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diff --git a/src/core/lib/support/manual_constructor.h b/src/core/lib/support/manual_constructor.h
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+++ b/src/core/lib/support/manual_constructor.h
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+/*
+ *
+ * Copyright 2016 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#ifndef GRPC_CORE_LIB_SUPPORT_MANUAL_CONSTRUCTOR_H
+#define GRPC_CORE_LIB_SUPPORT_MANUAL_CONSTRUCTOR_H
+
+// manually construct a region of memory with some type
+
+#include <stddef.h>
+#include <new>
+#include <type_traits>
+#include <utility>
+
+namespace grpc_core {
+
+template <typename Type>
+class ManualConstructor {
+ public:
+  // No constructor or destructor because one of the most useful uses of
+  // this class is as part of a union, and members of a union could not have
+  // constructors or destructors till C++11.  And, anyway, the whole point of
+  // this class is to bypass constructor and destructor.
+
+  Type* get() { return reinterpret_cast<Type*>(&space_); }
+  const Type* get() const { return reinterpret_cast<const Type*>(&space_); }
+
+  Type* operator->() { return get(); }
+  const Type* operator->() const { return get(); }
+
+  Type& operator*() { return *get(); }
+  const Type& operator*() const { return *get(); }
+
+  void Init() { new (&space_) Type; }
+
+  // Init() constructs the Type instance using the given arguments
+  // (which are forwarded to Type's constructor).
+  //
+  // Note that Init() with no arguments performs default-initialization,
+  // not zero-initialization (i.e it behaves the same as "new Type;", not
+  // "new Type();"), so it will leave non-class types uninitialized.
+  template <typename... Ts>
+  void Init(Ts&&... args) {
+    new (&space_) Type(std::forward<Ts>(args)...);
+  }
+
+  // Init() that is equivalent to copy and move construction.
+  // Enables usage like this:
+  //   ManualConstructor<std::vector<int>> v;
+  //   v.Init({1, 2, 3});
+  void Init(const Type& x) { new (&space_) Type(x); }
+  void Init(Type&& x) { new (&space_) Type(std::move(x)); }
+
+  void Destroy() { get()->~Type(); }
+
+ private:
+  typename std::aligned_storage<sizeof(Type), alignof(Type)>::type space_;
+};
+
+}  // namespace grpc_core
+
+#endif