Merge branch 'master' into jgrpp

# Conflicts:
#	src/blitter/32bpp_anim.hpp
#	src/blitter/32bpp_base.hpp
#	src/blitter/8bpp_base.hpp
#	src/blitter/null.hpp
#	src/cheat_gui.cpp
#	src/gfx.cpp
#	src/linkgraph/linkgraph.cpp
#	src/spriteloader/grf.cpp
#	src/station_cmd.cpp

src/heightmap.cpp

@@ -188,7 +188,7 @@ static bool ReadHeightmapPNG(const char *filename, uint *x, uint *y, byte **map)
 	}
 
 	if (map != nullptr) {
-		*map = MallocT<byte>(width * height);
+		*map = MallocT<byte>(static_cast<size_t>(width) * height);
 		ReadHeightmapPNGImageData(*map, png_ptr, info_ptr);
 	}
 
@@ -303,7 +303,7 @@ static bool ReadHeightmapBMP(const char *filename, uint *x, uint *y, byte **map)
 			return false;
 		}
 
-		*map = MallocT<byte>(info.width * info.height);
+		*map = MallocT<byte>(static_cast<size_t>(info.width) * info.height);
 		ReadHeightmapBMPImageData(*map, &info, &data);
 	}