1 files changed, 1 insertions, 1 deletions
diff --git a/src/pbs.h b/src/pbs.h
index a02d4d06e..96f9184b2 100644
--- a/src/pbs.h
+++ b/src/pbs.h
@@ -44,7 +44,7 @@ struct PBSTileInfo {
 	PBSTileInfo(TileIndex _t, Trackdir _td, bool _okay) : tile(_t), trackdir(_td), okay(_okay) {}
 };
 
-PBSTileInfo FollowTrainReservation(const Train *v, Vehicle **train_on_res = NULL);
+PBSTileInfo FollowTrainReservation(const Train *v, Vehicle **train_on_res = nullptr);
 bool IsSafeWaitingPosition(const Train *v, TileIndex tile, Trackdir trackdir, bool include_line_end, bool forbid_90deg = false);
 bool IsWaitingPositionFree(const Train *v, TileIndex tile, Trackdir trackdir, bool forbid_90deg = false);