diff --git a/include/llvm/CodeGen/ScheduleDAG.h b/include/llvm/CodeGen/ScheduleDAG.h
index c3e973113e5..37f33a1a2fc 100644
--- a/include/llvm/CodeGen/ScheduleDAG.h
+++ b/include/llvm/CodeGen/ScheduleDAG.h
@@ -18,7 +18,7 @@
 #include "llvm/CodeGen/SelectionDAG.h"
 
 namespace llvm {
-  class InstrStage;
+  struct InstrStage;
   class MachineConstantPool;
   class MachineDebugInfo;
   class MachineInstr;