Use FALSE instead of 0

src/item_use.c

@@ -221,7 +221,7 @@ static bool8 sub_80A1194(void)
     ScriptContext2_Enable();
     FadeInFromBlack();
     CreateTask(sub_80A11C0, 10);
-    gExitStairsMovementDisabled = 0;
+    gExitStairsMovementDisabled = FALSE;
     return TRUE;
 }
 

src/main_menu.c

@@ -468,7 +468,7 @@ static void Task_ExecuteMainMenuSelection(u8 taskId)
         {
         default:
         case MAIN_MENU_NEWGAME:
-            gExitStairsMovementDisabled = 0;
+            gExitStairsMovementDisabled = FALSE;
             FreeAllWindowBuffers();
             DestroyTask(taskId);
             StartNewGameScene();
@@ -476,7 +476,7 @@ static void Task_ExecuteMainMenuSelection(u8 taskId)
         case MAIN_MENU_CONTINUE:
             gPlttBufferUnfaded[0] = RGB_BLACK;
             gPlttBufferFaded[0] = RGB_BLACK;
-            gExitStairsMovementDisabled = 0;
+            gExitStairsMovementDisabled = FALSE;
             FreeAllWindowBuffers();
             TrySetUpQuestLogScenes_ElseContinueFromSave(taskId);
             break;