Codechange: Initialise a few variables that -flto seems to think could possibly be uninitialised

src/order_base.h

@@ -50,7 +50,7 @@ private:
 public:
 	Order *next;          ///< Pointer to next order. If NULL, end of list
 
-	Order() : refit_cargo(CT_NO_REFIT), max_speed(UINT16_MAX) {}
+	Order() : flags(0), refit_cargo(CT_NO_REFIT), max_speed(UINT16_MAX) {}
 	~Order();
 
 	Order(uint32 packed);

src/strings.cpp

@@ -118,7 +118,8 @@ void SetDParamMaxValue(uint n, uint64 max_value, uint min_count, FontSize size)
  */
 void SetDParamMaxDigits(uint n, uint count, FontSize size)
 {
-	uint front, next;
+	uint front = 0;
+	uint next = 0;
 	GetBroadestDigit(&front, &next, size);
 	uint64 val = count > 1 ? front : next;
 	for (; count > 1; count--) {

src/vehicle_cmd.cpp

@@ -131,7 +131,7 @@ CommandCost CmdBuildVehicle(TileIndex tile, DoCommandFlag flags, uint32 p1, uint
 	DoCommandFlag subflags = flags;
 	if (refitting) subflags |= DC_EXEC;
 
-	Vehicle *v;
+	Vehicle *v = NULL;
 	switch (type) {
 		case VEH_TRAIN:    value.AddCost(CmdBuildRailVehicle(tile, subflags, e, GB(p1, 24, 8), &v)); break;
 		case VEH_ROAD:     value.AddCost(CmdBuildRoadVehicle(tile, subflags, e, GB(p1, 24, 8), &v)); break;