diff --git a/lib/VMCore/AsmWriter.cpp b/lib/VMCore/AsmWriter.cpp
index 8ff55b66409..50526c39594 100644
--- a/lib/VMCore/AsmWriter.cpp
+++ b/lib/VMCore/AsmWriter.cpp
@@ -26,10 +26,11 @@
 #include "llvm/Instructions.h"
 #include "llvm/Module.h"
 #include "llvm/SymbolTable.h"
-#include "llvm/Support/CFG.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/STLExtras.h"
+#include "llvm/Support/CFG.h"
 #include "llvm/Support/MathExtras.h"
+#include "llvm/Support/Streams.h"
 #include <algorithm>
 using namespace llvm;
 
@@ -866,7 +867,7 @@ void AssemblyWriter::printGlobal(const GlobalVariable *GV) {
     case GlobalValue::ExternalWeakLinkage: Out << "extern_weak "; break;
     case GlobalValue::ExternalLinkage:     break;
     case GlobalValue::GhostLinkage:
-      std::cerr << "GhostLinkage not allowed in AsmWriter!\n";
+      llvm_cerr << "GhostLinkage not allowed in AsmWriter!\n";
       abort();
     }
 
@@ -965,7 +966,7 @@ void AssemblyWriter::printFunction(const Function *F) {
     case GlobalValue::ExternalWeakLinkage: Out << "extern_weak "; break;      
     case GlobalValue::ExternalLinkage: break;
     case GlobalValue::GhostLinkage:
-      std::cerr << "GhostLinkage not allowed in AsmWriter!\n";
+      llvm_cerr << "GhostLinkage not allowed in AsmWriter!\n";
       abort();
     }
 
@@ -1358,11 +1359,11 @@ void Argument::print(std::ostream &o) const {
 
 // Value::dump - allow easy printing of  Values from the debugger.
 // Located here because so much of the needed functionality is here.
-void Value::dump() const { print(std::cerr); std::cerr << '\n'; }
+void Value::dump() const { print(std::cerr); llvm_cerr << '\n'; }
 
 // Type::dump - allow easy printing of  Values from the debugger.
 // Located here because so much of the needed functionality is here.
-void Type::dump() const { print(std::cerr); std::cerr << '\n'; }
+void Type::dump() const { print(std::cerr); llvm_cerr << '\n'; }
 
 //===----------------------------------------------------------------------===//
 //  CachedWriter Class Implementation
@@ -1413,7 +1414,7 @@ CachedWriter& CachedWriter::operator<<(const Type &Ty) {
 //===----------------------------------------------------------------------===//
 
 #if 0
-#define SC_DEBUG(X) std::cerr << X
+#define SC_DEBUG(X) llvm_cerr << X
 #else
 #define SC_DEBUG(X)
 #endif
diff --git a/lib/VMCore/AutoUpgrade.cpp b/lib/VMCore/AutoUpgrade.cpp
index 57a09e2d07f..9f7f818e7ff 100644
--- a/lib/VMCore/AutoUpgrade.cpp
+++ b/lib/VMCore/AutoUpgrade.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Assembly/AutoUpgrade.h"
+#include "llvm/Support/Streams.h"
 #include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/Function.h"
@@ -19,7 +20,6 @@
 #include "llvm/Instructions.h"
 #include "llvm/Intrinsics.h"
 #include "llvm/SymbolTable.h"
-#include <iostream>
 using namespace llvm;
 
 static Function *getUpgradedUnaryFn(Function *F) {
@@ -193,7 +193,7 @@ Function *llvm::UpgradeIntrinsicFunction(Function* F) {
   // See if its one of the name's we're interested in.
   if (Function *R = getUpgradedIntrinsic(F)) {
     if (R->getName() != F->getName())
-      std::cerr << "WARNING: change " << F->getName() << " to "
+      llvm_cerr << "WARNING: change " << F->getName() << " to "
                 << R->getName() << "\n";
     return R;
   }
diff --git a/lib/VMCore/LeakDetector.cpp b/lib/VMCore/LeakDetector.cpp
index 39715fe48ce..4c9f1258072 100644
--- a/lib/VMCore/LeakDetector.cpp
+++ b/lib/VMCore/LeakDetector.cpp
@@ -11,22 +11,22 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/Support/LeakDetector.h"
 #include "llvm/Support/Compiler.h"
+#include "llvm/Support/LeakDetector.h"
+#include "llvm/Support/Streams.h"
 #include "llvm/Value.h"
-#include <iostream>
 #include <set>
 using namespace llvm;
 
 namespace {
   template <class T>
   struct VISIBILITY_HIDDEN PrinterTrait {
-    static void print(const T* P) { std::cerr << P; }
+    static void print(const T* P) { llvm_cerr << P; }
   };
 
   template<>
   struct VISIBILITY_HIDDEN PrinterTrait<Value> {
-    static void print(const Value* P) { std::cerr << *P; }
+    static void print(const Value* P) { llvm_cerr << *P; }
   };
 
   template <typename T>
@@ -59,15 +59,15 @@ namespace {
       assert(Cache == 0 && "No value should be cached anymore!");
 
       if (!Ts.empty()) {
-        std::cerr
+        llvm_cerr
             << "Leaked " << Name << " objects found: " << Message << ":\n";
         for (typename std::set<const T*>::iterator I = Ts.begin(),
                E = Ts.end(); I != E; ++I) {
-          std::cerr << "\t";
+          llvm_cerr << "\t";
           PrinterTrait<T>::print(*I);
-          std::cerr << "\n";
+          llvm_cerr << "\n";
         }
-        std::cerr << '\n';
+        llvm_cerr << '\n';
 
         return true;
       }
@@ -123,8 +123,8 @@ void LeakDetector::checkForGarbageImpl(const std::string &Message) {
   // use non-short-circuit version so that both checks are performed
   if (getObjects().hasGarbage(Message) |
       getLLVMObjects().hasGarbage(Message))
-    std::cerr << "\nThis is probably because you removed an object, but didn't "
-                 "delete it.  Please check your code for memory leaks.\n";
+    llvm_cerr << "\nThis is probably because you removed an object, but didn't "
+              << "delete it.  Please check your code for memory leaks.\n";
 
   // Clear out results so we don't get duplicate warnings on
   // next call...
diff --git a/lib/VMCore/PassManager.cpp b/lib/VMCore/PassManager.cpp
index b8717ea42f7..d01ef3e4a7b 100644
--- a/lib/VMCore/PassManager.cpp
+++ b/lib/VMCore/PassManager.cpp
@@ -15,10 +15,9 @@
 #include "llvm/PassManager.h"
 #include "llvm/Module.h"
 #include "llvm/ModuleProvider.h"
+#include "llvm/Support/Streams.h"
 #include <vector>
 #include <map>
-#include <iostream>
-
 using namespace llvm;
 
 namespace llvm {
@@ -443,7 +442,7 @@ bool FunctionPassManager_New::runOnModule(Module &M) {
 bool FunctionPassManager_New::run(Function &F) {
   std::string errstr;
   if (MP->materializeFunction(&F, &errstr)) {
-    std::cerr << "Error reading bytecode file: " << errstr << "\n";
+    llvm_cerr << "Error reading bytecode file: " << errstr << "\n";
     abort();
   }
   return FPM->runOnFunction(F);
diff --git a/lib/VMCore/TypeSymbolTable.cpp b/lib/VMCore/TypeSymbolTable.cpp
index b608c18ae5e..7af7bea407a 100644
--- a/lib/VMCore/TypeSymbolTable.cpp
+++ b/lib/VMCore/TypeSymbolTable.cpp
@@ -14,9 +14,8 @@
 #include "llvm/TypeSymbolTable.h"
 #include "llvm/DerivedTypes.h"
 #include "llvm/ADT/StringExtras.h"
-#include <iostream>
+#include "llvm/Support/Streams.h"
 #include <algorithm>
-
 using namespace llvm;
 
 #define DEBUG_SYMBOL_TABLE 0
@@ -67,7 +66,7 @@ Type* TypeSymbolTable::erase(iterator Entry) {
 
 #if DEBUG_SYMBOL_TABLE
   dump();
-  std::cerr << " Removing Value: " << Result->getName() << "\n";
+  llvm_cerr << " Removing Value: " << Result->getName() << "\n";
 #endif
 
   tmap.erase(Entry);
@@ -76,7 +75,7 @@ Type* TypeSymbolTable::erase(iterator Entry) {
   // list...
   if (Result->isAbstract()) {
 #if DEBUG_ABSTYPE
-    std::cerr << "Removing abstract type from symtab" << Result->getDescription()<<"\n";
+    llvm_cerr << "Removing abstract type from symtab" << Result->getDescription()<<"\n";
 #endif
     cast<DerivedType>(Result)->removeAbstractTypeUser(this);
   }
@@ -96,7 +95,7 @@ void TypeSymbolTable::insert(const std::string& Name, const Type* T) {
 
 #if DEBUG_SYMBOL_TABLE
   dump();
-  std::cerr << " Inserting type: " << UniqueName << ": "
+  llvm_cerr << " Inserting type: " << UniqueName << ": "
             << T->getDescription() << "\n";
 #endif
 
@@ -107,7 +106,7 @@ void TypeSymbolTable::insert(const std::string& Name, const Type* T) {
   if (T->isAbstract()) {
     cast<DerivedType>(T)->addAbstractTypeUser(this);
 #if DEBUG_ABSTYPE
-    std::cerr << "Added abstract type to ST: " << T->getDescription() << "\n";
+    llvm_cerr << "Added abstract type to ST: " << T->getDescription() << "\n";
 #endif
   }
 }
@@ -153,14 +152,14 @@ void TypeSymbolTable::refineAbstractType(const DerivedType *OldType,
   for (iterator I = begin(), E = end(); I != E; ++I) {
     if (I->second == (Type*)OldType) {  // FIXME when Types aren't const.
 #if DEBUG_ABSTYPE
-      std::cerr << "Removing type " << OldType->getDescription() << "\n";
+      llvm_cerr << "Removing type " << OldType->getDescription() << "\n";
 #endif
       OldType->removeAbstractTypeUser(this);
 
       I->second = (Type*)NewType;  // TODO FIXME when types aren't const
       if (NewType->isAbstract()) {
 #if DEBUG_ABSTYPE
-        std::cerr << "Added type " << NewType->getDescription() << "\n";
+        llvm_cerr << "Added type " << NewType->getDescription() << "\n";
 #endif
         cast<DerivedType>(NewType)->addAbstractTypeUser(this);
       }
@@ -180,13 +179,13 @@ void TypeSymbolTable::typeBecameConcrete(const DerivedType *AbsTy) {
 }
 
 static void DumpTypes(const std::pair<const std::string, const Type*>& T ) {
-  std::cerr << "  '" << T.first << "' = ";
+  llvm_cerr << "  '" << T.first << "' = ";
   T.second->dump();
-  std::cerr << "\n";
+  llvm_cerr << "\n";
 }
 
 void TypeSymbolTable::dump() const {
-  std::cerr << "TypeSymbolPlane: ";
+  llvm_cerr << "TypeSymbolPlane: ";
   for_each(tmap.begin(), tmap.end(), DumpTypes);
 }
 
diff --git a/lib/VMCore/Verifier.cpp b/lib/VMCore/Verifier.cpp
index d57cd515960..f1e14a64bc6 100644
--- a/lib/VMCore/Verifier.cpp
+++ b/lib/VMCore/Verifier.cpp
@@ -55,11 +55,11 @@
 #include "llvm/Analysis/Dominators.h"
 #include "llvm/Support/CFG.h"
 #include "llvm/Support/InstVisitor.h"
+#include "llvm/Support/Streams.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/Compiler.h"
 #include <algorithm>
-#include <iostream>
 #include <sstream>
 #include <cstdarg>
 using namespace llvm;
@@ -156,11 +156,11 @@ namespace {  // Anonymous namespace for class
         switch (action) {
           case AbortProcessAction:
             msgs << "compilation aborted!\n";
-            std::cerr << msgs.str();
+            llvm_cerr << msgs.str();
             abort();
           case PrintMessageAction:
             msgs << "verification continues.\n";
-            std::cerr << msgs.str();
+            llvm_cerr << msgs.str();
             return false;
           case ReturnStatusAction:
             msgs << "compilation terminated.\n";