diff --git a/src/plugins/debugger/cdb/cdbengine.h b/src/plugins/debugger/cdb/cdbengine.h
index bd83105df7b..fd0e35ba8a3 100644
--- a/src/plugins/debugger/cdb/cdbengine.h
+++ b/src/plugins/debugger/cdb/cdbengine.h
@@ -38,8 +38,6 @@ namespace Debugger {
 namespace Internal {
 
 class CdbCommand;
-struct MemoryViewCookie;
-class StringInputStream;
 
 class CdbEngine : public CppDebuggerEngine
 {