From 5e2236a3ef27555e9d86384909c2bf49dbf08e7f Mon Sep 17 00:00:00 2001
From: Pasi Kallinen <paxed@alt.org>
Date: Thu, 10 Jan 2019 21:47:04 +0200
Subject: [PATCH] Fix accessing deleted fire trap

melt_ice can delete the fire trap, in the case where the trap
is on ice, and a monster carrying a boulder triggers it, then drowns.

mintrap -> minliquid -> mondead -> ... -> mdrop_obj ->
   flooreffects -> boulder_hits_pool -> delfloortrap
---
 src/trap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/trap.c b/src/trap.c
index 965c9347e..50f74b79c 100644
--- a/src/trap.c
+++ b/src/trap.c
@@ -2421,7 +2421,7 @@ register struct monst *mtmp;
                 You("smell smoke.");
             if (is_ice(mtmp->mx, mtmp->my))
                 melt_ice(mtmp->mx, mtmp->my, (char *) 0);
-            if (see_it)
+            if (see_it && t_at(mtmp->mx, mtmp->my))
                 seetrap(trap);
             break;
         case PIT: