.so.0
#34 0x4007bacb in AfterProc () from /usr/lib/libtcl.so.0
#35 0x4007b190 in TimerHandlerEventProc () from /usr/lib/libtcl.so.0
#36 0x4006d355 in Tcl_ServiceEvent () from /usr/lib/libtcl.so.0
#37 0x4006d637 in Tcl_DoOneEvent () from /usr/lib/libtcl.so.0
#38 0x0804e28b in ui_mainloop () at tkmain.c:1784
#39 0x0804ac53 in main (argc=1, argv=0x0) at xconq.c:126
#40 0x420158f7 in __libc_start_main () from /lib/i686/libc.so.6