diff --git a/src/newgrf_commons.cpp b/src/newgrf_commons.cpp
index 4fa37000a7..7dd5e22cbc 100644
--- a/src/newgrf_commons.cpp
+++ b/src/newgrf_commons.cpp
@@ -44,21 +44,10 @@ OverrideManagerBase::OverrideManagerBase(uint16 offset, uint16 maximum, uint16 i
 	max_new_entities = maximum;
 	invalid_ID = invalid;
 
-	mapping_ID = CallocT<EntityIDMapping>(max_new_entities);
-	entity_overrides = MallocT<uint16>(max_offset);
-	for (size_t i = 0; i < max_offset; i++) entity_overrides[i] = invalid;
-	grfid_overrides = CallocT<uint32>(max_offset);
-}
-
-/**
- * Destructor of the generic class.
- * Frees allocated memory of constructor
- */
-OverrideManagerBase::~OverrideManagerBase()
-{
-	free(mapping_ID);
-	free(entity_overrides);
-	free(grfid_overrides);
+	this->mapping_ID.resize(this->max_new_entities);
+	this->entity_overrides.resize(this->max_offset);
+	std::fill(this->entity_overrides.begin(), this->entity_overrides.end(), this->invalid_ID);
+	this->grfid_overrides.resize(this->max_offset);
 }
 
 /**
@@ -81,16 +70,14 @@ void OverrideManagerBase::Add(uint8 local_id, uint32 grfid, uint entity_type)
 /** Resets the mapping, which is used while initializing game */
 void OverrideManagerBase::ResetMapping()
 {
-	memset(mapping_ID, 0, (max_new_entities - 1) * sizeof(EntityIDMapping));
+	std::fill(this->mapping_ID.begin(), this->mapping_ID.end(), EntityIDMapping{});
 }
 
 /** Resets the override, which is used while initializing game */
 void OverrideManagerBase::ResetOverride()
 {
-	for (uint16 i = 0; i < max_offset; i++) {
-		entity_overrides[i] = invalid_ID;
-		grfid_overrides[i] = 0;
-	}
+	std::fill(this->entity_overrides.begin(), this->entity_overrides.end(), this->invalid_ID);
+	std::fill(this->grfid_overrides.begin(), this->grfid_overrides.end(), uint32());
 }
 
 /**
diff --git a/src/newgrf_commons.h b/src/newgrf_commons.h
index ff241369a2..6a908417b1 100644
--- a/src/newgrf_commons.h
+++ b/src/newgrf_commons.h
@@ -191,8 +191,8 @@ struct EntityIDMapping {
 
 class OverrideManagerBase {
 protected:
-	uint16 *entity_overrides;
-	uint32 *grfid_overrides;
+	std::vector<uint16> entity_overrides;
+	std::vector<uint32> grfid_overrides;
 
 	uint16 max_offset;       ///< what is the length of the original entity's array of specs
 	uint16 max_new_entities; ///< what is the amount of entities, old and new summed
@@ -201,10 +201,10 @@ protected:
 	virtual bool CheckValidNewID(uint16 testid) { return true; }
 
 public:
-	EntityIDMapping *mapping_ID; ///< mapping of ids from grf files.  Public out of convenience
+	std::vector<EntityIDMapping> mapping_ID; ///< mapping of ids from grf files.  Public out of convenience
 
 	OverrideManagerBase(uint16 offset, uint16 maximum, uint16 invalid);
-	virtual ~OverrideManagerBase();
+	virtual ~OverrideManagerBase() {}
 
 	void ResetOverride();
 	void ResetMapping();
@@ -267,7 +267,7 @@ public:
 struct AirportTileSpec;
 class AirportTileOverrideManager : public OverrideManagerBase {
 protected:
-	virtual bool CheckValidNewID(uint16 testid) { return testid != 0xFF; }
+	virtual bool CheckValidNewID(uint16 testid) override { return testid != 0xFF; }
 public:
 	AirportTileOverrideManager(uint16 offset, uint16 maximum, uint16 invalid) :
 			OverrideManagerBase(offset, maximum, invalid) {}
@@ -278,7 +278,7 @@ public:
 struct ObjectSpec;
 class ObjectOverrideManager : public OverrideManagerBase {
 protected:
-	virtual bool CheckValidNewID(uint16 testid) { return testid != 0xFF; }
+	virtual bool CheckValidNewID(uint16 testid) override { return testid != 0xFF; }
 public:
 	ObjectOverrideManager(uint16 offset, uint16 maximum, uint16 invalid) :
 			OverrideManagerBase(offset, maximum, invalid) {}