diff --git a/src/newgrf.cpp b/src/newgrf.cpp
--- a/src/newgrf.cpp
+++ b/src/newgrf.cpp
@@ -4270,13 +4270,13 @@ static ChangeInfoResult RailTypeChangeIn
 				int n = buf->ReadByte();
 				for (int j = 0; j != n; j++) {
 					RailTypeLabel label = buf->ReadDWord();
-					RailType rt = GetRailTypeByLabel(BSWAP32(label), false);
-					if (rt != INVALID_RAILTYPE) {
+					RailType resolved_rt = GetRailTypeByLabel(BSWAP32(label), false);
+					if (resolved_rt != INVALID_RAILTYPE) {
 						switch (prop) {
-							case 0x0F: SetBit(rti->powered_railtypes, rt);               FALLTHROUGH; // Powered implies compatible.
-							case 0x0E: SetBit(rti->compatible_railtypes, rt);            break;
-							case 0x18: SetBit(rti->introduction_required_railtypes, rt); break;
-							case 0x19: SetBit(rti->introduces_railtypes, rt);            break;
+							case 0x0F: SetBit(rti->powered_railtypes, resolved_rt);               FALLTHROUGH; // Powered implies compatible.
+							case 0x0E: SetBit(rti->compatible_railtypes, resolved_rt);            break;
+							case 0x18: SetBit(rti->introduction_required_railtypes, resolved_rt); break;
+							case 0x19: SetBit(rti->introduces_railtypes, resolved_rt);            break;
 						}
 					}
 				}
@@ -4484,12 +4484,12 @@ static ChangeInfoResult RoadTypeChangeIn
 				int n = buf->ReadByte();
 				for (int j = 0; j != n; j++) {
 					RoadTypeLabel label = buf->ReadDWord();
-					RoadType rt = GetRoadTypeByLabel(BSWAP32(label), false);
-					if (rt != INVALID_ROADTYPE) {
+					RoadType resolved_rt = GetRoadTypeByLabel(BSWAP32(label), false);
+					if (resolved_rt != INVALID_ROADTYPE) {
 						switch (prop) {
-							case 0x0F: SetBit(rti->powered_roadtypes, rt);               break;
-							case 0x18: SetBit(rti->introduction_required_roadtypes, rt); break;
-							case 0x19: SetBit(rti->introduces_roadtypes, rt);            break;
+							case 0x0F: SetBit(rti->powered_roadtypes, resolved_rt);               break;
+							case 0x18: SetBit(rti->introduction_required_roadtypes, resolved_rt); break;
+							case 0x19: SetBit(rti->introduces_roadtypes, resolved_rt);            break;
 						}
 					}
 				}