Identify unused, never read, and never written vars

src/overworld.c

@@ -408,9 +408,11 @@ static void Overworld_ResetStateAfterWhiteOut(void)
     FlagClear(FLAG_SYS_SAFARI_MODE);
     FlagClear(FLAG_SYS_USE_STRENGTH);
     FlagClear(FLAG_SYS_USE_FLASH);
-    if (VarGet(VAR_0x4039) == 1)
+    // If you were defeated by Kyogre/Groudon and the step counter has
+    // maxed out, end the unusual weather.
+    if (VarGet(VAR_SHOULD_END_UNUSUAL_WEATHER) == 1)
     {
-        VarSet(VAR_0x4039, 0);
+        VarSet(VAR_SHOULD_END_UNUSUAL_WEATHER, 0);
         VarSet(VAR_UNUSUAL_WEATHER_LOCATION, UNUSUAL_WEATHER_NONE);
     }
 }