diff --git a/llvm/include/llvm/ADT/Optional.h b/llvm/include/llvm/ADT/Optional.h
--- a/llvm/include/llvm/ADT/Optional.h
+++ b/llvm/include/llvm/ADT/Optional.h
@@ -23,13 +23,10 @@
 #include "llvm/Support/type_traits.h"
 #include <cassert>
 #include <new>
-#include <optional>
 #include <utility>
 
 namespace llvm {
 
-class raw_ostream;
-
 namespace optional_detail {
 
 /// Storage for any type.
@@ -479,28 +476,6 @@
   return !(X < Y);
 }
 
-raw_ostream &operator<<(raw_ostream &OS, std::nullopt_t);
-
-template <typename T, typename = decltype(std::declval<raw_ostream &>()
-                                          << std::declval<const T &>())>
-raw_ostream &operator<<(raw_ostream &OS, const Optional<T> &O) {
-  if (O)
-    OS << *O;
-  else
-    OS << std::nullopt;
-  return OS;
-}
-
-template <typename T, typename = decltype(std::declval<raw_ostream &>()
-                                          << std::declval<const T &>())>
-raw_ostream &operator<<(raw_ostream &OS, const std::optional<T> &O) {
-  if (O)
-    OS << *O;
-  else
-    OS << std::nullopt;
-  return OS;
-}
-
 } // end namespace llvm
 
 #endif // LLVM_ADT_OPTIONAL_H
diff --git a/llvm/include/llvm/Support/raw_ostream.h b/llvm/include/llvm/Support/raw_ostream.h
--- a/llvm/include/llvm/Support/raw_ostream.h
+++ b/llvm/include/llvm/Support/raw_ostream.h
@@ -13,6 +13,7 @@
 #ifndef LLVM_SUPPORT_RAW_OSTREAM_H
 #define LLVM_SUPPORT_RAW_OSTREAM_H
 
+#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/DataTypes.h"
@@ -740,6 +741,28 @@
 Error writeToOutput(StringRef OutputFileName,
                     std::function<Error(raw_ostream &)> Write);
 
+raw_ostream &operator<<(raw_ostream &OS, std::nullopt_t);
+
+template <typename T, typename = decltype(std::declval<raw_ostream &>()
+                                          << std::declval<const T &>())>
+raw_ostream &operator<<(raw_ostream &OS, const Optional<T> &O) {
+  if (O)
+    OS << *O;
+  else
+    OS << std::nullopt;
+  return OS;
+}
+
+template <typename T, typename = decltype(std::declval<raw_ostream &>()
+                                          << std::declval<const T &>())>
+raw_ostream &operator<<(raw_ostream &OS, const std::optional<T> &O) {
+  if (O)
+    OS << *O;
+  else
+    OS << std::nullopt;
+  return OS;
+}
+
 } // end namespace llvm
 
 #endif // LLVM_SUPPORT_RAW_OSTREAM_H