diff --git a/common/main/ai.h b/common/main/ai.h
index c7f61add6..ad84eb9b3 100644
--- a/common/main/ai.h
+++ b/common/main/ai.h
@@ -134,7 +134,7 @@ void create_path_to_player(vobjptridx_t objp, int max_length, int safety_flag);
 void attempt_to_resume_path(vobjptridx_t objp);
 
 // When a robot and a player collide, some robots attack!
-void do_ai_robot_hit_attack(vobjptridx_t robot, objptridx_t player, const vms_vector &collision_point);
+void do_ai_robot_hit_attack(vobjptridx_t robot, vobjptridx_t player, const vms_vector &collision_point);
 #if defined(DXX_BUILD_DESCENT_I) || defined(DXX_BUILD_DESCENT_II)
 #if defined(DXX_BUILD_DESCENT_I)
 typedef vobjptr_t _ai_door_is_openable_objptr;
diff --git a/similar/main/ai.cpp b/similar/main/ai.cpp
index 8811e7355..0a3bae02f 100644
--- a/similar/main/ai.cpp
+++ b/similar/main/ai.cpp
@@ -937,7 +937,7 @@ static void set_next_fire_time(const vobjptr_t objp, ai_local *ailp, robot_info
 // ----------------------------------------------------------------------------------
 //	When some robots collide with the player, they attack.
 //	If player is cloaked, then robot probably didn't actually collide, deal with that here.
-void do_ai_robot_hit_attack(const vobjptridx_t robot, const objptridx_t playerobj, const vms_vector &collision_point)
+void do_ai_robot_hit_attack(const vobjptridx_t robot, const vobjptridx_t playerobj, const vms_vector &collision_point)
 {
 	ai_local		*ailp = &robot->ctype.ai_info.ail;
 	robot_info *robptr = &Robot_info[get_robot_id(robot)];