* @param mode オプション
* @return 踏破可能ならばTRUEを返す
*/
-bool monster_can_cross_terrain(PlayerType *player_ptr, FEAT_IDX feat, MonsterRaceInfo *r_ptr, BIT_FLAGS16 mode)
+bool monster_can_cross_terrain(PlayerType *player_ptr, FEAT_IDX feat, const MonsterRaceInfo *r_ptr, BIT_FLAGS16 mode)
{
auto *f_ptr = &terrains_info[feat];