diff --git a/src/newgrf_config.cpp b/src/newgrf_config.cpp
--- a/src/newgrf_config.cpp
+++ b/src/newgrf_config.cpp
@@ -83,7 +83,7 @@ GRFConfig::GRFConfig(const GRFConfig &co
 	this->info->AddRef();
 	this->url->AddRef();
 	if (config.error != NULL) this->error = new GRFError(*config.error);
-	for (uint i = 0; i < config.param_info.Length(); i++) {
+	for (uint i = 0; i < config.param_info.size(); i++) {
 		if (config.param_info[i] == NULL) {
 			*this->param_info.Append() = NULL;
 		} else {
@@ -104,7 +104,7 @@ GRFConfig::~GRFConfig()
 	this->info->Release();
 	this->url->Release();
 
-	for (uint i = 0; i < this->param_info.Length(); i++) delete this->param_info[i];
+	for (uint i = 0; i < this->param_info.size(); i++) delete this->param_info[i];
 }
 
 /**
@@ -155,7 +155,7 @@ void GRFConfig::SetParameterDefaults()
 
 	if (!this->has_param_defaults) return;
 
-	for (uint i = 0; i < this->param_info.Length(); i++) {
+	for (uint i = 0; i < this->param_info.size(); i++) {
 		if (this->param_info[i] == NULL) continue;
 		this->param_info[i]->SetValue(this, this->param_info[i]->def_value);
 	}
@@ -261,7 +261,7 @@ GRFParameterInfo::GRFParameterInfo(GRFPa
 	num_bit(info.num_bit),
 	complete_labels(info.complete_labels)
 {
-	for (uint i = 0; i < info.value_names.Length(); i++) {
+	for (uint i = 0; i < info.value_names.size(); i++) {
 		SmallPair<uint32, GRFText *> *data = info.value_names.Get(i);
 		this->value_names.Insert(data->first, DuplicateGRFText(data->second));
 	}
@@ -272,7 +272,7 @@ GRFParameterInfo::~GRFParameterInfo()
 {
 	CleanUpGRFText(this->name);
 	CleanUpGRFText(this->desc);
-	for (uint i = 0; i < this->value_names.Length(); i++) {
+	for (uint i = 0; i < this->value_names.size(); i++) {
 		SmallPair<uint32, GRFText *> *data = this->value_names.Get(i);
 		CleanUpGRFText(data->second);
 	}
@@ -609,7 +609,7 @@ compatible_grf:
 				c->min_loadable_version = f->min_loadable_version;
 				c->num_valid_params = f->num_valid_params;
 				c->has_param_defaults = f->has_param_defaults;
-				for (uint i = 0; i < f->param_info.Length(); i++) {
+				for (uint i = 0; i < f->param_info.size(); i++) {
 					if (f->param_info[i] == NULL) {
 						*c->param_info.Append() = NULL;
 					} else {