fix #K3907 - reviving buried corpse

Burying an olog-hai corpse with a boulder resulted in a panic when
its time to revive occurred.  I was able to reproduce this once but
failed with "you feel less hassled" several times (using same save
file for multiple tests) so I'm not quite sure what was happening.

A buried corpse was allowed to revive if it was for a zombie.  This
fix extends that to auto-revivers (trolls and Riders).  The corpse
keeps its revive_mon timer rather than changing that to zombify_mon.

If/when revival of a buried troll or Rider happens while in view, it
will "claw itself out of the ground" like zombies do.

doc/fixes3-7-0.txt

@@ -1552,6 +1552,8 @@ anti-magic field's reduction of hero's maximum energy could result in current
 if hero was killed by a wand zapped by a monster, cause of death was reported
 	as "killed by a bolt of <damage type> imagined by <monster>"
 throttle the difficulty of the monsters in theme room "buried zombies"
+buried troll whose auto-revive timer expired might triger panic with
+        "revive default case 6"
 
 
 Fixes to 3.7.0-x Platform and/or Interface Problems Exposed Via git Repository
@@ -1790,7 +1792,7 @@ Qt: use idPressed signal instead of buttonPressed and mappedString instead
 	of mapped for recent Qt (pr #913 by chasonr)
 Qt+macOS: fix control key (fixed all except for ^V); handle ^V as a shortcut
 Qt+macOS: rename menu entry "nethack->Preferences..." for invoking nethack's
-	key 'O' command to "Game->Run-time options" and entry "Game->Qt settings"
+	'O' command to "Game->Run-time options" and entry "Game->Qt settings"
 	for making persistent Qt customizations to "nethack->Preferences..."
 Qt+macOS: prevent game->Quit-without-saving from being hijacked for the nethack
 	menu by renaming it game->_Quit-without-saving (macOS only)

src/do.c

@@ -2002,10 +2002,16 @@ revive_corpse(struct obj *corpse)
     char cname[BUFSZ];
     struct obj *container = (struct obj *) 0;
     int container_where = 0;
-    boolean is_zomb = (mons[corpse->corpsenm].mlet == S_ZOMBIE);
+    int montype;
+    boolean is_zomb;
     coordxy corpsex, corpsey;
 
     where = corpse->where;
+    montype = corpse->corpsenm;
+    /* treat buried auto-reviver (troll, Rider?) like a zombie
+       so that it can dig itself out of the ground if it revives */
+    is_zomb = (mons[montype].mlet == S_ZOMBIE
+               || (where == OBJ_BURIED && is_reviver(&mons[montype])));
     is_uwep = (corpse == uwep);
     chewed = (corpse->oeaten != 0);
     Strcpy(cname, corpse_xname(corpse,

src/zap.c

@@ -839,12 +839,18 @@ revive(struct obj *corpse, boolean by_hero)
     boolean one_of;
     mmflags_nht mmflags = NO_MINVENT | MM_NOWAIT | MM_NOMSG;
     int montype, cgend, container_nesting = 0;
-    boolean is_zomb = (mons[corpse->corpsenm].mlet == S_ZOMBIE);
+    boolean is_zomb;
 
     if (corpse->otyp != CORPSE) {
         impossible("Attempting to revive %s?", xname(corpse));
         return (struct monst *) 0;
     }
+    montype = corpse->corpsenm;
+    /* treat buried auto-reviver (troll, Rider?) like a zombie
+       so that it can dig itself out of the ground if it revives */
+    is_zomb = mons[montype].mlet == S_ZOMBIE
+              || (corpse->where == OBJ_BURIED && is_reviver(&mons[montype]));
+
     /* if this corpse is being eaten, stop doing that; this should be done
        after makemon() succeeds and skipped if it fails, but waiting until
        we know the result for that would be too late */
@@ -897,7 +903,6 @@ revive(struct obj *corpse, boolean by_hero)
         return (struct monst *) 0;
 
     /* prepare for the monster */
-    montype = corpse->corpsenm;
     mptr = &mons[montype];
     /* [should probably handle recorporealization first; if corpse and
        ghost are at same location, revived creature shouldn't be bumped