Codechange: Some more null checks

src/pathfinder/follow_track.hpp

@@ -124,8 +124,12 @@ struct CFollowTrackT
 		m_old_tile = old_tile;
 		m_old_td = old_td;
 		m_err = EC_NONE;
-		assert(((TrackStatusToTrackdirBits(GetTileTrackStatus(m_old_tile, TT(), IsRoadTT() ? RoadVehicle::From(m_veh)->compatible_roadtypes : 0)) & TrackdirToTrackdirBits(m_old_td)) != 0) ||
-		       (IsTram() && GetSingleTramBit(m_old_tile) != INVALID_DIAGDIR)); // Disable the assertion for single tram bits
+		assert(
+			((TrackStatusToTrackdirBits(
+				GetTileTrackStatus(m_old_tile, TT(), (IsRoadTT() && m_veh != NULL) ? RoadVehicle::From(m_veh)->compatible_roadtypes : 0)
+			) & TrackdirToTrackdirBits(m_old_td)) != 0) ||
+			(IsTram() && GetSingleTramBit(m_old_tile) != INVALID_DIAGDIR) // Disable the assertion for single tram bits
+		);
 		m_exitdir = TrackdirToExitdir(m_old_td);
 		if (ForcedReverse()) return true;
 		if (!CanExitOldTile()) return false;

src/train_cmd.cpp

@@ -874,7 +874,7 @@ static void RemoveFromConsist(Train *part, bool chain = false)
 static void InsertInConsist(Train *dst, Train *chain)
 {
 	/* We do not want to add something in the middle of an articulated part. */
-	assert(dst->Next() == NULL || !dst->Next()->IsArticulatedPart());
+	assert(dst != NULL && (dst->Next() == NULL || !dst->Next()->IsArticulatedPart()));
 
 	chain->Last()->SetNext(dst->Next());
 	dst->SetNext(chain);