diff --git a/src/pathfinder/yapf/yapf_costrail.hpp b/src/pathfinder/yapf/yapf_costrail.hpp
--- a/src/pathfinder/yapf/yapf_costrail.hpp
+++ b/src/pathfinder/yapf/yapf_costrail.hpp
@@ -259,7 +259,7 @@ public:
 		assert(v != NULL);
 		assert(v->type == VEH_TRAIN);
 		assert(v->tcache.cached_total_length != 0);
-		int missing_platform_length = (v->tcache.cached_total_length + TILE_SIZE - 1) / TILE_SIZE - platform_length;
+		int missing_platform_length = CeilDiv(v->tcache.cached_total_length, TILE_SIZE) - platform_length;
 		if (missing_platform_length < 0) {
 			/* apply penalty for longer platform than needed */
 			cost += Yapf().PfGetSettings().rail_longer_platform_penalty + Yapf().PfGetSettings().rail_longer_platform_per_tile_penalty * -missing_platform_length;