diff --git a/include/llvm/CodeGen/MachineBasicBlock.h b/include/llvm/CodeGen/MachineBasicBlock.h
index 85d348337a9..1196f2126b6 100644
--- a/include/llvm/CodeGen/MachineBasicBlock.h
+++ b/include/llvm/CodeGen/MachineBasicBlock.h
@@ -222,6 +222,7 @@ private:   // Methods used to maintain doubly linked list of blocks...
   void removePredecessor(MachineBasicBlock *pred);
 };
 
+std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB);
 
 
 //===--------------------------------------------------------------------===//
diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h
index b967a1fcb37..907985877f0 100644
--- a/include/llvm/CodeGen/MachineInstr.h
+++ b/include/llvm/CodeGen/MachineInstr.h
@@ -20,6 +20,7 @@
 #include "llvm/Support/DataTypes.h"
 #include <vector>
 #include <cassert>
+#include <iosfwd>
 
 namespace llvm {
 
diff --git a/lib/CodeGen/MachineBasicBlock.cpp b/lib/CodeGen/MachineBasicBlock.cpp
index fcc01299cd8..201b79e1300 100644
--- a/lib/CodeGen/MachineBasicBlock.cpp
+++ b/lib/CodeGen/MachineBasicBlock.cpp
@@ -27,6 +27,10 @@ MachineBasicBlock::~MachineBasicBlock() {
   LeakDetector::removeGarbageObject(this);
 }
 
+std::ostream& llvm::operator<<(std::ostream &OS, const MachineBasicBlock &MBB) {
+  MBB.print(OS);
+  return OS;
+}
 
 // MBBs start out as #-1. When a MBB is added to a MachineFunction, it
 // gets the next available unique MBB number. If it is removed from a