diff --git a/include/extern.h b/include/extern.h
index 4e2314d..e7dfcd9 100644
--- a/include/extern.h
+++ b/include/extern.h
@@ -1676,7 +1676,7 @@ E NhRegion *FDECL(visible_region_at, (XCHAR_P,XCHAR_P));
 E void FDECL(show_region, (NhRegion*, XCHAR_P, XCHAR_P));
 E void FDECL(save_regions, (int,int));
 E void FDECL(rest_regions, (int,BOOLEAN_P));
-E NhRegion* FDECL(create_gas_cloud, (XCHAR_P, XCHAR_P, int, int));
+E NhRegion* FDECL(create_gas_cloud, (XCHAR_P, XCHAR_P, int, size_t));
 
 /* ### restore.c ### */
 
diff --git a/include/monst.h b/include/monst.h
index af2bb78..d04c318 100644
--- a/include/monst.h
+++ b/include/monst.h
@@ -40,7 +40,7 @@
 struct monst {
 	struct monst *nmon;
 	struct permonst *data;
-	unsigned m_id;
+	size_t m_id;
 	short mnum;		/* permanent monster index number */
 	short movement;		/* movement points (derived from permonst definition and added effects */
 	uchar m_lev;		/* adjusted difficulty level of monster */
diff --git a/include/obj.h b/include/obj.h
index 516fc35..1f569d9 100644
--- a/include/obj.h
+++ b/include/obj.h
@@ -22,7 +22,7 @@ struct obj {
 #define ocarry		v.v_ocarry
 
 	struct obj *cobj;	/* contents list for containers */
-	unsigned o_id;
+	size_t o_id;
 	xchar ox,oy;
 	short otyp;		/* object class number */
 	unsigned owt;
diff --git a/src/light.c b/src/light.c
index d0029e7..9fc6da5 100644
--- a/src/light.c
+++ b/src/light.c
@@ -308,10 +308,10 @@ relink_light_sources(ghostly)
 	if (ls->flags & LSF_NEEDS_FIXUP) {
 	    if (ls->type == LS_OBJECT || ls->type == LS_MONSTER) {
 		if (ghostly) {
-		    if (!lookup_id_mapping((unsigned)ls->id, &nid))
+		    if (!lookup_id_mapping((size_t)ls->id, &nid))
 			impossible("relink_light_sources: no id mapping");
 		} else
-		    nid = (unsigned) ls->id;
+		    nid = (size_t) ls->id;
 		if (ls->type == LS_OBJECT) {
 		    which = 'o';
 		    ls->id = (genericptr_t) find_oid(nid);
diff --git a/src/region.c b/src/region.c
index e4d12af..0bda6c0 100644
--- a/src/region.c
+++ b/src/region.c
@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)region.c	3.4	2002/10/15	*/
+/*	SCCS Id: @(#)region.c	5.4	2002/10/15	*/
 /* Copyright (c) 1996 by Jean-Christophe Collet	 */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -878,10 +878,10 @@ genericptr_t p1;
 genericptr_t p2;
 {
     NhRegion *reg;
-    int damage;
+    size_t damage;
 
     reg = (NhRegion *) p1;
-    damage = (int) reg->arg;
+    damage = (size_t) reg->arg;
 
     /* If it was a thick cloud, it dissipates a little first */
     if (damage >= 5) {
@@ -903,7 +903,7 @@ genericptr_t p2;
     int dam;
 
     reg = (NhRegion *) p1;
-    dam = (int) reg->arg;
+    dam = (size_t) reg->arg;
     if (p2 == NULL) {		/* This means *YOU* Bozo! */
 	if (nonliving(youmonst.data) || Breathless)
 	    return FALSE;
@@ -951,7 +951,7 @@ NhRegion *
 create_gas_cloud(x, y, radius, damage)
 xchar x, y;
 int radius;
-int damage;
+size_t damage;
 {
     NhRegion *cloud;
     int i, nrect;
diff --git a/src/timeout.c b/src/timeout.c
index 6a336d6..01ee21d 100644
--- a/src/timeout.c
+++ b/src/timeout.c
@@ -1836,10 +1836,10 @@ relink_timers(ghostly)
 	if (curr->needs_fixup) {
 	    if (curr->kind == TIMER_OBJECT) {
 		if (ghostly) {
-		    if (!lookup_id_mapping((unsigned)curr->arg, &nid))
+		    if (!lookup_id_mapping((size_t)curr->arg, &nid))
 			panic("relink_timers 1");
 		} else
-		    nid = (unsigned) curr->arg;
+		    nid = (size_t) curr->arg;
 		curr->arg = (genericptr_t) find_oid(nid);
 		if (!curr->arg) panic("cant find o_id %d", nid);
 		curr->needs_fixup = 0;