diff --git a/Kernel/Forward.h b/Kernel/Forward.h
index 494dda897d..7d8330ce74 100644
--- a/Kernel/Forward.h
+++ b/Kernel/Forward.h
@@ -31,6 +31,7 @@ class InodeWatcher;
 class KBuffer;
 class KResult;
 class LocalSocket;
+class MemoryManager;
 class Mutex;
 class MappedROM;
 class MasterPTY;