Codefix: Clear m8 when making tiles.

m8 should be cleared when tiles do not use it.

src/industry_map.h

@@ -287,6 +287,7 @@ inline void MakeIndustry(Tile t, IndustryID index, IndustryGfx gfx, uint8_t rand
 	SetWaterClass(t, wc);
 	SB(t.m6(), 6, 2, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 #endif /* INDUSTRY_MAP_H */

src/object_map.h

@@ -82,6 +82,7 @@ inline void MakeObject(Tile t, Owner o, ObjectID index, WaterClass wc, uint8_t r
 	t.m5() = index.base() >> 16;
 	SB(t.m6(), 2, 6, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 #endif /* OBJECT_MAP_H */

src/road_map.h

@@ -621,6 +621,7 @@ inline void MakeRoadNormal(Tile t, RoadBits bits, RoadType road_rt, RoadType tra
 	t.m5() = (road_rt != INVALID_ROADTYPE ? bits : 0) | ROAD_TILE_NORMAL << 6;
 	SB(t.m6(), 2, 6, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 	SetRoadTypes(t, road_rt, tram_rt);
 	SetRoadOwner(t, RTT_TRAM, tram);
 }

src/town_map.h

@@ -386,6 +386,7 @@ inline void MakeHouseTile(Tile t, TownID tid, uint8_t counter, uint8_t stage, Ho
 	SetHouseProtected(t, house_protected);
 	SetAnimationFrame(t, 0);
 	SetHouseProcessingTime(t, HouseSpec::Get(type)->processing_time);
+	SB(t.m8(), 12, 4, 0);
 }
 
 #endif /* TOWN_MAP_H */

src/tree_map.h

@@ -252,6 +252,7 @@ inline void MakeTree(Tile t, TreeType type, uint count, TreeGrowthStage growth,
 	t.m5() = count << 6 | static_cast<uint>(growth);
 	SB(t.m6(), 2, 6, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 #endif /* TREE_MAP_H */

src/void_map.h

@@ -27,6 +27,7 @@ inline void MakeVoid(Tile t)
 	t.m5() = 0;
 	t.m6() = 0;
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 #endif /* VOID_MAP_H */

src/water_map.h

@@ -393,6 +393,7 @@ inline void MakeShore(Tile t)
 	SetWaterTileType(t, WATER_TILE_COAST);
 	SB(t.m6(), 2, 6, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 /**
@@ -415,6 +416,7 @@ inline void MakeWater(Tile t, Owner o, WaterClass wc, uint8_t random_bits)
 	SetWaterTileType(t, WATER_TILE_CLEAR);
 	SB(t.m6(), 2, 6, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 /**
@@ -470,6 +472,7 @@ inline void MakeShipDepot(Tile t, Owner o, DepotID did, DepotPart part, Axis a,
 	SetWaterTileType(t, WATER_TILE_DEPOT);
 	SB(t.m6(), 2, 6, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 /**
@@ -494,6 +497,7 @@ inline void MakeLockTile(Tile t, Owner o, LockPart part, DiagDirection dir, Wate
 	SetWaterTileType(t, WATER_TILE_LOCK);
 	SB(t.m6(), 2, 6, 0);
 	t.m7() = 0;
+	t.m8() = 0;
 }
 
 /**