--- a/bot.c
+++ b/bot.c
@@ -104,7 +104,7 @@
 
 /* objects */
 struct object_list objects;
-struct object_list *last_obj;
+extern struct object_list *last_obj;
 struct it* hero;
 
 unsigned long_long game_start_offset; /* time difference between game start on this machine and on server */
--- a/client.c
+++ b/client.c
@@ -97,7 +97,7 @@
 
 /* objects */
 struct object_list objects;
-struct object_list *last_obj;
+extern struct object_list *last_obj;
 struct it* hero;
 
 /* important sprites */
--- a/data.c
+++ b/data.c
@@ -13,6 +13,9 @@
 #include "md5.h"
 #include "error.h"
 
+unsigned char *weapon_name[ARMS];
+struct obj_attr_type obj_attr[N_TYPES];
+struct weapon_type weapon[ARMS];
 
 #ifdef TRI_D
 int tri_d=0;
--- a/data.h
+++ b/data.h
@@ -62,7 +62,7 @@
 
 #define ARMS 5
 
-unsigned char *weapon_name[ARMS];
+extern unsigned char *weapon_name[ARMS];
 
 /* STATUS
 0: walk
@@ -91,7 +91,8 @@
 		      bit 1=server updates
 		      bit 2=server sends updates to clients
 		      */
-}obj_attr[N_TYPES];
+};
+extern struct obj_attr_type obj_attr[N_TYPES];
 
 
 /* weapon attribut table */
@@ -107,7 +108,8 @@
 	unsigned char add_ammo;
 	unsigned char max_ammo;
 	my_double shell_xspeed,shell_yspeed;
-}weapon[ARMS];
+};
+extern struct weapon_type weapon[ARMS];
 
 
 /* object in the game */
--- a/editor.c
+++ b/editor.c
@@ -26,7 +26,7 @@
 int oldx=0,oldy=0;  /* old cursor position */
 
 struct object_list objects;
-struct object_list *last_obj;
+extern struct object_list *last_obj;
 int level_number;
 
 
--- a/server.c
+++ b/server.c
@@ -100,7 +100,7 @@
 struct object_list objects;
 
 struct player_list *last_player;
-struct object_list *last_obj;
+extern struct object_list *last_obj;
 
 
 #ifdef WIN32