diff --git a/lib/CodeGen/InstrSched/SchedPriorities.h b/lib/CodeGen/InstrSched/SchedPriorities.h
index 1366884..7cfcb03 100644
--- a/lib/CodeGen/InstrSched/SchedPriorities.h
+++ b/lib/CodeGen/InstrSched/SchedPriorities.h
@@ -18,6 +18,7 @@
 #include "llvm/Target/MachineSchedInfo.h"
 #include "Support/hash_set"
 #include <list>
+#include <iosfwd>
 
 class Function;
 class MachineInstr;
diff --git a/lib/Target/SparcV9/InstrSched/SchedPriorities.h b/lib/Target/SparcV9/InstrSched/SchedPriorities.h
index 1366884..7cfcb03 100644
--- a/lib/Target/SparcV9/InstrSched/SchedPriorities.h
+++ b/lib/Target/SparcV9/InstrSched/SchedPriorities.h
@@ -18,6 +18,7 @@
 #include "llvm/Target/MachineSchedInfo.h"
 #include "Support/hash_set"
 #include <list>
+#include <iosfwd>
 
 class Function;
 class MachineInstr;