diff --git a/src/ConnectCommand.h b/src/ConnectCommand.h
index 003f9b07..56cffb88 100644
--- a/src/ConnectCommand.h
+++ b/src/ConnectCommand.h
@@ -40,7 +40,7 @@
 
 namespace aria2 {
 
-class BackupConnectInfo;
+struct BackupConnectInfo;
 
 class ConnectCommand : public AbstractCommand {
 public:
diff --git a/src/IndexedList.h b/src/IndexedList.h
index 7108736b..46d8cea7 100644
--- a/src/IndexedList.h
+++ b/src/IndexedList.h
@@ -64,8 +64,8 @@ struct IndexedListIterator {
   typedef ValueType value_type;
   typedef PointerType pointer;
   typedef ReferenceType reference;
-  typedef typename SeqIteratorType::size_type size_type;
-  typedef typename SeqIteratorType::difference_type difference_type;
+  typedef typename SeqType::size_type size_type;
+  typedef typename SeqType::difference_type difference_type;
   typedef IndexedListIterator SelfType;
 
   IndexedListIterator() {}
diff --git a/src/InitiateConnectionCommand.h b/src/InitiateConnectionCommand.h
index 0dcaca4a..6c77d5bb 100644
--- a/src/InitiateConnectionCommand.h
+++ b/src/InitiateConnectionCommand.h
@@ -39,7 +39,7 @@
 
 namespace aria2 {
 
-class BackupConnectInfo;
+struct BackupConnectInfo;
 class ConnectCommand;
 
 class InitiateConnectionCommand : public AbstractCommand {