we'd better use vcpkg instead of adding shit to our repo....

17 files changed, 0 insertions, 5088 deletions

diff --git a/include/google/protobuf/stubs/bytestream.h b/include/google/protobuf/stubs/bytestream.h
deleted file mode 100644
index c7a48dea54..0000000000
--- a/include/google/protobuf/stubs/bytestream.h
+++ /dev/null
@@ -1,351 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// This file declares the ByteSink and ByteSource abstract interfaces. These
-// interfaces represent objects that consume (ByteSink) or produce (ByteSource)
-// a sequence of bytes. Using these abstract interfaces in your APIs can help
-// make your code work with a variety of input and output types.
-//
-// This file also declares the following commonly used implementations of these
-// interfaces.
-//
-//   ByteSink:
-//      UncheckedArrayByteSink  Writes to an array, without bounds checking
-//      CheckedArrayByteSink    Writes to an array, with bounds checking
-//      GrowingArrayByteSink    Allocates and writes to a growable buffer
-//      StringByteSink          Writes to an STL string
-//      NullByteSink            Consumes a never-ending stream of bytes
-//
-//   ByteSource:
-//      ArrayByteSource         Reads from an array or string/StringPiece
-//      LimitedByteSource       Limits the number of bytes read from an
-
-#ifndef GOOGLE_PROTOBUF_STUBS_BYTESTREAM_H_
-#define GOOGLE_PROTOBUF_STUBS_BYTESTREAM_H_
-
-#include <stddef.h>
-#include <string>
-
-#include <google/protobuf/stubs/common.h>
-#include <google/protobuf/stubs/stringpiece.h>
-
-#include <google/protobuf/port_def.inc>
-
-class CordByteSink;
-
-namespace google {
-namespace protobuf {
-namespace strings {
-
-// An abstract interface for an object that consumes a sequence of bytes. This
-// interface offers a way to append data as well as a Flush() function.
-//
-// Example:
-//
-//   string my_data;
-//   ...
-//   ByteSink* sink = ...
-//   sink->Append(my_data.data(), my_data.size());
-//   sink->Flush();
-//
-class PROTOBUF_EXPORT ByteSink {
- public:
-  ByteSink() {}
-  virtual ~ByteSink() {}
-
-  // Appends the "n" bytes starting at "bytes".
-  virtual void Append(const char* bytes, size_t n) = 0;
-
-  // Flushes internal buffers. The default implementation does nothing. ByteSink
-  // subclasses may use internal buffers that require calling Flush() at the end
-  // of the stream.
-  virtual void Flush();
-
- private:
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ByteSink);
-};
-
-// An abstract interface for an object that produces a fixed-size sequence of
-// bytes.
-//
-// Example:
-//
-//   ByteSource* source = ...
-//   while (source->Available() > 0) {
-//     StringPiece data = source->Peek();
-//     ... do something with "data" ...
-//     source->Skip(data.length());
-//   }
-//
-class PROTOBUF_EXPORT ByteSource {
- public:
-  ByteSource() {}
-  virtual ~ByteSource() {}
-
-  // Returns the number of bytes left to read from the source. Available()
-  // should decrease by N each time Skip(N) is called. Available() may not
-  // increase. Available() returning 0 indicates that the ByteSource is
-  // exhausted.
-  //
-  // Note: Size() may have been a more appropriate name as it's more
-  //       indicative of the fixed-size nature of a ByteSource.
-  virtual size_t Available() const = 0;
-
-  // Returns a StringPiece of the next contiguous region of the source. Does not
-  // reposition the source. The returned region is empty iff Available() == 0.
-  //
-  // The returned region is valid until the next call to Skip() or until this
-  // object is destroyed, whichever occurs first.
-  //
-  // The length of the returned StringPiece will be <= Available().
-  virtual StringPiece Peek() = 0;
-
-  // Skips the next n bytes. Invalidates any StringPiece returned by a previous
-  // call to Peek().
-  //
-  // REQUIRES: Available() >= n
-  virtual void Skip(size_t n) = 0;
-
-  // Writes the next n bytes in this ByteSource to the given ByteSink, and
-  // advances this ByteSource past the copied bytes. The default implementation
-  // of this method just copies the bytes normally, but subclasses might
-  // override CopyTo to optimize certain cases.
-  //
-  // REQUIRES: Available() >= n
-  virtual void CopyTo(ByteSink* sink, size_t n);
-
- private:
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ByteSource);
-};
-
-//
-// Some commonly used implementations of ByteSink
-//
-
-// Implementation of ByteSink that writes to an unsized byte array. No
-// bounds-checking is performed--it is the caller's responsibility to ensure
-// that the destination array is large enough.
-//
-// Example:
-//
-//   char buf[10];
-//   UncheckedArrayByteSink sink(buf);
-//   sink.Append("hi", 2);    // OK
-//   sink.Append(data, 100);  // WOOPS! Overflows buf[10].
-//
-class PROTOBUF_EXPORT UncheckedArrayByteSink : public ByteSink {
- public:
-  explicit UncheckedArrayByteSink(char* dest) : dest_(dest) {}
-  virtual void Append(const char* data, size_t n) override;
-
-  // Returns the current output pointer so that a caller can see how many bytes
-  // were produced.
-  //
-  // Note: this method is not part of the ByteSink interface.
-  char* CurrentDestination() const { return dest_; }
-
- private:
-  char* dest_;
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(UncheckedArrayByteSink);
-};
-
-// Implementation of ByteSink that writes to a sized byte array. This sink will
-// not write more than "capacity" bytes to outbuf. Once "capacity" bytes are
-// appended, subsequent bytes will be ignored and Overflowed() will return true.
-// Overflowed() does not cause a runtime error (i.e., it does not CHECK fail).
-//
-// Example:
-//
-//   char buf[10];
-//   CheckedArrayByteSink sink(buf, 10);
-//   sink.Append("hi", 2);    // OK
-//   sink.Append(data, 100);  // Will only write 8 more bytes
-//
-class PROTOBUF_EXPORT CheckedArrayByteSink : public ByteSink {
- public:
-  CheckedArrayByteSink(char* outbuf, size_t capacity);
-  virtual void Append(const char* bytes, size_t n) override;
-
-  // Returns the number of bytes actually written to the sink.
-  size_t NumberOfBytesWritten() const { return size_; }
-
-  // Returns true if any bytes were discarded, i.e., if there was an
-  // attempt to write more than 'capacity' bytes.
-  bool Overflowed() const { return overflowed_; }
-
- private:
-  char* outbuf_;
-  const size_t capacity_;
-  size_t size_;
-  bool overflowed_;
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(CheckedArrayByteSink);
-};
-
-// Implementation of ByteSink that allocates an internal buffer (a char array)
-// and expands it as needed to accommodate appended data (similar to a string),
-// and allows the caller to take ownership of the internal buffer via the
-// GetBuffer() method. The buffer returned from GetBuffer() must be deleted by
-// the caller with delete[]. GetBuffer() also sets the internal buffer to be
-// empty, and subsequent appends to the sink will create a new buffer. The
-// destructor will free the internal buffer if GetBuffer() was not called.
-//
-// Example:
-//
-//   GrowingArrayByteSink sink(10);
-//   sink.Append("hi", 2);
-//   sink.Append(data, n);
-//   const char* buf = sink.GetBuffer();  // Ownership transferred
-//   delete[] buf;
-//
-class PROTOBUF_EXPORT GrowingArrayByteSink : public strings::ByteSink {
- public:
-  explicit GrowingArrayByteSink(size_t estimated_size);
-  virtual ~GrowingArrayByteSink();
-  virtual void Append(const char* bytes, size_t n) override;
-
-  // Returns the allocated buffer, and sets nbytes to its size. The caller takes
-  // ownership of the buffer and must delete it with delete[].
-  char* GetBuffer(size_t* nbytes);
-
- private:
-  void Expand(size_t amount);
-  void ShrinkToFit();
-
-  size_t capacity_;
-  char* buf_;
-  size_t size_;
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(GrowingArrayByteSink);
-};
-
-// Implementation of ByteSink that appends to the given string.
-// Existing contents of "dest" are not modified; new data is appended.
-//
-// Example:
-//
-//   string dest = "Hello ";
-//   StringByteSink sink(&dest);
-//   sink.Append("World", 5);
-//   assert(dest == "Hello World");
-//
-class PROTOBUF_EXPORT StringByteSink : public ByteSink {
- public:
-  explicit StringByteSink(std::string* dest) : dest_(dest) {}
-  virtual void Append(const char* data, size_t n) override;
-
- private:
-  std::string* dest_;
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(StringByteSink);
-};
-
-// Implementation of ByteSink that discards all data.
-//
-// Example:
-//
-//   NullByteSink sink;
-//   sink.Append(data, data.size());  // All data ignored.
-//
-class PROTOBUF_EXPORT NullByteSink : public ByteSink {
- public:
-  NullByteSink() {}
-  void Append(const char* /*data*/, size_t /*n*/) override {}
-
- private:
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(NullByteSink);
-};
-
-//
-// Some commonly used implementations of ByteSource
-//
-
-// Implementation of ByteSource that reads from a StringPiece.
-//
-// Example:
-//
-//   string data = "Hello";
-//   ArrayByteSource source(data);
-//   assert(source.Available() == 5);
-//   assert(source.Peek() == "Hello");
-//
-class PROTOBUF_EXPORT ArrayByteSource : public ByteSource {
- public:
-  explicit ArrayByteSource(StringPiece s) : input_(s) {}
-
-  virtual size_t Available() const override;
-  virtual StringPiece Peek() override;
-  virtual void Skip(size_t n) override;
-
- private:
-  StringPiece   input_;
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ArrayByteSource);
-};
-
-// Implementation of ByteSource that wraps another ByteSource, limiting the
-// number of bytes returned.
-//
-// The caller maintains ownership of the underlying source, and may not use the
-// underlying source while using the LimitByteSource object.  The underlying
-// source's pointer is advanced by n bytes every time this LimitByteSource
-// object is advanced by n.
-//
-// Example:
-//
-//   string data = "Hello World";
-//   ArrayByteSource abs(data);
-//   assert(abs.Available() == data.size());
-//
-//   LimitByteSource limit(abs, 5);
-//   assert(limit.Available() == 5);
-//   assert(limit.Peek() == "Hello");
-//
-class PROTOBUF_EXPORT LimitByteSource : public ByteSource {
- public:
-  // Returns at most "limit" bytes from "source".
-  LimitByteSource(ByteSource* source, size_t limit);
-
-  virtual size_t Available() const override;
-  virtual StringPiece Peek() override;
-  virtual void Skip(size_t n) override;
-
-  // We override CopyTo so that we can forward to the underlying source, in
-  // case it has an efficient implementation of CopyTo.
-  virtual void CopyTo(ByteSink* sink, size_t n) override;
-
- private:
-  ByteSource* source_;
-  size_t limit_;
-};
-
-}  // namespace strings
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_BYTESTREAM_H_
diff --git a/include/google/protobuf/stubs/callback.h b/include/google/protobuf/stubs/callback.h
deleted file mode 100644
index 43d546d199..0000000000
--- a/include/google/protobuf/stubs/callback.h
+++ /dev/null
@@ -1,583 +0,0 @@
-#ifndef GOOGLE_PROTOBUF_STUBS_CALLBACK_H_
-#define GOOGLE_PROTOBUF_STUBS_CALLBACK_H_
-
-#include <type_traits>
-
-#include <google/protobuf/stubs/macros.h>
-
-#include <google/protobuf/port_def.inc>
-
-// ===================================================================
-// emulates google3/base/callback.h
-
-namespace google {
-namespace protobuf {
-
-// Abstract interface for a callback.  When calling an RPC, you must provide
-// a Closure to call when the procedure completes.  See the Service interface
-// in service.h.
-//
-// To automatically construct a Closure which calls a particular function or
-// method with a particular set of parameters, use the NewCallback() function.
-// Example:
-//   void FooDone(const FooResponse* response) {
-//     ...
-//   }
-//
-//   void CallFoo() {
-//     ...
-//     // When done, call FooDone() and pass it a pointer to the response.
-//     Closure* callback = NewCallback(&FooDone, response);
-//     // Make the call.
-//     service->Foo(controller, request, response, callback);
-//   }
-//
-// Example that calls a method:
-//   class Handler {
-//    public:
-//     ...
-//
-//     void FooDone(const FooResponse* response) {
-//       ...
-//     }
-//
-//     void CallFoo() {
-//       ...
-//       // When done, call FooDone() and pass it a pointer to the response.
-//       Closure* callback = NewCallback(this, &Handler::FooDone, response);
-//       // Make the call.
-//       service->Foo(controller, request, response, callback);
-//     }
-//   };
-//
-// Currently NewCallback() supports binding zero, one, or two arguments.
-//
-// Callbacks created with NewCallback() automatically delete themselves when
-// executed.  They should be used when a callback is to be called exactly
-// once (usually the case with RPC callbacks).  If a callback may be called
-// a different number of times (including zero), create it with
-// NewPermanentCallback() instead.  You are then responsible for deleting the
-// callback (using the "delete" keyword as normal).
-//
-// Note that NewCallback() is a bit touchy regarding argument types.  Generally,
-// the values you provide for the parameter bindings must exactly match the
-// types accepted by the callback function.  For example:
-//   void Foo(std::string s);
-//   NewCallback(&Foo, "foo");          // WON'T WORK:  const char* != string
-//   NewCallback(&Foo, std::string("foo"));  // WORKS
-// Also note that the arguments cannot be references:
-//   void Foo(const std::string& s);
-//   std::string my_str;
-//   NewCallback(&Foo, my_str);  // WON'T WORK:  Can't use references.
-// However, correctly-typed pointers will work just fine.
-class PROTOBUF_EXPORT Closure {
- public:
-  Closure() {}
-  virtual ~Closure();
-
-  virtual void Run() = 0;
-
- private:
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(Closure);
-};
-
-template<typename R>
-class ResultCallback {
- public:
-  ResultCallback() {}
-  virtual ~ResultCallback() {}
-
-  virtual R Run() = 0;
-
- private:
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ResultCallback);
-};
-
-template <typename R, typename A1>
-class PROTOBUF_EXPORT ResultCallback1 {
- public:
-  ResultCallback1() {}
-  virtual ~ResultCallback1() {}
-
-  virtual R Run(A1) = 0;
-
- private:
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ResultCallback1);
-};
-
-template <typename R, typename A1, typename A2>
-class PROTOBUF_EXPORT ResultCallback2 {
- public:
-  ResultCallback2() {}
-  virtual ~ResultCallback2() {}
-
-  virtual R Run(A1,A2) = 0;
-
- private:
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ResultCallback2);
-};
-
-namespace internal {
-
-class PROTOBUF_EXPORT FunctionClosure0 : public Closure {
- public:
-  typedef void (*FunctionType)();
-
-  FunctionClosure0(FunctionType function, bool self_deleting)
-    : function_(function), self_deleting_(self_deleting) {}
-  ~FunctionClosure0();
-
-  void Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    function_();
-    if (needs_delete) delete this;
-  }
-
- private:
-  FunctionType function_;
-  bool self_deleting_;
-};
-
-template <typename Class>
-class MethodClosure0 : public Closure {
- public:
-  typedef void (Class::*MethodType)();
-
-  MethodClosure0(Class* object, MethodType method, bool self_deleting)
-    : object_(object), method_(method), self_deleting_(self_deleting) {}
-  ~MethodClosure0() {}
-
-  void Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    (object_->*method_)();
-    if (needs_delete) delete this;
-  }
-
- private:
-  Class* object_;
-  MethodType method_;
-  bool self_deleting_;
-};
-
-template <typename Arg1>
-class FunctionClosure1 : public Closure {
- public:
-  typedef void (*FunctionType)(Arg1 arg1);
-
-  FunctionClosure1(FunctionType function, bool self_deleting,
-                   Arg1 arg1)
-    : function_(function), self_deleting_(self_deleting),
-      arg1_(arg1) {}
-  ~FunctionClosure1() {}
-
-  void Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    function_(arg1_);
-    if (needs_delete) delete this;
-  }
-
- private:
-  FunctionType function_;
-  bool self_deleting_;
-  Arg1 arg1_;
-};
-
-template <typename Class, typename Arg1>
-class MethodClosure1 : public Closure {
- public:
-  typedef void (Class::*MethodType)(Arg1 arg1);
-
-  MethodClosure1(Class* object, MethodType method, bool self_deleting,
-                 Arg1 arg1)
-    : object_(object), method_(method), self_deleting_(self_deleting),
-      arg1_(arg1) {}
-  ~MethodClosure1() {}
-
-  void Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    (object_->*method_)(arg1_);
-    if (needs_delete) delete this;
-  }
-
- private:
-  Class* object_;
-  MethodType method_;
-  bool self_deleting_;
-  Arg1 arg1_;
-};
-
-template <typename Arg1, typename Arg2>
-class FunctionClosure2 : public Closure {
- public:
-  typedef void (*FunctionType)(Arg1 arg1, Arg2 arg2);
-
-  FunctionClosure2(FunctionType function, bool self_deleting,
-                   Arg1 arg1, Arg2 arg2)
-    : function_(function), self_deleting_(self_deleting),
-      arg1_(arg1), arg2_(arg2) {}
-  ~FunctionClosure2() {}
-
-  void Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    function_(arg1_, arg2_);
-    if (needs_delete) delete this;
-  }
-
- private:
-  FunctionType function_;
-  bool self_deleting_;
-  Arg1 arg1_;
-  Arg2 arg2_;
-};
-
-template <typename Class, typename Arg1, typename Arg2>
-class MethodClosure2 : public Closure {
- public:
-  typedef void (Class::*MethodType)(Arg1 arg1, Arg2 arg2);
-
-  MethodClosure2(Class* object, MethodType method, bool self_deleting,
-                 Arg1 arg1, Arg2 arg2)
-    : object_(object), method_(method), self_deleting_(self_deleting),
-      arg1_(arg1), arg2_(arg2) {}
-  ~MethodClosure2() {}
-
-  void Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    (object_->*method_)(arg1_, arg2_);
-    if (needs_delete) delete this;
-  }
-
- private:
-  Class* object_;
-  MethodType method_;
-  bool self_deleting_;
-  Arg1 arg1_;
-  Arg2 arg2_;
-};
-
-template<typename R>
-class FunctionResultCallback_0_0 : public ResultCallback<R> {
- public:
-  typedef R (*FunctionType)();
-
-  FunctionResultCallback_0_0(FunctionType function, bool self_deleting)
-      : function_(function), self_deleting_(self_deleting) {}
-  ~FunctionResultCallback_0_0() {}
-
-  R Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    R result = function_();
-    if (needs_delete) delete this;
-    return result;
-  }
-
- private:
-  FunctionType function_;
-  bool self_deleting_;
-};
-
-template<typename R, typename P1>
-class FunctionResultCallback_1_0 : public ResultCallback<R> {
- public:
-  typedef R (*FunctionType)(P1);
-
-  FunctionResultCallback_1_0(FunctionType function, bool self_deleting,
-                             P1 p1)
-      : function_(function), self_deleting_(self_deleting), p1_(p1) {}
-  ~FunctionResultCallback_1_0() {}
-
-  R Run() override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    R result = function_(p1_);
-    if (needs_delete) delete this;
-    return result;
-  }
-
- private:
-  FunctionType function_;
-  bool self_deleting_;
-  P1 p1_;
-};
-
-template<typename R, typename Arg1>
-class FunctionResultCallback_0_1 : public ResultCallback1<R, Arg1> {
- public:
-  typedef R (*FunctionType)(Arg1 arg1);
-
-  FunctionResultCallback_0_1(FunctionType function, bool self_deleting)
-      : function_(function), self_deleting_(self_deleting) {}
-  ~FunctionResultCallback_0_1() {}
-
-  R Run(Arg1 a1) override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    R result = function_(a1);
-    if (needs_delete) delete this;
-    return result;
-  }
-
- private:
-  FunctionType function_;
-  bool self_deleting_;
-};
-
-template<typename R, typename P1, typename A1>
-class FunctionResultCallback_1_1 : public ResultCallback1<R, A1> {
- public:
-  typedef R (*FunctionType)(P1, A1);
-
-  FunctionResultCallback_1_1(FunctionType function, bool self_deleting,
-                             P1 p1)
-      : function_(function), self_deleting_(self_deleting), p1_(p1) {}
-  ~FunctionResultCallback_1_1() {}
-
-  R Run(A1 a1) override {
-    bool needs_delete = self_deleting_;  // read in case callback deletes
-    R result = function_(p1_, a1);
-    if (needs_delete) delete this;
-    return result;
-  }
-
- private:
-  FunctionType function_;
-  bool self_deleting_;
-  P1 p1_;
-};
-
-template <typename T>
-struct InternalConstRef {
-  typedef typename std::remove_reference<T>::type base_type;
-  typedef const base_type& type;
-};
-
-template<typename R, typename T>
-class MethodResultCallback_0_0 : public ResultCallback<R> {
- public:
-  typedef R (T::*MethodType)();
-  MethodResultCallback_0_0(T* object, MethodType method, bool self_deleting)
-      : object_(object),
-        method_(method),
-        self_deleting_(self_deleting) {}
-  ~MethodResultCallback_0_0() {}
-
-  R Run() {
-    bool needs_delete = self_deleting_;
-    R result = (object_->*method_)();
-    if (needs_delete) delete this;
-    return result;
-  }
-
- private:
-  T* object_;
-  MethodType method_;
-  bool self_deleting_;
-};
-
-template <typename R, typename T, typename P1, typename P2, typename P3,
-          typename P4, typename P5, typename P6, typename A1, typename A2>
-class MethodResultCallback_6_2 : public ResultCallback2<R, A1, A2> {
- public:
-  typedef R (T::*MethodType)(P1, P2, P3, P4, P5, P6, A1, A2);
-  MethodResultCallback_6_2(T* object, MethodType method, bool self_deleting,
-                           P1 p1, P2 p2, P3 p3, P4 p4, P5 p5, P6 p6)
-      : object_(object),
-        method_(method),
-        self_deleting_(self_deleting),
-        p1_(p1),
-        p2_(p2),
-        p3_(p3),
-        p4_(p4),
-        p5_(p5),
-        p6_(p6) {}
-  ~MethodResultCallback_6_2() {}
-
-  R Run(A1 a1, A2 a2) override {
-    bool needs_delete = self_deleting_;
-    R result = (object_->*method_)(p1_, p2_, p3_, p4_, p5_, p6_, a1, a2);
-    if (needs_delete) delete this;
-    return result;
-  }
-
- private:
-  T* object_;
-  MethodType method_;
-  bool self_deleting_;
-  typename std::remove_reference<P1>::type p1_;
-  typename std::remove_reference<P2>::type p2_;
-  typename std::remove_reference<P3>::type p3_;
-  typename std::remove_reference<P4>::type p4_;
-  typename std::remove_reference<P5>::type p5_;
-  typename std::remove_reference<P6>::type p6_;
-};
-
-}  // namespace internal
-
-// See Closure.
-inline Closure* NewCallback(void (*function)()) {
-  return new internal::FunctionClosure0(function, true);
-}
-
-// See Closure.
-inline Closure* NewPermanentCallback(void (*function)()) {
-  return new internal::FunctionClosure0(function, false);
-}
-
-// See Closure.
-template <typename Class>
-inline Closure* NewCallback(Class* object, void (Class::*method)()) {
-  return new internal::MethodClosure0<Class>(object, method, true);
-}
-
-// See Closure.
-template <typename Class>
-inline Closure* NewPermanentCallback(Class* object, void (Class::*method)()) {
-  return new internal::MethodClosure0<Class>(object, method, false);
-}
-
-// See Closure.
-template <typename Arg1>
-inline Closure* NewCallback(void (*function)(Arg1),
-                            Arg1 arg1) {
-  return new internal::FunctionClosure1<Arg1>(function, true, arg1);
-}
-
-// See Closure.
-template <typename Arg1>
-inline Closure* NewPermanentCallback(void (*function)(Arg1),
-                                     Arg1 arg1) {
-  return new internal::FunctionClosure1<Arg1>(function, false, arg1);
-}
-
-// See Closure.
-template <typename Class, typename Arg1>
-inline Closure* NewCallback(Class* object, void (Class::*method)(Arg1),
-                            Arg1 arg1) {
-  return new internal::MethodClosure1<Class, Arg1>(object, method, true, arg1);
-}
-
-// See Closure.
-template <typename Class, typename Arg1>
-inline Closure* NewPermanentCallback(Class* object, void (Class::*method)(Arg1),
-                                     Arg1 arg1) {
-  return new internal::MethodClosure1<Class, Arg1>(object, method, false, arg1);
-}
-
-// See Closure.
-template <typename Arg1, typename Arg2>
-inline Closure* NewCallback(void (*function)(Arg1, Arg2),
-                            Arg1 arg1, Arg2 arg2) {
-  return new internal::FunctionClosure2<Arg1, Arg2>(
-    function, true, arg1, arg2);
-}
-
-// See Closure.
-template <typename Arg1, typename Arg2>
-inline Closure* NewPermanentCallback(void (*function)(Arg1, Arg2),
-                                     Arg1 arg1, Arg2 arg2) {
-  return new internal::FunctionClosure2<Arg1, Arg2>(
-    function, false, arg1, arg2);
-}
-
-// See Closure.
-template <typename Class, typename Arg1, typename Arg2>
-inline Closure* NewCallback(Class* object, void (Class::*method)(Arg1, Arg2),
-                            Arg1 arg1, Arg2 arg2) {
-  return new internal::MethodClosure2<Class, Arg1, Arg2>(
-    object, method, true, arg1, arg2);
-}
-
-// See Closure.
-template <typename Class, typename Arg1, typename Arg2>
-inline Closure* NewPermanentCallback(
-    Class* object, void (Class::*method)(Arg1, Arg2),
-    Arg1 arg1, Arg2 arg2) {
-  return new internal::MethodClosure2<Class, Arg1, Arg2>(
-    object, method, false, arg1, arg2);
-}
-
-// See ResultCallback
-template<typename R>
-inline ResultCallback<R>* NewCallback(R (*function)()) {
-  return new internal::FunctionResultCallback_0_0<R>(function, true);
-}
-
-// See ResultCallback
-template<typename R>
-inline ResultCallback<R>* NewPermanentCallback(R (*function)()) {
-  return new internal::FunctionResultCallback_0_0<R>(function, false);
-}
-
-// See ResultCallback
-template<typename R, typename P1>
-inline ResultCallback<R>* NewCallback(R (*function)(P1), P1 p1) {
-  return new internal::FunctionResultCallback_1_0<R, P1>(
-      function, true, p1);
-}
-
-// See ResultCallback
-template<typename R, typename P1>
-inline ResultCallback<R>* NewPermanentCallback(
-    R (*function)(P1), P1 p1) {
-  return new internal::FunctionResultCallback_1_0<R, P1>(
-      function, false, p1);
-}
-
-// See ResultCallback1
-template<typename R, typename A1>
-inline ResultCallback1<R, A1>* NewCallback(R (*function)(A1)) {
-  return new internal::FunctionResultCallback_0_1<R, A1>(function, true);
-}
-
-// See ResultCallback1
-template<typename R, typename A1>
-inline ResultCallback1<R, A1>* NewPermanentCallback(R (*function)(A1)) {
-  return new internal::FunctionResultCallback_0_1<R, A1>(function, false);
-}
-
-// See ResultCallback1
-template<typename R, typename P1, typename A1>
-inline ResultCallback1<R, A1>* NewCallback(R (*function)(P1, A1), P1 p1) {
-  return new internal::FunctionResultCallback_1_1<R, P1, A1>(
-      function, true, p1);
-}
-
-// See ResultCallback1
-template<typename R, typename P1, typename A1>
-inline ResultCallback1<R, A1>* NewPermanentCallback(
-    R (*function)(P1, A1), P1 p1) {
-  return new internal::FunctionResultCallback_1_1<R, P1, A1>(
-      function, false, p1);
-}
-
-// See MethodResultCallback_0_0
-template <typename R, typename T1, typename T2>
-inline ResultCallback<R>* NewPermanentCallback(
-    T1* object, R (T2::*function)()) {
-  return new internal::MethodResultCallback_0_0<R, T1>(object, function, false);
-}
-
-// See MethodResultCallback_6_2
-template <typename R, typename T, typename P1, typename P2, typename P3,
-          typename P4, typename P5, typename P6, typename A1, typename A2>
-inline ResultCallback2<R, A1, A2>* NewPermanentCallback(
-    T* object, R (T::*function)(P1, P2, P3, P4, P5, P6, A1, A2),
-    typename internal::InternalConstRef<P1>::type p1,
-    typename internal::InternalConstRef<P2>::type p2,
-    typename internal::InternalConstRef<P3>::type p3,
-    typename internal::InternalConstRef<P4>::type p4,
-    typename internal::InternalConstRef<P5>::type p5,
-    typename internal::InternalConstRef<P6>::type p6) {
-  return new internal::MethodResultCallback_6_2<R, T, P1, P2, P3, P4, P5, P6,
-                                                A1, A2>(object, function, false,
-                                                        p1, p2, p3, p4, p5, p6);
-}
-
-// A function which does nothing.  Useful for creating no-op callbacks, e.g.:
-//   Closure* nothing = NewCallback(&DoNothing);
-void PROTOBUF_EXPORT DoNothing();
-
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_CALLBACK_H_
diff --git a/include/google/protobuf/stubs/casts.h b/include/google/protobuf/stubs/casts.h
deleted file mode 100644
index ad29dac1f8..0000000000
--- a/include/google/protobuf/stubs/casts.h
+++ /dev/null
@@ -1,138 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2014 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_CASTS_H__
-#define GOOGLE_PROTOBUF_CASTS_H__
-
-#include <google/protobuf/stubs/common.h>
-
-#include <google/protobuf/port_def.inc>
-#include <type_traits>
-
-namespace google {
-namespace protobuf {
-namespace internal {
-
-// Use implicit_cast as a safe version of static_cast or const_cast
-// for upcasting in the type hierarchy (i.e. casting a pointer to Foo
-// to a pointer to SuperclassOfFoo or casting a pointer to Foo to
-// a const pointer to Foo).
-// When you use implicit_cast, the compiler checks that the cast is safe.
-// Such explicit implicit_casts are necessary in surprisingly many
-// situations where C++ demands an exact type match instead of an
-// argument type convertible to a target type.
-//
-// The From type can be inferred, so the preferred syntax for using
-// implicit_cast is the same as for static_cast etc.:
-//
-//   implicit_cast<ToType>(expr)
-//
-// implicit_cast would have been part of the C++ standard library,
-// but the proposal was submitted too late.  It will probably make
-// its way into the language in the future.
-template<typename To, typename From>
-inline To implicit_cast(From const &f) {
-  return f;
-}
-
-// When you upcast (that is, cast a pointer from type Foo to type
-// SuperclassOfFoo), it's fine to use implicit_cast<>, since upcasts
-// always succeed.  When you downcast (that is, cast a pointer from
-// type Foo to type SubclassOfFoo), static_cast<> isn't safe, because
-// how do you know the pointer is really of type SubclassOfFoo?  It
-// could be a bare Foo, or of type DifferentSubclassOfFoo.  Thus,
-// when you downcast, you should use this macro.  In debug mode, we
-// use dynamic_cast<> to double-check the downcast is legal (we die
-// if it's not).  In normal mode, we do the efficient static_cast<>
-// instead.  Thus, it's important to test in debug mode to make sure
-// the cast is legal!
-//    This is the only place in the code we should use dynamic_cast<>.
-// In particular, you SHOULDN'T be using dynamic_cast<> in order to
-// do RTTI (eg code like this:
-//    if (dynamic_cast<Subclass1>(foo)) HandleASubclass1Object(foo);
-//    if (dynamic_cast<Subclass2>(foo)) HandleASubclass2Object(foo);
-// You should design the code some other way not to need this.
-
-template<typename To, typename From>     // use like this: down_cast<T*>(foo);
-inline To down_cast(From* f) {                   // so we only accept pointers
-  // Ensures that To is a sub-type of From *.  This test is here only
-  // for compile-time type checking, and has no overhead in an
-  // optimized build at run-time, as it will be optimized away
-  // completely.
-  if (false) {
-    implicit_cast<From*, To>(0);
-  }
-
-#if !defined(NDEBUG) && PROTOBUF_RTTI
-  assert(f == nullptr || dynamic_cast<To>(f) != nullptr);  // RTTI: debug mode only!
-#endif
-  return static_cast<To>(f);
-}
-
-template<typename To, typename From>    // use like this: down_cast<T&>(foo);
-inline To down_cast(From& f) {
-  typedef typename std::remove_reference<To>::type* ToAsPointer;
-  // Ensures that To is a sub-type of From *.  This test is here only
-  // for compile-time type checking, and has no overhead in an
-  // optimized build at run-time, as it will be optimized away
-  // completely.
-  if (false) {
-    implicit_cast<From*, ToAsPointer>(0);
-  }
-
-#if !defined(NDEBUG) && PROTOBUF_RTTI
-  // RTTI: debug mode only!
-  assert(dynamic_cast<ToAsPointer>(&f) != nullptr);
-#endif
-  return *static_cast<ToAsPointer>(&f);
-}
-
-template<typename To, typename From>
-inline To bit_cast(const From& from) {
-  static_assert(sizeof(From) == sizeof(To), "bit_cast_with_different_sizes");
-  To dest;
-  memcpy(&dest, &from, sizeof(dest));
-  return dest;
-}
-
-}  // namespace internal
-
-// We made these internal so that they would show up as such in the docs,
-// but we don't want to stick "internal::" in front of them everywhere.
-using internal::implicit_cast;
-using internal::down_cast;
-using internal::bit_cast;
-
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_CASTS_H__
diff --git a/include/google/protobuf/stubs/common.h b/include/google/protobuf/stubs/common.h
deleted file mode 100644
index c4d26369a3..0000000000
--- a/include/google/protobuf/stubs/common.h
+++ /dev/null
@@ -1,197 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// Author: kenton@google.com (Kenton Varda) and others
-//
-// Contains basic types and utilities used by the rest of the library.
-
-#ifndef GOOGLE_PROTOBUF_COMMON_H__
-#define GOOGLE_PROTOBUF_COMMON_H__
-
-#include <algorithm>
-#include <iostream>
-#include <map>
-#include <memory>
-#include <set>
-#include <string>
-#include <vector>
-
-#include <google/protobuf/stubs/macros.h>
-#include <google/protobuf/stubs/platform_macros.h>
-#include <google/protobuf/stubs/port.h>
-#include <google/protobuf/stubs/stringpiece.h>
-
-#ifndef PROTOBUF_USE_EXCEPTIONS
-#if defined(_MSC_VER) && defined(_CPPUNWIND)
-  #define PROTOBUF_USE_EXCEPTIONS 1
-#elif defined(__EXCEPTIONS)
-  #define PROTOBUF_USE_EXCEPTIONS 1
-#else
-  #define PROTOBUF_USE_EXCEPTIONS 0
-#endif
-#endif
-
-#if PROTOBUF_USE_EXCEPTIONS
-#include <exception>
-#endif
-#if defined(__APPLE__)
-#include <TargetConditionals.h>  // for TARGET_OS_IPHONE
-#endif
-
-#if defined(__ANDROID__) || defined(GOOGLE_PROTOBUF_OS_ANDROID) || (defined(TARGET_OS_IPHONE) && TARGET_OS_IPHONE) || defined(GOOGLE_PROTOBUF_OS_IPHONE)
-#include <pthread.h>
-#endif
-
-#include <google/protobuf/port_def.inc>
-
-namespace std {}
-
-namespace google {
-namespace protobuf {
-namespace internal {
-
-// Some of these constants are macros rather than const ints so that they can
-// be used in #if directives.
-
-// The current version, represented as a single integer to make comparison
-// easier:  major * 10^6 + minor * 10^3 + micro
-#define GOOGLE_PROTOBUF_VERSION 3021004
-
-// A suffix string for alpha, beta or rc releases. Empty for stable releases.
-#define GOOGLE_PROTOBUF_VERSION_SUFFIX ""
-
-// The minimum header version which works with the current version of
-// the library.  This constant should only be used by protoc's C++ code
-// generator.
-static const int kMinHeaderVersionForLibrary = 3021000;
-
-// The minimum protoc version which works with the current version of the
-// headers.
-#define GOOGLE_PROTOBUF_MIN_PROTOC_VERSION 3021000
-
-// The minimum header version which works with the current version of
-// protoc.  This constant should only be used in VerifyVersion().
-static const int kMinHeaderVersionForProtoc = 3021000;
-
-// Verifies that the headers and libraries are compatible.  Use the macro
-// below to call this.
-void PROTOBUF_EXPORT VerifyVersion(int headerVersion, int minLibraryVersion,
-                                   const char* filename);
-
-// Converts a numeric version number to a string.
-std::string PROTOBUF_EXPORT VersionString(int version);
-
-}  // namespace internal
-
-// Place this macro in your main() function (or somewhere before you attempt
-// to use the protobuf library) to verify that the version you link against
-// matches the headers you compiled against.  If a version mismatch is
-// detected, the process will abort.
-#define GOOGLE_PROTOBUF_VERIFY_VERSION                                    \
-  ::google::protobuf::internal::VerifyVersion(                            \
-    GOOGLE_PROTOBUF_VERSION, GOOGLE_PROTOBUF_MIN_LIBRARY_VERSION,         \
-    __FILE__)
-
-
-// ===================================================================
-// from google3/util/utf8/public/unilib.h
-
-namespace internal {
-
-// Checks if the buffer contains structurally-valid UTF-8.  Implemented in
-// structurally_valid.cc.
-PROTOBUF_EXPORT bool IsStructurallyValidUTF8(const char* buf, int len);
-
-inline bool IsStructurallyValidUTF8(StringPiece str) {
-  return IsStructurallyValidUTF8(str.data(), static_cast<int>(str.length()));
-}
-
-// Returns initial number of bytes of structurally valid UTF-8.
-PROTOBUF_EXPORT int UTF8SpnStructurallyValid(StringPiece str);
-
-// Coerce UTF-8 byte string in src_str to be
-// a structurally-valid equal-length string by selectively
-// overwriting illegal bytes with replace_char (typically ' ' or '?').
-// replace_char must be legal printable 7-bit Ascii 0x20..0x7e.
-// src_str is read-only.
-//
-// Returns pointer to output buffer, src_str.data() if no changes were made,
-//  or idst if some bytes were changed. idst is allocated by the caller
-//  and must be at least as big as src_str
-//
-// Optimized for: all structurally valid and no byte copying is done.
-//
-PROTOBUF_EXPORT char* UTF8CoerceToStructurallyValid(StringPiece str, char* dst,
-                                                    char replace_char);
-
-}  // namespace internal
-
-// This lives in message_lite.h now, but we leave this here for any users that
-// #include common.h and not message_lite.h.
-PROTOBUF_EXPORT void ShutdownProtobufLibrary();
-
-namespace internal {
-
-// Strongly references the given variable such that the linker will be forced
-// to pull in this variable's translation unit.
-template <typename T>
-void StrongReference(const T& var) {
-  auto volatile unused = &var;
-  (void)&unused;  // Use address to avoid an extra load of "unused".
-}
-
-}  // namespace internal
-
-#if PROTOBUF_USE_EXCEPTIONS
-class FatalException : public std::exception {
- public:
-  FatalException(const char* filename, int line, const std::string& message)
-      : filename_(filename), line_(line), message_(message) {}
-  virtual ~FatalException() throw();
-
-  const char* what() const throw() override;
-
-  const char* filename() const { return filename_; }
-  int line() const { return line_; }
-  const std::string& message() const { return message_; }
-
- private:
-  const char* filename_;
-  const int line_;
-  const std::string message_;
-};
-#endif
-
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_COMMON_H__
diff --git a/include/google/protobuf/stubs/hash.h b/include/google/protobuf/stubs/hash.h
deleted file mode 100644
index a7ec068074..0000000000
--- a/include/google/protobuf/stubs/hash.h
+++ /dev/null
@@ -1,114 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// Author: kenton@google.com (Kenton Varda)
-
-#ifndef GOOGLE_PROTOBUF_STUBS_HASH_H__
-#define GOOGLE_PROTOBUF_STUBS_HASH_H__
-
-#include <cstring>
-#include <string>
-#include <unordered_map>
-#include <unordered_set>
-
-# define GOOGLE_PROTOBUF_HASH_NAMESPACE_DECLARATION_START \
-  namespace google {                                      \
-  namespace protobuf {
-# define GOOGLE_PROTOBUF_HASH_NAMESPACE_DECLARATION_END }}
-
-namespace google {
-namespace protobuf {
-
-template <typename Key>
-struct hash : public std::hash<Key> {};
-
-template <typename Key>
-struct hash<const Key*> {
-  inline size_t operator()(const Key* key) const {
-    return reinterpret_cast<size_t>(key);
-  }
-};
-
-// Unlike the old SGI version, the TR1 "hash" does not special-case char*.  So,
-// we go ahead and provide our own implementation.
-template <>
-struct hash<const char*> {
-  inline size_t operator()(const char* str) const {
-    size_t result = 0;
-    for (; *str != '\0'; str++) {
-      result = 5 * result + static_cast<size_t>(*str);
-    }
-    return result;
-  }
-};
-
-template<>
-struct hash<bool> {
-  size_t operator()(bool x) const {
-    return static_cast<size_t>(x);
-  }
-};
-
-template <>
-struct hash<std::string> {
-  inline size_t operator()(const std::string& key) const {
-    return hash<const char*>()(key.c_str());
-  }
-
-  static const size_t bucket_size = 4;
-  static const size_t min_buckets = 8;
-  inline bool operator()(const std::string& a, const std::string& b) const {
-    return a < b;
-  }
-};
-
-template <typename First, typename Second>
-struct hash<std::pair<First, Second> > {
-  inline size_t operator()(const std::pair<First, Second>& key) const {
-    size_t first_hash = hash<First>()(key.first);
-    size_t second_hash = hash<Second>()(key.second);
-
-    // FIXME(kenton):  What is the best way to compute this hash?  I have
-    // no idea!  This seems a bit better than an XOR.
-    return first_hash * ((1 << 16) - 1) + second_hash;
-  }
-
-  static const size_t bucket_size = 4;
-  static const size_t min_buckets = 8;
-  inline bool operator()(const std::pair<First, Second>& a,
-                           const std::pair<First, Second>& b) const {
-    return a < b;
-  }
-};
-
-}  // namespace protobuf
-}  // namespace google
-
-#endif  // GOOGLE_PROTOBUF_STUBS_HASH_H__
diff --git a/include/google/protobuf/stubs/logging.h b/include/google/protobuf/stubs/logging.h
deleted file mode 100644
index 8ecc2fa0f1..0000000000
--- a/include/google/protobuf/stubs/logging.h
+++ /dev/null
@@ -1,239 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_STUBS_LOGGING_H_
-#define GOOGLE_PROTOBUF_STUBS_LOGGING_H_
-
-#include <google/protobuf/stubs/macros.h>
-#include <google/protobuf/stubs/port.h>
-#include <google/protobuf/stubs/status.h>
-#include <google/protobuf/stubs/stringpiece.h>
-
-#include <google/protobuf/port_def.inc>
-
-// ===================================================================
-// emulates google3/base/logging.h
-
-namespace google {
-namespace protobuf {
-
-enum LogLevel {
-  LOGLEVEL_INFO,     // Informational.  This is never actually used by
-                     // libprotobuf.
-  LOGLEVEL_WARNING,  // Warns about issues that, although not technically a
-                     // problem now, could cause problems in the future.  For
-                     // example, a // warning will be printed when parsing a
-                     // message that is near the message size limit.
-  LOGLEVEL_ERROR,    // An error occurred which should never happen during
-                     // normal use.
-  LOGLEVEL_FATAL,    // An error occurred from which the library cannot
-                     // recover.  This usually indicates a programming error
-                     // in the code which calls the library, especially when
-                     // compiled in debug mode.
-
-#ifdef NDEBUG
-  LOGLEVEL_DFATAL = LOGLEVEL_ERROR
-#else
-  LOGLEVEL_DFATAL = LOGLEVEL_FATAL
-#endif
-};
-
-class uint128;
-namespace internal {
-
-class LogFinisher;
-
-class PROTOBUF_EXPORT LogMessage {
- public:
-  LogMessage(LogLevel level, const char* filename, int line);
-  ~LogMessage();
-
-  LogMessage& operator<<(const std::string& value);
-  LogMessage& operator<<(const char* value);
-  LogMessage& operator<<(char value);
-  LogMessage& operator<<(int value);
-  LogMessage& operator<<(uint value);
-  LogMessage& operator<<(long value);
-  LogMessage& operator<<(unsigned long value);
-  LogMessage& operator<<(long long value);
-  LogMessage& operator<<(unsigned long long value);
-  LogMessage& operator<<(double value);
-  LogMessage& operator<<(void* value);
-  LogMessage& operator<<(const StringPiece& value);
-  LogMessage& operator<<(const util::Status& status);
-  LogMessage& operator<<(const uint128& value);
-
- private:
-  friend class LogFinisher;
-  void Finish();
-
-  LogLevel level_;
-  const char* filename_;
-  int line_;
-  std::string message_;
-};
-
-// Used to make the entire "LOG(BLAH) << etc." expression have a void return
-// type and print a newline after each message.
-class PROTOBUF_EXPORT LogFinisher {
- public:
-  void operator=(LogMessage& other);
-};
-
-template<typename T>
-bool IsOk(T status) { return status.ok(); }
-template<>
-inline bool IsOk(bool status) { return status; }
-
-}  // namespace internal
-
-// Undef everything in case we're being mixed with some other Google library
-// which already defined them itself.  Presumably all Google libraries will
-// support the same syntax for these so it should not be a big deal if they
-// end up using our definitions instead.
-#undef GOOGLE_LOG
-#undef GOOGLE_LOG_IF
-
-#undef GOOGLE_CHECK
-#undef GOOGLE_CHECK_OK
-#undef GOOGLE_CHECK_EQ
-#undef GOOGLE_CHECK_NE
-#undef GOOGLE_CHECK_LT
-#undef GOOGLE_CHECK_LE
-#undef GOOGLE_CHECK_GT
-#undef GOOGLE_CHECK_GE
-#undef GOOGLE_CHECK_NOTNULL
-
-#undef GOOGLE_DLOG
-#undef GOOGLE_DCHECK
-#undef GOOGLE_DCHECK_OK
-#undef GOOGLE_DCHECK_EQ
-#undef GOOGLE_DCHECK_NE
-#undef GOOGLE_DCHECK_LT
-#undef GOOGLE_DCHECK_LE
-#undef GOOGLE_DCHECK_GT
-#undef GOOGLE_DCHECK_GE
-
-#define GOOGLE_LOG(LEVEL)                          \
-  ::google::protobuf::internal::LogFinisher() = \
-      ::google::protobuf::internal::LogMessage( \
-          ::google::protobuf::LOGLEVEL_##LEVEL, __FILE__, __LINE__)
-#define GOOGLE_LOG_IF(LEVEL, CONDITION) \
-  !(CONDITION) ? (void)0 : GOOGLE_LOG(LEVEL)
-
-#define GOOGLE_CHECK(EXPRESSION) \
-  GOOGLE_LOG_IF(FATAL, !(EXPRESSION)) << "CHECK failed: " #EXPRESSION ": "
-#define GOOGLE_CHECK_OK(A) GOOGLE_CHECK(::google::protobuf::internal::IsOk(A))
-#define GOOGLE_CHECK_EQ(A, B) GOOGLE_CHECK((A) == (B))
-#define GOOGLE_CHECK_NE(A, B) GOOGLE_CHECK((A) != (B))
-#define GOOGLE_CHECK_LT(A, B) GOOGLE_CHECK((A) <  (B))
-#define GOOGLE_CHECK_LE(A, B) GOOGLE_CHECK((A) <= (B))
-#define GOOGLE_CHECK_GT(A, B) GOOGLE_CHECK((A) >  (B))
-#define GOOGLE_CHECK_GE(A, B) GOOGLE_CHECK((A) >= (B))
-
-namespace internal {
-template<typename T>
-T* CheckNotNull(const char* /* file */, int /* line */,
-                const char* name, T* val) {
-  if (val == nullptr) {
-    GOOGLE_LOG(FATAL) << name;
-  }
-  return val;
-}
-}  // namespace internal
-#define GOOGLE_CHECK_NOTNULL(A)               \
-  ::google::protobuf::internal::CheckNotNull( \
-      __FILE__, __LINE__, "'" #A "' must not be nullptr", (A))
-
-#ifdef NDEBUG
-
-#define GOOGLE_DLOG(LEVEL) GOOGLE_LOG_IF(LEVEL, false)
-
-#define GOOGLE_DCHECK(EXPRESSION) while(false) GOOGLE_CHECK(EXPRESSION)
-#define GOOGLE_DCHECK_OK(E) GOOGLE_DCHECK(::google::protobuf::internal::IsOk(E))
-#define GOOGLE_DCHECK_EQ(A, B) GOOGLE_DCHECK((A) == (B))
-#define GOOGLE_DCHECK_NE(A, B) GOOGLE_DCHECK((A) != (B))
-#define GOOGLE_DCHECK_LT(A, B) GOOGLE_DCHECK((A) <  (B))
-#define GOOGLE_DCHECK_LE(A, B) GOOGLE_DCHECK((A) <= (B))
-#define GOOGLE_DCHECK_GT(A, B) GOOGLE_DCHECK((A) >  (B))
-#define GOOGLE_DCHECK_GE(A, B) GOOGLE_DCHECK((A) >= (B))
-
-#else  // NDEBUG
-
-#define GOOGLE_DLOG GOOGLE_LOG
-
-#define GOOGLE_DCHECK    GOOGLE_CHECK
-#define GOOGLE_DCHECK_OK GOOGLE_CHECK_OK
-#define GOOGLE_DCHECK_EQ GOOGLE_CHECK_EQ
-#define GOOGLE_DCHECK_NE GOOGLE_CHECK_NE
-#define GOOGLE_DCHECK_LT GOOGLE_CHECK_LT
-#define GOOGLE_DCHECK_LE GOOGLE_CHECK_LE
-#define GOOGLE_DCHECK_GT GOOGLE_CHECK_GT
-#define GOOGLE_DCHECK_GE GOOGLE_CHECK_GE
-
-#endif  // !NDEBUG
-
-typedef void LogHandler(LogLevel level, const char* filename, int line,
-                        const std::string& message);
-
-// The protobuf library sometimes writes warning and error messages to
-// stderr.  These messages are primarily useful for developers, but may
-// also help end users figure out a problem.  If you would prefer that
-// these messages be sent somewhere other than stderr, call SetLogHandler()
-// to set your own handler.  This returns the old handler.  Set the handler
-// to nullptr to ignore log messages (but see also LogSilencer, below).
-//
-// Obviously, SetLogHandler is not thread-safe.  You should only call it
-// at initialization time, and probably not from library code.  If you
-// simply want to suppress log messages temporarily (e.g. because you
-// have some code that tends to trigger them frequently and you know
-// the warnings are not important to you), use the LogSilencer class
-// below.
-PROTOBUF_EXPORT LogHandler* SetLogHandler(LogHandler* new_func);
-
-// Create a LogSilencer if you want to temporarily suppress all log
-// messages.  As long as any LogSilencer objects exist, non-fatal
-// log messages will be discarded (the current LogHandler will *not*
-// be called).  Constructing a LogSilencer is thread-safe.  You may
-// accidentally suppress log messages occurring in another thread, but
-// since messages are generally for debugging purposes only, this isn't
-// a big deal.  If you want to intercept log messages, use SetLogHandler().
-class PROTOBUF_EXPORT LogSilencer {
- public:
-  LogSilencer();
-  ~LogSilencer();
-};
-
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_LOGGING_H_
diff --git a/include/google/protobuf/stubs/macros.h b/include/google/protobuf/stubs/macros.h
deleted file mode 100644
index ae9a8b987f..0000000000
--- a/include/google/protobuf/stubs/macros.h
+++ /dev/null
@@ -1,93 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_MACROS_H__
-#define GOOGLE_PROTOBUF_MACROS_H__
-
-namespace google {
-namespace protobuf {
-
-#undef GOOGLE_DISALLOW_EVIL_CONSTRUCTORS
-#define GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(TypeName) \
-  TypeName(const TypeName&) = delete;               \
-  void operator=(const TypeName&) = delete
-
-#undef GOOGLE_DISALLOW_IMPLICIT_CONSTRUCTORS
-#define GOOGLE_DISALLOW_IMPLICIT_CONSTRUCTORS(TypeName) \
-  TypeName() = delete;                                  \
-  TypeName(const TypeName&) = delete;                   \
-  void operator=(const TypeName&) = delete
-
-// ===================================================================
-// from google3/base/basictypes.h
-
-// The GOOGLE_ARRAYSIZE(arr) macro returns the # of elements in an array arr.
-// The expression is a compile-time constant, and therefore can be
-// used in defining new arrays, for example.
-//
-// GOOGLE_ARRAYSIZE catches a few type errors.  If you see a compiler error
-//
-//   "warning: division by zero in ..."
-//
-// when using GOOGLE_ARRAYSIZE, you are (wrongfully) giving it a pointer.
-// You should only use GOOGLE_ARRAYSIZE on statically allocated arrays.
-//
-// The following comments are on the implementation details, and can
-// be ignored by the users.
-//
-// ARRAYSIZE(arr) works by inspecting sizeof(arr) (the # of bytes in
-// the array) and sizeof(*(arr)) (the # of bytes in one array
-// element).  If the former is divisible by the latter, perhaps arr is
-// indeed an array, in which case the division result is the # of
-// elements in the array.  Otherwise, arr cannot possibly be an array,
-// and we generate a compiler error to prevent the code from
-// compiling.
-//
-// Since the size of bool is implementation-defined, we need to cast
-// !(sizeof(a) & sizeof(*(a))) to size_t in order to ensure the final
-// result has type size_t.
-//
-// This macro is not perfect as it wrongfully accepts certain
-// pointers, namely where the pointer size is divisible by the pointee
-// size.  Since all our code has to go through a 32-bit compiler,
-// where a pointer is 4 bytes, this means all pointers to a type whose
-// size is 3 or greater than 4 will be (righteously) rejected.
-//
-// Kudos to Jorg Brown for this simple and elegant implementation.
-
-#undef GOOGLE_ARRAYSIZE
-#define GOOGLE_ARRAYSIZE(a) \
-  ((sizeof(a) / sizeof(*(a))) / \
-   static_cast<size_t>(!(sizeof(a) % sizeof(*(a)))))
-
-}  // namespace protobuf
-}  // namespace google
-
-#endif  // GOOGLE_PROTOBUF_MACROS_H__
diff --git a/include/google/protobuf/stubs/map_util.h b/include/google/protobuf/stubs/map_util.h
deleted file mode 100644
index 24e098ad1b..0000000000
--- a/include/google/protobuf/stubs/map_util.h
+++ /dev/null
@@ -1,769 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2014 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// from google3/util/gtl/map_util.h
-// Author: Anton Carver
-
-#ifndef GOOGLE_PROTOBUF_STUBS_MAP_UTIL_H__
-#define GOOGLE_PROTOBUF_STUBS_MAP_UTIL_H__
-
-#include <stddef.h>
-#include <iterator>
-#include <string>
-#include <utility>
-#include <vector>
-
-#include <google/protobuf/stubs/common.h>
-
-namespace google {
-namespace protobuf {
-namespace internal {
-// Local implementation of RemoveConst to avoid including base/type_traits.h.
-template <class T> struct RemoveConst { typedef T type; };
-template <class T> struct RemoveConst<const T> : RemoveConst<T> {};
-}  // namespace internal
-
-//
-// Find*()
-//
-
-// Returns a const reference to the value associated with the given key if it
-// exists. Crashes otherwise.
-//
-// This is intended as a replacement for operator[] as an rvalue (for reading)
-// when the key is guaranteed to exist.
-//
-// operator[] for lookup is discouraged for several reasons:
-//  * It has a side-effect of inserting missing keys
-//  * It is not thread-safe (even when it is not inserting, it can still
-//      choose to resize the underlying storage)
-//  * It invalidates iterators (when it chooses to resize)
-//  * It default constructs a value object even if it doesn't need to
-//
-// This version assumes the key is printable, and includes it in the fatal log
-// message.
-template <class Collection>
-const typename Collection::value_type::second_type&
-FindOrDie(const Collection& collection,
-          const typename Collection::value_type::first_type& key) {
-  typename Collection::const_iterator it = collection.find(key);
-  GOOGLE_CHECK(it != collection.end()) << "Map key not found: " << key;
-  return it->second;
-}
-
-// Same as above, but returns a non-const reference.
-template <class Collection>
-typename Collection::value_type::second_type&
-FindOrDie(Collection& collection,  // NOLINT
-          const typename Collection::value_type::first_type& key) {
-  typename Collection::iterator it = collection.find(key);
-  GOOGLE_CHECK(it != collection.end()) << "Map key not found: " << key;
-  return it->second;
-}
-
-// Same as FindOrDie above, but doesn't log the key on failure.
-template <class Collection>
-const typename Collection::value_type::second_type&
-FindOrDieNoPrint(const Collection& collection,
-                 const typename Collection::value_type::first_type& key) {
-  typename Collection::const_iterator it = collection.find(key);
-  GOOGLE_CHECK(it != collection.end()) << "Map key not found";
-  return it->second;
-}
-
-// Same as above, but returns a non-const reference.
-template <class Collection>
-typename Collection::value_type::second_type&
-FindOrDieNoPrint(Collection& collection,  // NOLINT
-                 const typename Collection::value_type::first_type& key) {
-  typename Collection::iterator it = collection.find(key);
-  GOOGLE_CHECK(it != collection.end()) << "Map key not found";
-  return it->second;
-}
-
-// Returns a const reference to the value associated with the given key if it
-// exists, otherwise returns a const reference to the provided default value.
-//
-// WARNING: If a temporary object is passed as the default "value,"
-// this function will return a reference to that temporary object,
-// which will be destroyed at the end of the statement. A common
-// example: if you have a map with string values, and you pass a char*
-// as the default "value," either use the returned value immediately
-// or store it in a string (not string&).
-// Details: http://go/findwithdefault
-template <class Collection>
-const typename Collection::value_type::second_type&
-FindWithDefault(const Collection& collection,
-                const typename Collection::value_type::first_type& key,
-                const typename Collection::value_type::second_type& value) {
-  typename Collection::const_iterator it = collection.find(key);
-  if (it == collection.end()) {
-    return value;
-  }
-  return it->second;
-}
-
-// Returns a pointer to the const value associated with the given key if it
-// exists, or nullptr otherwise.
-template <class Collection>
-const typename Collection::value_type::second_type*
-FindOrNull(const Collection& collection,
-           const typename Collection::value_type::first_type& key) {
-  typename Collection::const_iterator it = collection.find(key);
-  if (it == collection.end()) {
-    return 0;
-  }
-  return &it->second;
-}
-
-// Same as above but returns a pointer to the non-const value.
-template <class Collection>
-typename Collection::value_type::second_type*
-FindOrNull(Collection& collection,  // NOLINT
-           const typename Collection::value_type::first_type& key) {
-  typename Collection::iterator it = collection.find(key);
-  if (it == collection.end()) {
-    return 0;
-  }
-  return &it->second;
-}
-
-// Returns the pointer value associated with the given key. If none is found,
-// nullptr is returned. The function is designed to be used with a map of keys to
-// pointers.
-//
-// This function does not distinguish between a missing key and a key mapped
-// to nullptr.
-template <class Collection>
-typename Collection::value_type::second_type
-FindPtrOrNull(const Collection& collection,
-              const typename Collection::value_type::first_type& key) {
-  typename Collection::const_iterator it = collection.find(key);
-  if (it == collection.end()) {
-    return typename Collection::value_type::second_type();
-  }
-  return it->second;
-}
-
-// Same as above, except takes non-const reference to collection.
-//
-// This function is needed for containers that propagate constness to the
-// pointee, such as boost::ptr_map.
-template <class Collection>
-typename Collection::value_type::second_type
-FindPtrOrNull(Collection& collection,  // NOLINT
-              const typename Collection::value_type::first_type& key) {
-  typename Collection::iterator it = collection.find(key);
-  if (it == collection.end()) {
-    return typename Collection::value_type::second_type();
-  }
-  return it->second;
-}
-
-// Finds the pointer value associated with the given key in a map whose values
-// are linked_ptrs. Returns nullptr if key is not found.
-template <class Collection>
-typename Collection::value_type::second_type::element_type*
-FindLinkedPtrOrNull(const Collection& collection,
-                    const typename Collection::value_type::first_type& key) {
-  typename Collection::const_iterator it = collection.find(key);
-  if (it == collection.end()) {
-    return 0;
-  }
-  // Since linked_ptr::get() is a const member returning a non const,
-  // we do not need a version of this function taking a non const collection.
-  return it->second.get();
-}
-
-// Same as above, but dies if the key is not found.
-template <class Collection>
-typename Collection::value_type::second_type::element_type&
-FindLinkedPtrOrDie(const Collection& collection,
-                   const typename Collection::value_type::first_type& key) {
-  typename Collection::const_iterator it = collection.find(key);
-  GOOGLE_CHECK(it != collection.end()) <<  "key not found: " << key;
-  // Since linked_ptr::operator*() is a const member returning a non const,
-  // we do not need a version of this function taking a non const collection.
-  return *it->second;
-}
-
-// Finds the value associated with the given key and copies it to *value (if not
-// nullptr). Returns false if the key was not found, true otherwise.
-template <class Collection, class Key, class Value>
-bool FindCopy(const Collection& collection,
-              const Key& key,
-              Value* const value) {
-  typename Collection::const_iterator it = collection.find(key);
-  if (it == collection.end()) {
-    return false;
-  }
-  if (value) {
-    *value = it->second;
-  }
-  return true;
-}
-
-//
-// Contains*()
-//
-
-// Returns true if and only if the given collection contains the given key.
-template <class Collection, class Key>
-bool ContainsKey(const Collection& collection, const Key& key) {
-  return collection.find(key) != collection.end();
-}
-
-// Returns true if and only if the given collection contains the given key-value
-// pair.
-template <class Collection, class Key, class Value>
-bool ContainsKeyValuePair(const Collection& collection,
-                          const Key& key,
-                          const Value& value) {
-  typedef typename Collection::const_iterator const_iterator;
-  std::pair<const_iterator, const_iterator> range = collection.equal_range(key);
-  for (const_iterator it = range.first; it != range.second; ++it) {
-    if (it->second == value) {
-      return true;
-    }
-  }
-  return false;
-}
-
-//
-// Insert*()
-//
-
-// Inserts the given key-value pair into the collection. Returns true if and
-// only if the key from the given pair didn't previously exist. Otherwise, the
-// value in the map is replaced with the value from the given pair.
-template <class Collection>
-bool InsertOrUpdate(Collection* const collection,
-                    const typename Collection::value_type& vt) {
-  std::pair<typename Collection::iterator, bool> ret = collection->insert(vt);
-  if (!ret.second) {
-    // update
-    ret.first->second = vt.second;
-    return false;
-  }
-  return true;
-}
-
-// Same as above, except that the key and value are passed separately.
-template <class Collection>
-bool InsertOrUpdate(Collection* const collection,
-                    const typename Collection::value_type::first_type& key,
-                    const typename Collection::value_type::second_type& value) {
-  return InsertOrUpdate(
-      collection, typename Collection::value_type(key, value));
-}
-
-// Inserts/updates all the key-value pairs from the range defined by the
-// iterators "first" and "last" into the given collection.
-template <class Collection, class InputIterator>
-void InsertOrUpdateMany(Collection* const collection,
-                        InputIterator first, InputIterator last) {
-  for (; first != last; ++first) {
-    InsertOrUpdate(collection, *first);
-  }
-}
-
-// Change the value associated with a particular key in a map or hash_map
-// of the form map<Key, Value*> which owns the objects pointed to by the
-// value pointers.  If there was an existing value for the key, it is deleted.
-// True indicates an insert took place, false indicates an update + delete.
-template <class Collection>
-bool InsertAndDeleteExisting(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key,
-    const typename Collection::value_type::second_type& value) {
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(key, value));
-  if (!ret.second) {
-    delete ret.first->second;
-    ret.first->second = value;
-    return false;
-  }
-  return true;
-}
-
-// Inserts the given key and value into the given collection if and only if the
-// given key did NOT already exist in the collection. If the key previously
-// existed in the collection, the value is not changed. Returns true if the
-// key-value pair was inserted; returns false if the key was already present.
-template <class Collection>
-bool InsertIfNotPresent(Collection* const collection,
-                        const typename Collection::value_type& vt) {
-  return collection->insert(vt).second;
-}
-
-// Same as above except the key and value are passed separately.
-template <class Collection>
-bool InsertIfNotPresent(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key,
-    const typename Collection::value_type::second_type& value) {
-  return InsertIfNotPresent(
-      collection, typename Collection::value_type(key, value));
-}
-
-// Same as above except dies if the key already exists in the collection.
-template <class Collection>
-void InsertOrDie(Collection* const collection,
-                 const typename Collection::value_type& value) {
-  GOOGLE_CHECK(InsertIfNotPresent(collection, value))
-      << "duplicate value: " << value;
-}
-
-// Same as above except doesn't log the value on error.
-template <class Collection>
-void InsertOrDieNoPrint(Collection* const collection,
-                        const typename Collection::value_type& value) {
-  GOOGLE_CHECK(InsertIfNotPresent(collection, value)) << "duplicate value.";
-}
-
-// Inserts the key-value pair into the collection. Dies if key was already
-// present.
-template <class Collection>
-void InsertOrDie(Collection* const collection,
-                 const typename Collection::value_type::first_type& key,
-                 const typename Collection::value_type::second_type& data) {
-  GOOGLE_CHECK(InsertIfNotPresent(collection, key, data))
-      << "duplicate key: " << key;
-}
-
-// Same as above except doesn't log the key on error.
-template <class Collection>
-void InsertOrDieNoPrint(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key,
-    const typename Collection::value_type::second_type& data) {
-  GOOGLE_CHECK(InsertIfNotPresent(collection, key, data)) << "duplicate key.";
-}
-
-// Inserts a new key and default-initialized value. Dies if the key was already
-// present. Returns a reference to the value. Example usage:
-//
-// map<int, SomeProto> m;
-// SomeProto& proto = InsertKeyOrDie(&m, 3);
-// proto.set_field("foo");
-template <class Collection>
-typename Collection::value_type::second_type& InsertKeyOrDie(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key) {
-  typedef typename Collection::value_type value_type;
-  std::pair<typename Collection::iterator, bool> res =
-      collection->insert(value_type(key, typename value_type::second_type()));
-  GOOGLE_CHECK(res.second) << "duplicate key: " << key;
-  return res.first->second;
-}
-
-//
-// Lookup*()
-//
-
-// Looks up a given key and value pair in a collection and inserts the key-value
-// pair if it's not already present. Returns a reference to the value associated
-// with the key.
-template <class Collection>
-typename Collection::value_type::second_type&
-LookupOrInsert(Collection* const collection,
-               const typename Collection::value_type& vt) {
-  return collection->insert(vt).first->second;
-}
-
-// Same as above except the key-value are passed separately.
-template <class Collection>
-typename Collection::value_type::second_type&
-LookupOrInsert(Collection* const collection,
-               const typename Collection::value_type::first_type& key,
-               const typename Collection::value_type::second_type& value) {
-  return LookupOrInsert(
-      collection, typename Collection::value_type(key, value));
-}
-
-// Counts the number of equivalent elements in the given "sequence", and stores
-// the results in "count_map" with element as the key and count as the value.
-//
-// Example:
-//   vector<string> v = {"a", "b", "c", "a", "b"};
-//   map<string, int> m;
-//   AddTokenCounts(v, 1, &m);
-//   assert(m["a"] == 2);
-//   assert(m["b"] == 2);
-//   assert(m["c"] == 1);
-template <typename Sequence, typename Collection>
-void AddTokenCounts(
-    const Sequence& sequence,
-    const typename Collection::value_type::second_type& increment,
-    Collection* const count_map) {
-  for (typename Sequence::const_iterator it = sequence.begin();
-       it != sequence.end(); ++it) {
-    typename Collection::value_type::second_type& value =
-        LookupOrInsert(count_map, *it,
-                       typename Collection::value_type::second_type());
-    value += increment;
-  }
-}
-
-// Returns a reference to the value associated with key. If not found, a value
-// is default constructed on the heap and added to the map.
-//
-// This function is useful for containers of the form map<Key, Value*>, where
-// inserting a new key, value pair involves constructing a new heap-allocated
-// Value, and storing a pointer to that in the collection.
-template <class Collection>
-typename Collection::value_type::second_type&
-LookupOrInsertNew(Collection* const collection,
-                  const typename Collection::value_type::first_type& key) {
-  typedef typename std::iterator_traits<
-    typename Collection::value_type::second_type>::value_type Element;
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(
-          key,
-          static_cast<typename Collection::value_type::second_type>(nullptr)));
-  if (ret.second) {
-    ret.first->second = new Element();
-  }
-  return ret.first->second;
-}
-
-// Same as above but constructs the value using the single-argument constructor
-// and the given "arg".
-template <class Collection, class Arg>
-typename Collection::value_type::second_type&
-LookupOrInsertNew(Collection* const collection,
-                  const typename Collection::value_type::first_type& key,
-                  const Arg& arg) {
-  typedef typename std::iterator_traits<
-    typename Collection::value_type::second_type>::value_type Element;
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(
-          key,
-          static_cast<typename Collection::value_type::second_type>(nullptr)));
-  if (ret.second) {
-    ret.first->second = new Element(arg);
-  }
-  return ret.first->second;
-}
-
-// Lookup of linked/shared pointers is used in two scenarios:
-//
-// Use LookupOrInsertNewLinkedPtr if the container owns the elements.
-// In this case it is fine working with the raw pointer as long as it is
-// guaranteed that no other thread can delete/update an accessed element.
-// A mutex will need to lock the container operation as well as the use
-// of the returned elements. Finding an element may be performed using
-// FindLinkedPtr*().
-//
-// Use LookupOrInsertNewSharedPtr if the container does not own the elements
-// for their whole lifetime. This is typically the case when a reader allows
-// parallel updates to the container. In this case a Mutex only needs to lock
-// container operations, but all element operations must be performed on the
-// shared pointer. Finding an element must be performed using FindPtr*() and
-// cannot be done with FindLinkedPtr*() even though it compiles.
-
-// Lookup a key in a map or hash_map whose values are linked_ptrs.  If it is
-// missing, set collection[key].reset(new Value::element_type) and return that.
-// Value::element_type must be default constructable.
-template <class Collection>
-typename Collection::value_type::second_type::element_type*
-LookupOrInsertNewLinkedPtr(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key) {
-  typedef typename Collection::value_type::second_type Value;
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(key, Value()));
-  if (ret.second) {
-    ret.first->second.reset(new typename Value::element_type);
-  }
-  return ret.first->second.get();
-}
-
-// A variant of LookupOrInsertNewLinkedPtr where the value is constructed using
-// a single-parameter constructor.  Note: the constructor argument is computed
-// even if it will not be used, so only values cheap to compute should be passed
-// here.  On the other hand it does not matter how expensive the construction of
-// the actual stored value is, as that only occurs if necessary.
-template <class Collection, class Arg>
-typename Collection::value_type::second_type::element_type*
-LookupOrInsertNewLinkedPtr(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key,
-    const Arg& arg) {
-  typedef typename Collection::value_type::second_type Value;
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(key, Value()));
-  if (ret.second) {
-    ret.first->second.reset(new typename Value::element_type(arg));
-  }
-  return ret.first->second.get();
-}
-
-// Lookup a key in a map or hash_map whose values are shared_ptrs.  If it is
-// missing, set collection[key].reset(new Value::element_type). Unlike
-// LookupOrInsertNewLinkedPtr, this function returns the shared_ptr instead of
-// the raw pointer. Value::element_type must be default constructable.
-template <class Collection>
-typename Collection::value_type::second_type&
-LookupOrInsertNewSharedPtr(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key) {
-  typedef typename Collection::value_type::second_type SharedPtr;
-  typedef typename Collection::value_type::second_type::element_type Element;
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(key, SharedPtr()));
-  if (ret.second) {
-    ret.first->second.reset(new Element());
-  }
-  return ret.first->second;
-}
-
-// A variant of LookupOrInsertNewSharedPtr where the value is constructed using
-// a single-parameter constructor.  Note: the constructor argument is computed
-// even if it will not be used, so only values cheap to compute should be passed
-// here.  On the other hand it does not matter how expensive the construction of
-// the actual stored value is, as that only occurs if necessary.
-template <class Collection, class Arg>
-typename Collection::value_type::second_type&
-LookupOrInsertNewSharedPtr(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key,
-    const Arg& arg) {
-  typedef typename Collection::value_type::second_type SharedPtr;
-  typedef typename Collection::value_type::second_type::element_type Element;
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(key, SharedPtr()));
-  if (ret.second) {
-    ret.first->second.reset(new Element(arg));
-  }
-  return ret.first->second;
-}
-
-//
-// Misc Utility Functions
-//
-
-// Updates the value associated with the given key. If the key was not already
-// present, then the key-value pair are inserted and "previous" is unchanged. If
-// the key was already present, the value is updated and "*previous" will
-// contain a copy of the old value.
-//
-// InsertOrReturnExisting has complementary behavior that returns the
-// address of an already existing value, rather than updating it.
-template <class Collection>
-bool UpdateReturnCopy(Collection* const collection,
-                      const typename Collection::value_type::first_type& key,
-                      const typename Collection::value_type::second_type& value,
-                      typename Collection::value_type::second_type* previous) {
-  std::pair<typename Collection::iterator, bool> ret =
-      collection->insert(typename Collection::value_type(key, value));
-  if (!ret.second) {
-    // update
-    if (previous) {
-      *previous = ret.first->second;
-    }
-    ret.first->second = value;
-    return true;
-  }
-  return false;
-}
-
-// Same as above except that the key and value are passed as a pair.
-template <class Collection>
-bool UpdateReturnCopy(Collection* const collection,
-                      const typename Collection::value_type& vt,
-                      typename Collection::value_type::second_type* previous) {
-  std::pair<typename Collection::iterator, bool> ret = collection->insert(vt);
-  if (!ret.second) {
-    // update
-    if (previous) {
-      *previous = ret.first->second;
-    }
-    ret.first->second = vt.second;
-    return true;
-  }
-  return false;
-}
-
-// Tries to insert the given key-value pair into the collection. Returns nullptr if
-// the insert succeeds. Otherwise, returns a pointer to the existing value.
-//
-// This complements UpdateReturnCopy in that it allows to update only after
-// verifying the old value and still insert quickly without having to look up
-// twice. Unlike UpdateReturnCopy this also does not come with the issue of an
-// undefined previous* in case new data was inserted.
-template <class Collection>
-typename Collection::value_type::second_type* InsertOrReturnExisting(
-    Collection* const collection, const typename Collection::value_type& vt) {
-  std::pair<typename Collection::iterator, bool> ret = collection->insert(vt);
-  if (ret.second) {
-    return nullptr;  // Inserted, no existing previous value.
-  } else {
-    return &ret.first->second;  // Return address of already existing value.
-  }
-}
-
-// Same as above, except for explicit key and data.
-template <class Collection>
-typename Collection::value_type::second_type* InsertOrReturnExisting(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key,
-    const typename Collection::value_type::second_type& data) {
-  return InsertOrReturnExisting(collection,
-                                typename Collection::value_type(key, data));
-}
-
-// Erases the collection item identified by the given key, and returns the value
-// associated with that key. It is assumed that the value (i.e., the
-// mapped_type) is a pointer. Returns nullptr if the key was not found in the
-// collection.
-//
-// Examples:
-//   map<string, MyType*> my_map;
-//
-// One line cleanup:
-//     delete EraseKeyReturnValuePtr(&my_map, "abc");
-//
-// Use returned value:
-//     std::unique_ptr<MyType> value_ptr(
-//         EraseKeyReturnValuePtr(&my_map, "abc"));
-//     if (value_ptr.get())
-//       value_ptr->DoSomething();
-//
-template <class Collection>
-typename Collection::value_type::second_type EraseKeyReturnValuePtr(
-    Collection* const collection,
-    const typename Collection::value_type::first_type& key) {
-  typename Collection::iterator it = collection->find(key);
-  if (it == collection->end()) {
-    return nullptr;
-  }
-  typename Collection::value_type::second_type v = it->second;
-  collection->erase(it);
-  return v;
-}
-
-// Inserts all the keys from map_container into key_container, which must
-// support insert(MapContainer::key_type).
-//
-// Note: any initial contents of the key_container are not cleared.
-template <class MapContainer, class KeyContainer>
-void InsertKeysFromMap(const MapContainer& map_container,
-                       KeyContainer* key_container) {
-  GOOGLE_CHECK(key_container != nullptr);
-  for (typename MapContainer::const_iterator it = map_container.begin();
-       it != map_container.end(); ++it) {
-    key_container->insert(it->first);
-  }
-}
-
-// Appends all the keys from map_container into key_container, which must
-// support push_back(MapContainer::key_type).
-//
-// Note: any initial contents of the key_container are not cleared.
-template <class MapContainer, class KeyContainer>
-void AppendKeysFromMap(const MapContainer& map_container,
-                       KeyContainer* key_container) {
-  GOOGLE_CHECK(key_container != nullptr);
-  for (typename MapContainer::const_iterator it = map_container.begin();
-       it != map_container.end(); ++it) {
-    key_container->push_back(it->first);
-  }
-}
-
-// A more specialized overload of AppendKeysFromMap to optimize reallocations
-// for the common case in which we're appending keys to a vector and hence can
-// (and sometimes should) call reserve() first.
-//
-// (It would be possible to play SFINAE games to call reserve() for any
-// container that supports it, but this seems to get us 99% of what we need
-// without the complexity of a SFINAE-based solution.)
-template <class MapContainer, class KeyType>
-void AppendKeysFromMap(const MapContainer& map_container,
-                       std::vector<KeyType>* key_container) {
-  GOOGLE_CHECK(key_container != nullptr);
-  // We now have the opportunity to call reserve(). Calling reserve() every
-  // time is a bad idea for some use cases: libstdc++'s implementation of
-  // vector<>::reserve() resizes the vector's backing store to exactly the
-  // given size (unless it's already at least that big). Because of this,
-  // the use case that involves appending a lot of small maps (total size
-  // N) one by one to a vector would be O(N^2). But never calling reserve()
-  // loses the opportunity to improve the use case of adding from a large
-  // map to an empty vector (this improves performance by up to 33%). A
-  // number of heuristics are possible; see the discussion in
-  // cl/34081696. Here we use the simplest one.
-  if (key_container->empty()) {
-    key_container->reserve(map_container.size());
-  }
-  for (typename MapContainer::const_iterator it = map_container.begin();
-       it != map_container.end(); ++it) {
-    key_container->push_back(it->first);
-  }
-}
-
-// Inserts all the values from map_container into value_container, which must
-// support push_back(MapContainer::mapped_type).
-//
-// Note: any initial contents of the value_container are not cleared.
-template <class MapContainer, class ValueContainer>
-void AppendValuesFromMap(const MapContainer& map_container,
-                         ValueContainer* value_container) {
-  GOOGLE_CHECK(value_container != nullptr);
-  for (typename MapContainer::const_iterator it = map_container.begin();
-       it != map_container.end(); ++it) {
-    value_container->push_back(it->second);
-  }
-}
-
-// A more specialized overload of AppendValuesFromMap to optimize reallocations
-// for the common case in which we're appending values to a vector and hence
-// can (and sometimes should) call reserve() first.
-//
-// (It would be possible to play SFINAE games to call reserve() for any
-// container that supports it, but this seems to get us 99% of what we need
-// without the complexity of a SFINAE-based solution.)
-template <class MapContainer, class ValueType>
-void AppendValuesFromMap(const MapContainer& map_container,
-                         std::vector<ValueType>* value_container) {
-  GOOGLE_CHECK(value_container != nullptr);
-  // See AppendKeysFromMap for why this is done.
-  if (value_container->empty()) {
-    value_container->reserve(map_container.size());
-  }
-  for (typename MapContainer::const_iterator it = map_container.begin();
-       it != map_container.end(); ++it) {
-    value_container->push_back(it->second);
-  }
-}
-
-}  // namespace protobuf
-}  // namespace google
-
-#endif  // GOOGLE_PROTOBUF_STUBS_MAP_UTIL_H__
diff --git a/include/google/protobuf/stubs/mutex.h b/include/google/protobuf/stubs/mutex.h
deleted file mode 100644
index c4599913be..0000000000
--- a/include/google/protobuf/stubs/mutex.h
+++ /dev/null
@@ -1,218 +0,0 @@
-// Copyright (c) 2006, Google Inc.
-// All rights reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_STUBS_MUTEX_H_
-#define GOOGLE_PROTOBUF_STUBS_MUTEX_H_
-
-#include <mutex>
-
-#ifdef GOOGLE_PROTOBUF_SUPPORT_WINDOWS_XP
-
-#include <windows.h>
-
-// GetMessage conflicts with GeneratedMessageReflection::GetMessage().
-#ifdef GetMessage
-#undef GetMessage
-#endif
-
-#endif
-
-#include <google/protobuf/stubs/macros.h>
-
-// Define thread-safety annotations for use below, if we are building with
-// Clang.
-#if defined(__clang__) && !defined(SWIG)
-#define GOOGLE_PROTOBUF_ACQUIRE(...) \
-  __attribute__((acquire_capability(__VA_ARGS__)))
-#define GOOGLE_PROTOBUF_RELEASE(...) \
-  __attribute__((release_capability(__VA_ARGS__)))
-#define GOOGLE_PROTOBUF_SCOPED_CAPABILITY __attribute__((scoped_lockable))
-#define GOOGLE_PROTOBUF_CAPABILITY(x) __attribute__((capability(x)))
-#else
-#define GOOGLE_PROTOBUF_ACQUIRE(...)
-#define GOOGLE_PROTOBUF_RELEASE(...)
-#define GOOGLE_PROTOBUF_SCOPED_CAPABILITY
-#define GOOGLE_PROTOBUF_CAPABILITY(x)
-#endif
-
-#include <google/protobuf/port_def.inc>
-
-// ===================================================================
-// emulates google3/base/mutex.h
-namespace google {
-namespace protobuf {
-namespace internal {
-
-#define GOOGLE_PROTOBUF_LINKER_INITIALIZED
-
-#ifdef GOOGLE_PROTOBUF_SUPPORT_WINDOWS_XP
-
-// This class is a lightweight replacement for std::mutex on Windows platforms.
-// std::mutex does not work on Windows XP SP2 with the latest VC++ libraries,
-// because it utilizes the Concurrency Runtime that is only supported on Windows
-// XP SP3 and above.
-class PROTOBUF_EXPORT CriticalSectionLock {
- public:
-  CriticalSectionLock() { InitializeCriticalSection(&critical_section_); }
-  ~CriticalSectionLock() { DeleteCriticalSection(&critical_section_); }
-  void lock() { EnterCriticalSection(&critical_section_); }
-  void unlock() { LeaveCriticalSection(&critical_section_); }
-
- private:
-  CRITICAL_SECTION critical_section_;
-
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(CriticalSectionLock);
-};
-
-#endif
-
-// In MSVC std::mutex does not have a constexpr constructor.
-// This wrapper makes the constructor constexpr.
-template <typename T>
-class CallOnceInitializedMutex {
- public:
-  constexpr CallOnceInitializedMutex() : flag_{}, buf_{} {}
-  ~CallOnceInitializedMutex() { get().~T(); }
-
-  void lock() { get().lock(); }
-  void unlock() { get().unlock(); }
-
- private:
-  T& get() {
-    std::call_once(flag_, [&] { ::new (static_cast<void*>(&buf_)) T(); });
-    return reinterpret_cast<T&>(buf_);
-  }
-
-  std::once_flag flag_;
-  alignas(T) char buf_[sizeof(T)];
-};
-
-// Mutex is a natural type to wrap. As both google and other organization have
-// specialized mutexes. gRPC also provides an injection mechanism for custom
-// mutexes.
-class GOOGLE_PROTOBUF_CAPABILITY("mutex") PROTOBUF_EXPORT WrappedMutex {
- public:
-#if defined(__QNX__)
-  constexpr WrappedMutex() = default;
-#else
-  constexpr WrappedMutex() {}
-#endif
-  void Lock() GOOGLE_PROTOBUF_ACQUIRE() { mu_.lock(); }
-  void Unlock() GOOGLE_PROTOBUF_RELEASE() { mu_.unlock(); }
-  // Crash if this Mutex is not held exclusively by this thread.
-  // May fail to crash when it should; will never crash when it should not.
-  void AssertHeld() const {}
-
- private:
-#if defined(GOOGLE_PROTOBUF_SUPPORT_WINDOWS_XP)
-  CallOnceInitializedMutex<CriticalSectionLock> mu_{};
-#elif defined(_WIN32)
-  CallOnceInitializedMutex<std::mutex> mu_{};
-#else
-  std::mutex mu_{};
-#endif
-};
-
-using Mutex = WrappedMutex;
-
-// MutexLock(mu) acquires mu when constructed and releases it when destroyed.
-class GOOGLE_PROTOBUF_SCOPED_CAPABILITY PROTOBUF_EXPORT MutexLock {
- public:
-  explicit MutexLock(Mutex* mu) GOOGLE_PROTOBUF_ACQUIRE(mu) : mu_(mu) {
-    this->mu_->Lock();
-  }
-  ~MutexLock() GOOGLE_PROTOBUF_RELEASE() { this->mu_->Unlock(); }
-
- private:
-  Mutex *const mu_;
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MutexLock);
-};
-
-// TODO(kenton):  Implement these?  Hard to implement portably.
-typedef MutexLock ReaderMutexLock;
-typedef MutexLock WriterMutexLock;
-
-// MutexLockMaybe is like MutexLock, but is a no-op when mu is nullptr.
-class PROTOBUF_EXPORT MutexLockMaybe {
- public:
-  explicit MutexLockMaybe(Mutex *mu) :
-    mu_(mu) { if (this->mu_ != nullptr) { this->mu_->Lock(); } }
-  ~MutexLockMaybe() { if (this->mu_ != nullptr) { this->mu_->Unlock(); } }
- private:
-  Mutex *const mu_;
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(MutexLockMaybe);
-};
-
-#if defined(GOOGLE_PROTOBUF_NO_THREADLOCAL)
-template<typename T>
-class ThreadLocalStorage {
- public:
-  ThreadLocalStorage() {
-    pthread_key_create(&key_, &ThreadLocalStorage::Delete);
-  }
-  ~ThreadLocalStorage() {
-    pthread_key_delete(key_);
-  }
-  T* Get() {
-    T* result = static_cast<T*>(pthread_getspecific(key_));
-    if (result == nullptr) {
-      result = new T();
-      pthread_setspecific(key_, result);
-    }
-    return result;
-  }
- private:
-  static void Delete(void* value) {
-    delete static_cast<T*>(value);
-  }
-  pthread_key_t key_;
-
-  GOOGLE_DISALLOW_EVIL_CONSTRUCTORS(ThreadLocalStorage);
-};
-#endif
-
-}  // namespace internal
-
-// We made these internal so that they would show up as such in the docs,
-// but we don't want to stick "internal::" in front of them everywhere.
-using internal::Mutex;
-using internal::MutexLock;
-using internal::ReaderMutexLock;
-using internal::WriterMutexLock;
-using internal::MutexLockMaybe;
-
-}  // namespace protobuf
-}  // namespace google
-
-#undef GOOGLE_PROTOBUF_ACQUIRE
-#undef GOOGLE_PROTOBUF_RELEASE
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_MUTEX_H_
diff --git a/include/google/protobuf/stubs/once.h b/include/google/protobuf/stubs/once.h
deleted file mode 100644
index 070d36d193..0000000000
--- a/include/google/protobuf/stubs/once.h
+++ /dev/null
@@ -1,55 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_STUBS_ONCE_H__
-#define GOOGLE_PROTOBUF_STUBS_ONCE_H__
-
-#include <mutex>
-#include <utility>
-
-#include <google/protobuf/port_def.inc>
-
-namespace google {
-namespace protobuf {
-namespace internal {
-
-using once_flag = std::once_flag;
-template <typename... Args>
-void call_once(Args&&... args ) {
-  std::call_once(std::forward<Args>(args)...);
-}
-
-}  // namespace internal
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_ONCE_H__
diff --git a/include/google/protobuf/stubs/platform_macros.h b/include/google/protobuf/stubs/platform_macros.h
deleted file mode 100644
index f50efdfb71..0000000000
--- a/include/google/protobuf/stubs/platform_macros.h
+++ /dev/null
@@ -1,142 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2012 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_PLATFORM_MACROS_H_
-#define GOOGLE_PROTOBUF_PLATFORM_MACROS_H_
-
-#define GOOGLE_PROTOBUF_PLATFORM_ERROR \
-#error "Host platform was not detected as supported by protobuf"
-
-// Processor architecture detection.  For more info on what's defined, see:
-//   http://msdn.microsoft.com/en-us/library/b0084kay.aspx
-//   http://www.agner.org/optimize/calling_conventions.pdf
-//   or with gcc, run: "echo | gcc -E -dM -"
-#if defined(_M_X64) || defined(__x86_64__)
-#define GOOGLE_PROTOBUF_ARCH_X64 1
-#define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-#elif defined(_M_IX86) || defined(__i386__)
-#define GOOGLE_PROTOBUF_ARCH_IA32 1
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#elif defined(__QNX__)
-#define GOOGLE_PROTOBUF_ARCH_ARM_QNX 1
-#if defined(__aarch64__)
-#define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-#else
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#endif
-#elif defined(_M_ARM) || defined(__ARMEL__)
-#define GOOGLE_PROTOBUF_ARCH_ARM 1
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#elif defined(_M_ARM64)
-#define GOOGLE_PROTOBUF_ARCH_ARM 1
-#define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-#elif defined(__aarch64__)
-#define GOOGLE_PROTOBUF_ARCH_AARCH64 1
-#define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-#elif defined(__mips__)
-#if defined(__LP64__)
-#define GOOGLE_PROTOBUF_ARCH_MIPS64 1
-#define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-#else
-#define GOOGLE_PROTOBUF_ARCH_MIPS 1
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#endif
-#elif defined(__pnacl__)
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#elif defined(sparc)
-#define GOOGLE_PROTOBUF_ARCH_SPARC 1
-#if defined(__sparc_v9__) || defined(__sparcv9) || defined(__arch64__)
-#define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-#else
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#endif
-#elif defined(_POWER) || defined(__powerpc64__) || defined(__PPC64__)
-#define GOOGLE_PROTOBUF_ARCH_POWER 1
-#define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-#elif defined(__PPC__)
-#define GOOGLE_PROTOBUF_ARCH_PPC 1
-#define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-#elif defined(__GNUC__)
-# if (((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)) || (__GNUC__ > 4))
-// We fallback to the generic Clang/GCC >= 4.7 implementation in atomicops.h
-# elif defined(__clang__)
-#  if !__has_extension(c_atomic)
-GOOGLE_PROTOBUF_PLATFORM_ERROR
-#  endif
-// We fallback to the generic Clang/GCC >= 4.7 implementation in atomicops.h
-# endif
-# if __LP64__
-#  define GOOGLE_PROTOBUF_ARCH_64_BIT 1
-# else
-#  define GOOGLE_PROTOBUF_ARCH_32_BIT 1
-# endif
-#else
-GOOGLE_PROTOBUF_PLATFORM_ERROR
-#endif
-
-#if defined(__APPLE__)
-#define GOOGLE_PROTOBUF_OS_APPLE
-#include <Availability.h>
-#include <TargetConditionals.h>
-#if TARGET_OS_IPHONE
-#define GOOGLE_PROTOBUF_OS_IPHONE
-#endif
-#elif defined(__EMSCRIPTEN__)
-#define GOOGLE_PROTOBUF_OS_EMSCRIPTEN
-#elif defined(__native_client__)
-#define GOOGLE_PROTOBUF_OS_NACL
-#elif defined(sun)
-#define GOOGLE_PROTOBUF_OS_SOLARIS
-#elif defined(_AIX)
-#define GOOGLE_PROTOBUF_OS_AIX
-#elif defined(__ANDROID__)
-#define GOOGLE_PROTOBUF_OS_ANDROID
-#endif
-
-#undef GOOGLE_PROTOBUF_PLATFORM_ERROR
-
-#if defined(GOOGLE_PROTOBUF_OS_ANDROID) || defined(GOOGLE_PROTOBUF_OS_IPHONE) || defined(__OpenBSD__)
-// Android ndk does not support the __thread keyword very well yet. Here
-// we use pthread_key_create()/pthread_getspecific()/... methods for
-// TLS support on android.
-// iOS and OpenBSD also do not support the __thread keyword.
-#define GOOGLE_PROTOBUF_NO_THREADLOCAL
-#endif
-
-#if defined(__MAC_OS_X_VERSION_MIN_REQUIRED) && __MAC_OS_X_VERSION_MIN_REQUIRED < 1070
-// __thread keyword requires at least 10.7
-#define GOOGLE_PROTOBUF_NO_THREADLOCAL
-#endif
-
-#ifndef PROTOBUF_USE_DLLS
-#define PROTOBUF_USE_DLLS
-#endif // PROTOBUF_USE_DLLS
-
-#endif  // GOOGLE_PROTOBUF_PLATFORM_MACROS_H_
diff --git a/include/google/protobuf/stubs/port.h b/include/google/protobuf/stubs/port.h
deleted file mode 100644
index b074cb1630..0000000000
--- a/include/google/protobuf/stubs/port.h
+++ /dev/null
@@ -1,413 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_STUBS_PORT_H_
-#define GOOGLE_PROTOBUF_STUBS_PORT_H_
-
-#include <assert.h>
-#include <cstdint>
-#include <stdlib.h>
-#include <cstddef>
-#include <string>
-#include <string.h>
-
-#include <google/protobuf/stubs/platform_macros.h>
-
-#include <google/protobuf/port_def.inc>
-
-#undef PROTOBUF_LITTLE_ENDIAN
-#ifdef _WIN32
-  // Assuming windows is always little-endian.
-  // TODO(xiaofeng): The PROTOBUF_LITTLE_ENDIAN is not only used for
-  // optimization but also for correctness. We should define an
-  // different macro to test the big-endian code path in coded_stream.
-  #if !defined(PROTOBUF_DISABLE_LITTLE_ENDIAN_OPT_FOR_TEST)
-    #define PROTOBUF_LITTLE_ENDIAN 1
-  #endif
-#if defined(_MSC_VER) && _MSC_VER >= 1300 && !defined(__INTEL_COMPILER)
-// If MSVC has "/RTCc" set, it will complain about truncating casts at
-// runtime.  This file contains some intentional truncating casts.
-#pragma runtime_checks("c", off)
-#endif
-#else
-#ifdef __APPLE__
-#include <machine/endian.h>  // __BYTE_ORDER
-#elif defined(__FreeBSD__)
-#include <sys/endian.h>  // __BYTE_ORDER
-#elif (defined(sun) || defined(__sun)) && (defined(__SVR4) || defined(__svr4__))
-#include <sys/isa_defs.h>  // __BYTE_ORDER
-#elif defined(_AIX) || defined(__TOS_AIX__)
-#include <sys/machine.h>  // BYTE_ORDER
-#else
-#if !defined(__QNX__)
-#include <endian.h>  // __BYTE_ORDER
-#endif
-#endif
-#if ((defined(__LITTLE_ENDIAN__) && !defined(__BIG_ENDIAN__)) ||   \
-     (defined(__BYTE_ORDER) && __BYTE_ORDER == __LITTLE_ENDIAN) || \
-     (defined(BYTE_ORDER) && BYTE_ORDER == LITTLE_ENDIAN)) &&      \
-    !defined(PROTOBUF_DISABLE_LITTLE_ENDIAN_OPT_FOR_TEST)
-#define PROTOBUF_LITTLE_ENDIAN 1
-#endif
-#endif
-
-// These #includes are for the byte swap functions declared later on.
-#ifdef _MSC_VER
-#include <stdlib.h>  // NOLINT(build/include)
-#include <intrin.h>
-#elif defined(__APPLE__)
-#include <libkern/OSByteOrder.h>
-#elif defined(__linux__) || defined(__ANDROID__) || defined(__CYGWIN__)
-#include <byteswap.h>  // IWYU pragma: export
-#endif
-
-// Legacy: some users reference these (internal-only) macros even though we
-// don't need them any more.
-#if defined(_MSC_VER) && defined(PROTOBUF_USE_DLLS)
-  #ifdef LIBPROTOBUF_EXPORTS
-    #define LIBPROTOBUF_EXPORT __declspec(dllexport)
-  #else
-    #define LIBPROTOBUF_EXPORT __declspec(dllimport)
-  #endif
-  #ifdef LIBPROTOC_EXPORTS
-    #define LIBPROTOC_EXPORT   __declspec(dllexport)
-  #else
-    #define LIBPROTOC_EXPORT   __declspec(dllimport)
-  #endif
-#else
-  #define LIBPROTOBUF_EXPORT
-  #define LIBPROTOC_EXPORT
-#endif
-
-#define PROTOBUF_RUNTIME_DEPRECATED(message) PROTOBUF_DEPRECATED_MSG(message)
-#define GOOGLE_PROTOBUF_RUNTIME_DEPRECATED(message) \
-  PROTOBUF_DEPRECATED_MSG(message)
-
-// ===================================================================
-// from google3/base/port.h
-
-#if (defined(__GXX_EXPERIMENTAL_CXX0X__) || __cplusplus >= 201103L || \
-     (defined(_MSC_VER) && _MSC_VER >= 1900))
-// Define this to 1 if the code is compiled in C++11 mode; leave it
-// undefined otherwise.  Do NOT define it to 0 -- that causes
-// '#ifdef LANG_CXX11' to behave differently from '#if LANG_CXX11'.
-#define LANG_CXX11 1
-#else
-#error "Protobuf requires at least C++11."
-#endif
-
-namespace google {
-namespace protobuf {
-
-using ConstStringParam = const std::string &;
-
-typedef unsigned int uint;
-
-typedef int8_t int8;
-typedef int16_t int16;
-typedef int32_t int32;
-typedef int64_t int64;
-
-typedef uint8_t uint8;
-typedef uint16_t uint16;
-typedef uint32_t uint32;
-typedef uint64_t uint64;
-
-static const int32 kint32max = 0x7FFFFFFF;
-static const int32 kint32min = -kint32max - 1;
-static const int64 kint64max = int64_t{0x7FFFFFFFFFFFFFFF};
-static const int64 kint64min = -kint64max - 1;
-static const uint32 kuint32max = 0xFFFFFFFFu;
-static const uint64 kuint64max = uint64_t{0xFFFFFFFFFFFFFFFFu};
-
-#if defined(ADDRESS_SANITIZER) || defined(THREAD_SANITIZER) ||\
-    defined(MEMORY_SANITIZER)
-
-#ifdef __cplusplus
-extern "C" {
-#endif  // __cplusplus
-uint16_t __sanitizer_unaligned_load16(const void *p);
-uint32_t __sanitizer_unaligned_load32(const void *p);
-uint64_t __sanitizer_unaligned_load64(const void *p);
-void __sanitizer_unaligned_store16(void *p, uint16_t v);
-void __sanitizer_unaligned_store32(void *p, uint32_t v);
-void __sanitizer_unaligned_store64(void *p, uint64_t v);
-#ifdef __cplusplus
-}  // extern "C"
-#endif  // __cplusplus
-
-inline uint16_t GOOGLE_UNALIGNED_LOAD16(const void *p) {
-  return __sanitizer_unaligned_load16(p);
-}
-
-inline uint32_t GOOGLE_UNALIGNED_LOAD32(const void *p) {
-  return __sanitizer_unaligned_load32(p);
-}
-
-inline uint64_t GOOGLE_UNALIGNED_LOAD64(const void *p) {
-  return __sanitizer_unaligned_load64(p);
-}
-
-inline void GOOGLE_UNALIGNED_STORE16(void *p, uint16_t v) {
-  __sanitizer_unaligned_store16(p, v);
-}
-
-inline void GOOGLE_UNALIGNED_STORE32(void *p, uint32_t v) {
-  __sanitizer_unaligned_store32(p, v);
-}
-
-inline void GOOGLE_UNALIGNED_STORE64(void *p, uint64_t v) {
-  __sanitizer_unaligned_store64(p, v);
-}
-
-#elif defined(GOOGLE_PROTOBUF_USE_UNALIGNED) && GOOGLE_PROTOBUF_USE_UNALIGNED
-
-#define GOOGLE_UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16_t *>(_p))
-#define GOOGLE_UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32_t *>(_p))
-#define GOOGLE_UNALIGNED_LOAD64(_p) (*reinterpret_cast<const uint64_t *>(_p))
-
-#define GOOGLE_UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16_t *>(_p) = (_val))
-#define GOOGLE_UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32_t *>(_p) = (_val))
-#define GOOGLE_UNALIGNED_STORE64(_p, _val) (*reinterpret_cast<uint64_t *>(_p) = (_val))
-
-#else
-inline uint16_t GOOGLE_UNALIGNED_LOAD16(const void *p) {
-  uint16_t t;
-  memcpy(&t, p, sizeof t);
-  return t;
-}
-
-inline uint32_t GOOGLE_UNALIGNED_LOAD32(const void *p) {
-  uint32_t t;
-  memcpy(&t, p, sizeof t);
-  return t;
-}
-
-inline uint64_t GOOGLE_UNALIGNED_LOAD64(const void *p) {
-  uint64_t t;
-  memcpy(&t, p, sizeof t);
-  return t;
-}
-
-inline void GOOGLE_UNALIGNED_STORE16(void *p, uint16_t v) {
-  memcpy(p, &v, sizeof v);
-}
-
-inline void GOOGLE_UNALIGNED_STORE32(void *p, uint32_t v) {
-  memcpy(p, &v, sizeof v);
-}
-
-inline void GOOGLE_UNALIGNED_STORE64(void *p, uint64_t v) {
-  memcpy(p, &v, sizeof v);
-}
-#endif
-
-#if defined(GOOGLE_PROTOBUF_OS_NACL) \
-    || (defined(__ANDROID__) && defined(__clang__) \
-        && (__clang_major__ == 3 && __clang_minor__ == 8) \
-        && (__clang_patchlevel__ < 275480))
-# define GOOGLE_PROTOBUF_USE_PORTABLE_LOG2
-#endif
-
-// The following guarantees declaration of the byte swap functions.
-#ifdef _MSC_VER
-#define bswap_16(x) _byteswap_ushort(x)
-#define bswap_32(x) _byteswap_ulong(x)
-#define bswap_64(x) _byteswap_uint64(x)
-
-#elif defined(__APPLE__)
-// Mac OS X / Darwin features
-#define bswap_16(x) OSSwapInt16(x)
-#define bswap_32(x) OSSwapInt32(x)
-#define bswap_64(x) OSSwapInt64(x)
-
-#elif !defined(__linux__) && !defined(__ANDROID__) && !defined(__CYGWIN__)
-
-#ifndef bswap_16
-static inline uint16_t bswap_16(uint16_t x) {
-  return static_cast<uint16_t>(((x & 0xFF) << 8) | ((x & 0xFF00) >> 8));
-}
-#define bswap_16(x) bswap_16(x)
-#endif
-
-#ifndef bswap_32
-static inline uint32_t bswap_32(uint32_t x) {
-  return (((x & 0xFF) << 24) |
-          ((x & 0xFF00) << 8) |
-          ((x & 0xFF0000) >> 8) |
-          ((x & 0xFF000000) >> 24));
-}
-#define bswap_32(x) bswap_32(x)
-#endif
-
-#ifndef bswap_64
-static inline uint64_t bswap_64(uint64_t x) {
-  return (((x & uint64_t{0xFFu}) << 56) | ((x & uint64_t{0xFF00u}) << 40) |
-          ((x & uint64_t{0xFF0000u}) << 24) |
-          ((x & uint64_t{0xFF000000u}) << 8) |
-          ((x & uint64_t{0xFF00000000u}) >> 8) |
-          ((x & uint64_t{0xFF0000000000u}) >> 24) |
-          ((x & uint64_t{0xFF000000000000u}) >> 40) |
-          ((x & uint64_t{0xFF00000000000000u}) >> 56));
-}
-#define bswap_64(x) bswap_64(x)
-#endif
-
-#endif
-
-// ===================================================================
-// from google3/util/bits/bits.h
-
-class Bits {
- public:
-  static uint32_t Log2FloorNonZero(uint32_t n) {
-#if defined(__GNUC__)
-  return 31 ^ static_cast<uint32_t>(__builtin_clz(n));
-#elif defined(_MSC_VER)
-  unsigned long where;
-  _BitScanReverse(&where, n);
-  return where;
-#else
-  return Log2FloorNonZero_Portable(n);
-#endif
-  }
-
-  static uint32_t Log2FloorNonZero64(uint64_t n) {
-    // Older versions of clang run into an instruction-selection failure when
-    // it encounters __builtin_clzll:
-    // https://bugs.chromium.org/p/nativeclient/issues/detail?id=4395
-    // This includes arm-nacl-clang and clang in older Android NDK versions.
-    // To work around this, when we build with those we use the portable
-    // implementation instead.
-#if defined(__GNUC__) && !defined(GOOGLE_PROTOBUF_USE_PORTABLE_LOG2)
-  return 63 ^ static_cast<uint32_t>(__builtin_clzll(n));
-#elif defined(_MSC_VER) && defined(_M_X64)
-  unsigned long where;
-  _BitScanReverse64(&where, n);
-  return where;
-#else
-  return Log2FloorNonZero64_Portable(n);
-#endif
-  }
- private:
-  static int Log2FloorNonZero_Portable(uint32_t n) {
-    if (n == 0)
-      return -1;
-    int log = 0;
-    uint32_t value = n;
-    for (int i = 4; i >= 0; --i) {
-      int shift = (1 << i);
-      uint32_t x = value >> shift;
-      if (x != 0) {
-        value = x;
-        log += shift;
-      }
-    }
-    assert(value == 1);
-    return log;
-  }
-
-  static int Log2FloorNonZero64_Portable(uint64_t n) {
-    const uint32_t topbits = static_cast<uint32_t>(n >> 32);
-    if (topbits == 0) {
-      // Top bits are zero, so scan in bottom bits
-      return static_cast<int>(Log2FloorNonZero(static_cast<uint32_t>(n)));
-    } else {
-      return 32 + static_cast<int>(Log2FloorNonZero(topbits));
-    }
-  }
-};
-
-// ===================================================================
-// from google3/util/endian/endian.h
-PROTOBUF_EXPORT uint32_t ghtonl(uint32_t x);
-
-class BigEndian {
- public:
-#ifdef PROTOBUF_LITTLE_ENDIAN
-
-  static uint16_t FromHost16(uint16_t x) { return bswap_16(x); }
-  static uint16_t ToHost16(uint16_t x) { return bswap_16(x); }
-
-  static uint32_t FromHost32(uint32_t x) { return bswap_32(x); }
-  static uint32_t ToHost32(uint32_t x) { return bswap_32(x); }
-
-  static uint64_t FromHost64(uint64_t x) { return bswap_64(x); }
-  static uint64_t ToHost64(uint64_t x) { return bswap_64(x); }
-
-  static bool IsLittleEndian() { return true; }
-
-#else
-
-  static uint16_t FromHost16(uint16_t x) { return x; }
-  static uint16_t ToHost16(uint16_t x) { return x; }
-
-  static uint32_t FromHost32(uint32_t x) { return x; }
-  static uint32_t ToHost32(uint32_t x) { return x; }
-
-  static uint64_t FromHost64(uint64_t x) { return x; }
-  static uint64_t ToHost64(uint64_t x) { return x; }
-
-  static bool IsLittleEndian() { return false; }
-
-#endif /* ENDIAN */
-
-  // Functions to do unaligned loads and stores in big-endian order.
-  static uint16_t Load16(const void *p) {
-    return ToHost16(GOOGLE_UNALIGNED_LOAD16(p));
-  }
-
-  static void Store16(void *p, uint16_t v) {
-    GOOGLE_UNALIGNED_STORE16(p, FromHost16(v));
-  }
-
-  static uint32_t Load32(const void *p) {
-    return ToHost32(GOOGLE_UNALIGNED_LOAD32(p));
-  }
-
-  static void Store32(void *p, uint32_t v) {
-    GOOGLE_UNALIGNED_STORE32(p, FromHost32(v));
-  }
-
-  static uint64_t Load64(const void *p) {
-    return ToHost64(GOOGLE_UNALIGNED_LOAD64(p));
-  }
-
-  static void Store64(void *p, uint64_t v) {
-    GOOGLE_UNALIGNED_STORE64(p, FromHost64(v));
-  }
-};
-
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_PORT_H_
diff --git a/include/google/protobuf/stubs/status.h b/include/google/protobuf/stubs/status.h
deleted file mode 100644
index c858cf6239..0000000000
--- a/include/google/protobuf/stubs/status.h
+++ /dev/null
@@ -1,196 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef GOOGLE_PROTOBUF_STUBS_STATUS_H_
-#define GOOGLE_PROTOBUF_STUBS_STATUS_H_
-
-#include <string>
-
-#include <google/protobuf/stubs/stringpiece.h>
-
-#include <google/protobuf/port_def.inc>
-
-namespace google {
-namespace protobuf {
-namespace util {
-namespace status_internal {
-
-// These values must match error codes defined in google/rpc/code.proto.
-enum class StatusCode : int {
-  kOk = 0,
-  kCancelled = 1,
-  kUnknown = 2,
-  kInvalidArgument = 3,
-  kDeadlineExceeded = 4,
-  kNotFound = 5,
-  kAlreadyExists = 6,
-  kPermissionDenied = 7,
-  kUnauthenticated = 16,
-  kResourceExhausted = 8,
-  kFailedPrecondition = 9,
-  kAborted = 10,
-  kOutOfRange = 11,
-  kUnimplemented = 12,
-  kInternal = 13,
-  kUnavailable = 14,
-  kDataLoss = 15,
-};
-
-class PROTOBUF_EXPORT Status {
- public:
-  // Creates a "successful" status.
-  Status();
-
-  // Create a status in the canonical error space with the specified
-  // code, and error message.  If "code == 0", error_message is
-  // ignored and a Status object identical to Status::kOk is
-  // constructed.
-  Status(StatusCode error_code, StringPiece error_message);
-  Status(const Status&);
-  Status& operator=(const Status& x);
-  ~Status() {}
-
-  // Accessor
-  bool ok() const { return error_code_ == StatusCode::kOk; }
-  StatusCode code() const { return error_code_; }
-  StringPiece message() const {
-    return error_message_;
-  }
-
-  bool operator==(const Status& x) const;
-  bool operator!=(const Status& x) const {
-    return !operator==(x);
-  }
-
-  // Return a combination of the error code name and message.
-  std::string ToString() const;
-
- private:
-  StatusCode error_code_;
-  std::string error_message_;
-};
-
-// Returns an OK status, equivalent to a default constructed instance. Prefer
-// usage of `OkStatus()` when constructing such an OK status.
-PROTOBUF_EXPORT Status OkStatus();
-
-// Prints a human-readable representation of 'x' to 'os'.
-PROTOBUF_EXPORT std::ostream& operator<<(std::ostream& os, const Status& x);
-
-// These convenience functions return `true` if a given status matches the
-// `StatusCode` error code of its associated function.
-PROTOBUF_EXPORT bool IsAborted(const Status& status);
-PROTOBUF_EXPORT bool IsAlreadyExists(const Status& status);
-PROTOBUF_EXPORT bool IsCancelled(const Status& status);
-PROTOBUF_EXPORT bool IsDataLoss(const Status& status);
-PROTOBUF_EXPORT bool IsDeadlineExceeded(const Status& status);
-PROTOBUF_EXPORT bool IsFailedPrecondition(const Status& status);
-PROTOBUF_EXPORT bool IsInternal(const Status& status);
-PROTOBUF_EXPORT bool IsInvalidArgument(const Status& status);
-PROTOBUF_EXPORT bool IsNotFound(const Status& status);
-PROTOBUF_EXPORT bool IsOutOfRange(const Status& status);
-PROTOBUF_EXPORT bool IsPermissionDenied(const Status& status);
-PROTOBUF_EXPORT bool IsResourceExhausted(const Status& status);
-PROTOBUF_EXPORT bool IsUnauthenticated(const Status& status);
-PROTOBUF_EXPORT bool IsUnavailable(const Status& status);
-PROTOBUF_EXPORT bool IsUnimplemented(const Status& status);
-PROTOBUF_EXPORT bool IsUnknown(const Status& status);
-
-// These convenience functions create an `Status` object with an error code as
-// indicated by the associated function name, using the error message passed in
-// `message`.
-//
-// These functions are intentionally named `*Error` rather than `*Status` to
-// match the names from Abseil:
-// https://github.com/abseil/abseil-cpp/blob/2e9532cc6c701a8323d0cffb468999ab804095ab/absl/status/status.h#L716
-PROTOBUF_EXPORT Status AbortedError(StringPiece message);
-PROTOBUF_EXPORT Status AlreadyExistsError(StringPiece message);
-PROTOBUF_EXPORT Status CancelledError(StringPiece message);
-PROTOBUF_EXPORT Status DataLossError(StringPiece message);
-PROTOBUF_EXPORT Status DeadlineExceededError(StringPiece message);
-PROTOBUF_EXPORT Status FailedPreconditionError(StringPiece message);
-PROTOBUF_EXPORT Status InternalError(StringPiece message);
-PROTOBUF_EXPORT Status InvalidArgumentError(StringPiece message);
-PROTOBUF_EXPORT Status NotFoundError(StringPiece message);
-PROTOBUF_EXPORT Status OutOfRangeError(StringPiece message);
-PROTOBUF_EXPORT Status PermissionDeniedError(StringPiece message);
-PROTOBUF_EXPORT Status ResourceExhaustedError(StringPiece message);
-PROTOBUF_EXPORT Status UnauthenticatedError(StringPiece message);
-PROTOBUF_EXPORT Status UnavailableError(StringPiece message);
-PROTOBUF_EXPORT Status UnimplementedError(StringPiece message);
-PROTOBUF_EXPORT Status UnknownError(StringPiece message);
-
-}  // namespace status_internal
-
-using ::google::protobuf::util::status_internal::Status;
-using ::google::protobuf::util::status_internal::StatusCode;
-
-using ::google::protobuf::util::status_internal::IsAborted;
-using ::google::protobuf::util::status_internal::IsAlreadyExists;
-using ::google::protobuf::util::status_internal::IsCancelled;
-using ::google::protobuf::util::status_internal::IsDataLoss;
-using ::google::protobuf::util::status_internal::IsDeadlineExceeded;
-using ::google::protobuf::util::status_internal::IsFailedPrecondition;
-using ::google::protobuf::util::status_internal::IsInternal;
-using ::google::protobuf::util::status_internal::IsInvalidArgument;
-using ::google::protobuf::util::status_internal::IsNotFound;
-using ::google::protobuf::util::status_internal::IsOutOfRange;
-using ::google::protobuf::util::status_internal::IsPermissionDenied;
-using ::google::protobuf::util::status_internal::IsResourceExhausted;
-using ::google::protobuf::util::status_internal::IsUnauthenticated;
-using ::google::protobuf::util::status_internal::IsUnavailable;
-using ::google::protobuf::util::status_internal::IsUnimplemented;
-using ::google::protobuf::util::status_internal::IsUnknown;
-
-using ::google::protobuf::util::status_internal::AbortedError;
-using ::google::protobuf::util::status_internal::AlreadyExistsError;
-using ::google::protobuf::util::status_internal::CancelledError;
-using ::google::protobuf::util::status_internal::DataLossError;
-using ::google::protobuf::util::status_internal::DeadlineExceededError;
-using ::google::protobuf::util::status_internal::FailedPreconditionError;
-using ::google::protobuf::util::status_internal::InternalError;
-using ::google::protobuf::util::status_internal::InvalidArgumentError;
-using ::google::protobuf::util::status_internal::NotFoundError;
-using ::google::protobuf::util::status_internal::OkStatus;
-using ::google::protobuf::util::status_internal::OutOfRangeError;
-using ::google::protobuf::util::status_internal::PermissionDeniedError;
-using ::google::protobuf::util::status_internal::ResourceExhaustedError;
-using ::google::protobuf::util::status_internal::UnauthenticatedError;
-using ::google::protobuf::util::status_internal::UnavailableError;
-using ::google::protobuf::util::status_internal::UnimplementedError;
-using ::google::protobuf::util::status_internal::UnknownError;
-
-}  // namespace util
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_STATUS_H_
diff --git a/include/google/protobuf/stubs/stl_util.h b/include/google/protobuf/stubs/stl_util.h
deleted file mode 100644
index e6260d0760..0000000000
--- a/include/google/protobuf/stubs/stl_util.h
+++ /dev/null
@@ -1,90 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// from google3/util/gtl/stl_util.h
-
-#ifndef GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
-#define GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
-
-#include <google/protobuf/stubs/common.h>
-
-#include <algorithm>
-
-// Must be last.
-#include <google/protobuf/port_def.inc>  // NOLINT
-
-namespace google {
-namespace protobuf {
-
-// Inside Google, this function implements a horrible, disgusting hack in which
-// we reach into the string's private implementation and resize it without
-// initializing the new bytes.  In some cases doing this can significantly
-// improve performance.  However, since it's totally non-portable it has no
-// place in open source code.  Feel free to fill this function in with your
-// own disgusting hack if you want the perf boost.
-inline void STLStringResizeUninitialized(std::string* s, size_t new_size) {
-  s->resize(new_size);
-}
-
-// As above, but we make sure to follow amortized growth in which we always
-// increase the capacity by at least a constant factor >1.
-inline void STLStringResizeUninitializedAmortized(std::string* s,
-                                                  size_t new_size) {
-  const size_t cap = s->capacity();
-  if (new_size > cap) {
-    // Make sure to always grow by at least a factor of 2x.
-    s->reserve(std::max<size_t>(new_size, 2 * cap));
-  }
-  STLStringResizeUninitialized(s, new_size);
-}
-
-// Return a mutable char* pointing to a string's internal buffer,
-// which may not be null-terminated. Writing through this pointer will
-// modify the string.
-//
-// string_as_array(&str)[i] is valid for 0 <= i < str.size() until the
-// next call to a string method that invalidates iterators.
-//
-// As of 2006-04, there is no standard-blessed way of getting a
-// mutable reference to a string's internal buffer. However, issue 530
-// (http://www.open-std.org/JTC1/SC22/WG21/docs/lwg-active.html#530)
-// proposes this as the method. According to Matt Austern, this should
-// already work on all current implementations.
-inline char* string_as_array(std::string* str) {
-  // DO NOT USE const_cast<char*>(str->data())! See the unittest for why.
-  return str->empty() ? nullptr : &*str->begin();
-}
-
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>  // NOLINT
-
-#endif  // GOOGLE_PROTOBUF_STUBS_STL_UTIL_H__
diff --git a/include/google/protobuf/stubs/stringpiece.h b/include/google/protobuf/stubs/stringpiece.h
deleted file mode 100644
index c63e25b254..0000000000
--- a/include/google/protobuf/stubs/stringpiece.h
+++ /dev/null
@@ -1,402 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// A StringPiece points to part or all of a string, Cord, double-quoted string
-// literal, or other string-like object.  A StringPiece does *not* own the
-// string to which it points.  A StringPiece is not null-terminated.
-//
-// You can use StringPiece as a function or method parameter.  A StringPiece
-// parameter can receive a double-quoted string literal argument, a "const
-// char*" argument, a string argument, or a StringPiece argument with no data
-// copying.  Systematic use of StringPiece for arguments reduces data
-// copies and strlen() calls.
-//
-// Prefer passing StringPieces by value:
-//   void MyFunction(StringPiece arg);
-// If circumstances require, you may also pass by const reference:
-//   void MyFunction(const StringPiece& arg);  // not preferred
-// Both of these have the same lifetime semantics.  Passing by value
-// generates slightly smaller code.  For more discussion, see the thread
-// go/stringpiecebyvalue on c-users.
-//
-// StringPiece is also suitable for local variables if you know that
-// the lifetime of the underlying object is longer than the lifetime
-// of your StringPiece variable.
-//
-// Beware of binding a StringPiece to a temporary:
-//   StringPiece sp = obj.MethodReturningString();  // BAD: lifetime problem
-//
-// This code is okay:
-//   string str = obj.MethodReturningString();  // str owns its contents
-//   StringPiece sp(str);  // GOOD, because str outlives sp
-//
-// StringPiece is sometimes a poor choice for a return value and usually a poor
-// choice for a data member.  If you do use a StringPiece this way, it is your
-// responsibility to ensure that the object pointed to by the StringPiece
-// outlives the StringPiece.
-//
-// A StringPiece may represent just part of a string; thus the name "Piece".
-// For example, when splitting a string, vector<StringPiece> is a natural data
-// type for the output.  For another example, a Cord is a non-contiguous,
-// potentially very long string-like object.  The Cord class has an interface
-// that iteratively provides StringPiece objects that point to the
-// successive pieces of a Cord object.
-//
-// A StringPiece is not null-terminated.  If you write code that scans a
-// StringPiece, you must check its length before reading any characters.
-// Common idioms that work on null-terminated strings do not work on
-// StringPiece objects.
-//
-// There are several ways to create a null StringPiece:
-//   StringPiece()
-//   StringPiece(nullptr)
-//   StringPiece(nullptr, 0)
-// For all of the above, sp.data() == nullptr, sp.length() == 0,
-// and sp.empty() == true.  Also, if you create a StringPiece with
-// a non-null pointer then sp.data() != nullptr.  Once created,
-// sp.data() will stay either nullptr or not-nullptr, except if you call
-// sp.clear() or sp.set().
-//
-// Thus, you can use StringPiece(nullptr) to signal an out-of-band value
-// that is different from other StringPiece values.  This is similar
-// to the way that const char* p1 = nullptr; is different from
-// const char* p2 = "";.
-//
-// There are many ways to create an empty StringPiece:
-//   StringPiece()
-//   StringPiece(nullptr)
-//   StringPiece(nullptr, 0)
-//   StringPiece("")
-//   StringPiece("", 0)
-//   StringPiece("abcdef", 0)
-//   StringPiece("abcdef"+6, 0)
-// For all of the above, sp.length() will be 0 and sp.empty() will be true.
-// For some empty StringPiece values, sp.data() will be nullptr.
-// For some empty StringPiece values, sp.data() will not be nullptr.
-//
-// Be careful not to confuse: null StringPiece and empty StringPiece.
-// The set of empty StringPieces properly includes the set of null StringPieces.
-// That is, every null StringPiece is an empty StringPiece,
-// but some non-null StringPieces are empty Stringpieces too.
-//
-// All empty StringPiece values compare equal to each other.
-// Even a null StringPieces compares equal to a non-null empty StringPiece:
-//  StringPiece() == StringPiece("", 0)
-//  StringPiece(nullptr) == StringPiece("abc", 0)
-//  StringPiece(nullptr, 0) == StringPiece("abcdef"+6, 0)
-//
-// Look carefully at this example:
-//   StringPiece("") == nullptr
-// True or false?  TRUE, because StringPiece::operator== converts
-// the right-hand side from nullptr to StringPiece(nullptr),
-// and then compares two zero-length spans of characters.
-// However, we are working to make this example produce a compile error.
-//
-// Suppose you want to write:
-//   bool TestWhat?(StringPiece sp) { return sp == nullptr; }  // BAD
-// Do not do that.  Write one of these instead:
-//   bool TestNull(StringPiece sp) { return sp.data() == nullptr; }
-//   bool TestEmpty(StringPiece sp) { return sp.empty(); }
-// The intent of TestWhat? is unclear.  Did you mean TestNull or TestEmpty?
-// Right now, TestWhat? behaves likes TestEmpty.
-// We are working to make TestWhat? produce a compile error.
-// TestNull is good to test for an out-of-band signal.
-// TestEmpty is good to test for an empty StringPiece.
-//
-// Caveats (again):
-// (1) The lifetime of the pointed-to string (or piece of a string)
-//     must be longer than the lifetime of the StringPiece.
-// (2) There may or may not be a '\0' character after the end of
-//     StringPiece data.
-// (3) A null StringPiece is empty.
-//     An empty StringPiece may or may not be a null StringPiece.
-
-#ifndef GOOGLE_PROTOBUF_STUBS_STRINGPIECE_H_
-#define GOOGLE_PROTOBUF_STUBS_STRINGPIECE_H_
-
-#include <assert.h>
-#include <stddef.h>
-#include <string.h>
-#include <iosfwd>
-#include <limits>
-#include <string>
-
-#if defined(__cpp_lib_string_view)
-#include <string_view>
-#endif
-
-#include <google/protobuf/stubs/hash.h>
-
-#include <google/protobuf/port_def.inc>
-
-namespace google {
-namespace protobuf {
-namespace stringpiece_internal {
-
-class PROTOBUF_EXPORT StringPiece {
- public:
-  using traits_type = std::char_traits<char>;
-  using value_type = char;
-  using pointer = char*;
-  using const_pointer = const char*;
-  using reference = char&;
-  using const_reference = const char&;
-  using const_iterator = const char*;
-  using iterator = const_iterator;
-  using const_reverse_iterator = std::reverse_iterator<const_iterator>;
-  using reverse_iterator = const_reverse_iterator;
-  using size_type = size_t;
-  using difference_type = std::ptrdiff_t;
-
- private:
-  const char* ptr_;
-  size_type length_;
-
-  static constexpr size_type kMaxSize =
-      (std::numeric_limits<difference_type>::max)();
-
-  static size_type CheckSize(size_type size) {
-#if !defined(NDEBUG) || defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0
-    if (PROTOBUF_PREDICT_FALSE(size > kMaxSize)) {
-      // Some people grep for this message in logs
-      // so take care if you ever change it.
-      LogFatalSizeTooBig(size, "string length exceeds max size");
-    }
-#endif
-    return size;
-  }
-
-  // Out-of-line error path.
-  static void LogFatalSizeTooBig(size_type size, const char* details);
-
- public:
-  // We provide non-explicit singleton constructors so users can pass
-  // in a "const char*" or a "string" wherever a "StringPiece" is
-  // expected.
-  //
-  // Style guide exception granted:
-  // http://goto/style-guide-exception-20978288
-  StringPiece() : ptr_(nullptr), length_(0) {}
-
-  StringPiece(const char* str)  // NOLINT(runtime/explicit)
-      : ptr_(str), length_(0) {
-    if (str != nullptr) {
-      length_ = CheckSize(strlen(str));
-    }
-  }
-
-  template <class Allocator>
-  StringPiece(  // NOLINT(runtime/explicit)
-      const std::basic_string<char, std::char_traits<char>, Allocator>& str)
-      : ptr_(str.data()), length_(0) {
-    length_ = CheckSize(str.size());
-  }
-
-#if defined(__cpp_lib_string_view)
-  StringPiece(  // NOLINT(runtime/explicit)
-      std::string_view str)
-      : ptr_(str.data()), length_(0) {
-    length_ = CheckSize(str.size());
-  }
-#endif
-
-  StringPiece(const char* offset, size_type len)
-      : ptr_(offset), length_(CheckSize(len)) {}
-
-  // data() may return a pointer to a buffer with embedded NULs, and the
-  // returned buffer may or may not be null terminated.  Therefore it is
-  // typically a mistake to pass data() to a routine that expects a NUL
-  // terminated string.
-  const_pointer data() const { return ptr_; }
-  size_type size() const { return length_; }
-  size_type length() const { return length_; }
-  bool empty() const { return length_ == 0; }
-
-  char operator[](size_type i) const {
-    assert(i < length_);
-    return ptr_[i];
-  }
-
-  void remove_prefix(size_type n) {
-    assert(length_ >= n);
-    ptr_ += n;
-    length_ -= n;
-  }
-
-  void remove_suffix(size_type n) {
-    assert(length_ >= n);
-    length_ -= n;
-  }
-
-  // returns {-1, 0, 1}
-  int compare(StringPiece x) const {
-    size_type min_size = length_ < x.length_ ? length_ : x.length_;
-    int r = memcmp(ptr_, x.ptr_, static_cast<size_t>(min_size));
-    if (r < 0) return -1;
-    if (r > 0) return 1;
-    if (length_ < x.length_) return -1;
-    if (length_ > x.length_) return 1;
-    return 0;
-  }
-
-  std::string as_string() const { return ToString(); }
-  // We also define ToString() here, since many other string-like
-  // interfaces name the routine that converts to a C++ string
-  // "ToString", and it's confusing to have the method that does that
-  // for a StringPiece be called "as_string()".  We also leave the
-  // "as_string()" method defined here for existing code.
-  std::string ToString() const {
-    if (ptr_ == nullptr) return "";
-    return std::string(data(), static_cast<size_type>(size()));
-  }
-
-  explicit operator std::string() const { return ToString(); }
-
-  void CopyToString(std::string* target) const;
-  void AppendToString(std::string* target) const;
-
-  bool starts_with(StringPiece x) const {
-    return (length_ >= x.length_) &&
-           (memcmp(ptr_, x.ptr_, static_cast<size_t>(x.length_)) == 0);
-  }
-
-  bool ends_with(StringPiece x) const {
-    return ((length_ >= x.length_) &&
-            (memcmp(ptr_ + (length_-x.length_), x.ptr_,
-                 static_cast<size_t>(x.length_)) == 0));
-  }
-
-  // Checks whether StringPiece starts with x and if so advances the beginning
-  // of it to past the match.  It's basically a shortcut for starts_with
-  // followed by remove_prefix.
-  bool Consume(StringPiece x);
-  // Like above but for the end of the string.
-  bool ConsumeFromEnd(StringPiece x);
-
-  // standard STL container boilerplate
-  static const size_type npos;
-  const_iterator begin() const { return ptr_; }
-  const_iterator end() const { return ptr_ + length_; }
-  const_reverse_iterator rbegin() const {
-    return const_reverse_iterator(ptr_ + length_);
-  }
-  const_reverse_iterator rend() const {
-    return const_reverse_iterator(ptr_);
-  }
-  size_type max_size() const { return length_; }
-  size_type capacity() const { return length_; }
-
-  // cpplint.py emits a false positive [build/include_what_you_use]
-  size_type copy(char* buf, size_type n, size_type pos = 0) const;  // NOLINT
-
-  bool contains(StringPiece s) const;
-
-  size_type find(StringPiece s, size_type pos = 0) const;
-  size_type find(char c, size_type pos = 0) const;
-  size_type rfind(StringPiece s, size_type pos = npos) const;
-  size_type rfind(char c, size_type pos = npos) const;
-
-  size_type find_first_of(StringPiece s, size_type pos = 0) const;
-  size_type find_first_of(char c, size_type pos = 0) const {
-    return find(c, pos);
-  }
-  size_type find_first_not_of(StringPiece s, size_type pos = 0) const;
-  size_type find_first_not_of(char c, size_type pos = 0) const;
-  size_type find_last_of(StringPiece s, size_type pos = npos) const;
-  size_type find_last_of(char c, size_type pos = npos) const {
-    return rfind(c, pos);
-  }
-  size_type find_last_not_of(StringPiece s, size_type pos = npos) const;
-  size_type find_last_not_of(char c, size_type pos = npos) const;
-
-  StringPiece substr(size_type pos, size_type n = npos) const;
-};
-
-// This large function is defined inline so that in a fairly common case where
-// one of the arguments is a literal, the compiler can elide a lot of the
-// following comparisons.
-inline bool operator==(StringPiece x, StringPiece y) {
-  StringPiece::size_type len = x.size();
-  if (len != y.size()) {
-    return false;
-  }
-
-  return x.data() == y.data() || len <= 0 ||
-      memcmp(x.data(), y.data(), static_cast<size_t>(len)) == 0;
-}
-
-inline bool operator!=(StringPiece x, StringPiece y) {
-  return !(x == y);
-}
-
-inline bool operator<(StringPiece x, StringPiece y) {
-  const StringPiece::size_type min_size =
-      x.size() < y.size() ? x.size() : y.size();
-  const int r = memcmp(x.data(), y.data(), static_cast<size_t>(min_size));
-  return (r < 0) || (r == 0 && x.size() < y.size());
-}
-
-inline bool operator>(StringPiece x, StringPiece y) {
-  return y < x;
-}
-
-inline bool operator<=(StringPiece x, StringPiece y) {
-  return !(x > y);
-}
-
-inline bool operator>=(StringPiece x, StringPiece y) {
-  return !(x < y);
-}
-
-// allow StringPiece to be logged
-extern std::ostream& operator<<(std::ostream& o, StringPiece piece);
-
-}  // namespace stringpiece_internal
-
-using ::google::protobuf::stringpiece_internal::StringPiece;
-
-}  // namespace protobuf
-}  // namespace google
-
-GOOGLE_PROTOBUF_HASH_NAMESPACE_DECLARATION_START
-template<> struct hash<StringPiece> {
-  size_t operator()(const StringPiece& s) const {
-    size_t result = 0;
-    for (const char *str = s.data(), *end = str + s.size(); str < end; str++) {
-      result = 5 * result + static_cast<size_t>(*str);
-    }
-    return result;
-  }
-};
-GOOGLE_PROTOBUF_HASH_NAMESPACE_DECLARATION_END
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // STRINGS_STRINGPIECE_H_
diff --git a/include/google/protobuf/stubs/strutil.h b/include/google/protobuf/stubs/strutil.h
deleted file mode 100644
index 9658abf908..0000000000
--- a/include/google/protobuf/stubs/strutil.h
+++ /dev/null
@@ -1,950 +0,0 @@
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// from google3/strings/strutil.h
-
-#ifndef GOOGLE_PROTOBUF_STUBS_STRUTIL_H__
-#define GOOGLE_PROTOBUF_STUBS_STRUTIL_H__
-
-#include <google/protobuf/stubs/common.h>
-#include <google/protobuf/stubs/stringpiece.h>
-#include <stdlib.h>
-
-#include <cstring>
-#include <google/protobuf/port_def.inc>
-#include <vector>
-
-namespace google {
-namespace protobuf {
-
-#if defined(_MSC_VER) && _MSC_VER < 1800
-#define strtoll  _strtoi64
-#define strtoull _strtoui64
-#elif defined(__DECCXX) && defined(__osf__)
-// HP C++ on Tru64 does not have strtoll, but strtol is already 64-bit.
-#define strtoll strtol
-#define strtoull strtoul
-#endif
-
-// ----------------------------------------------------------------------
-// ascii_isalnum()
-//    Check if an ASCII character is alphanumeric.  We can't use ctype's
-//    isalnum() because it is affected by locale.  This function is applied
-//    to identifiers in the protocol buffer language, not to natural-language
-//    strings, so locale should not be taken into account.
-// ascii_isdigit()
-//    Like above, but only accepts digits.
-// ascii_isspace()
-//    Check if the character is a space character.
-// ----------------------------------------------------------------------
-
-inline bool ascii_isalnum(char c) {
-  return ('a' <= c && c <= 'z') ||
-         ('A' <= c && c <= 'Z') ||
-         ('0' <= c && c <= '9');
-}
-
-inline bool ascii_isdigit(char c) {
-  return ('0' <= c && c <= '9');
-}
-
-inline bool ascii_isspace(char c) {
-  return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' ||
-      c == '\r';
-}
-
-inline bool ascii_isupper(char c) {
-  return c >= 'A' && c <= 'Z';
-}
-
-inline bool ascii_islower(char c) {
-  return c >= 'a' && c <= 'z';
-}
-
-inline char ascii_toupper(char c) {
-  return ascii_islower(c) ? c - ('a' - 'A') : c;
-}
-
-inline char ascii_tolower(char c) {
-  return ascii_isupper(c) ? c + ('a' - 'A') : c;
-}
-
-inline int hex_digit_to_int(char c) {
-  /* Assume ASCII. */
-  int x = static_cast<unsigned char>(c);
-  if (x > '9') {
-    x += 9;
-  }
-  return x & 0xf;
-}
-
-// ----------------------------------------------------------------------
-// HasPrefixString()
-//    Check if a string begins with a given prefix.
-// StripPrefixString()
-//    Given a string and a putative prefix, returns the string minus the
-//    prefix string if the prefix matches, otherwise the original
-//    string.
-// ----------------------------------------------------------------------
-inline bool HasPrefixString(StringPiece str, StringPiece prefix) {
-  return str.size() >= prefix.size() &&
-         memcmp(str.data(), prefix.data(), prefix.size()) == 0;
-}
-
-inline std::string StripPrefixString(const std::string& str,
-                                     const std::string& prefix) {
-  if (HasPrefixString(str, prefix)) {
-    return str.substr(prefix.size());
-  } else {
-    return str;
-  }
-}
-
-// ----------------------------------------------------------------------
-// HasSuffixString()
-//    Return true if str ends in suffix.
-// StripSuffixString()
-//    Given a string and a putative suffix, returns the string minus the
-//    suffix string if the suffix matches, otherwise the original
-//    string.
-// ----------------------------------------------------------------------
-inline bool HasSuffixString(StringPiece str, StringPiece suffix) {
-  return str.size() >= suffix.size() &&
-         memcmp(str.data() + str.size() - suffix.size(), suffix.data(),
-                suffix.size()) == 0;
-}
-
-inline std::string StripSuffixString(const std::string& str,
-                                     const std::string& suffix) {
-  if (HasSuffixString(str, suffix)) {
-    return str.substr(0, str.size() - suffix.size());
-  } else {
-    return str;
-  }
-}
-
-// ----------------------------------------------------------------------
-// ReplaceCharacters
-//    Replaces any occurrence of the character 'remove' (or the characters
-//    in 'remove') with the character 'replacewith'.
-//    Good for keeping html characters or protocol characters (\t) out
-//    of places where they might cause a problem.
-// StripWhitespace
-//    Removes whitespaces from both ends of the given string.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT void ReplaceCharacters(std::string* s, const char* remove,
-                                       char replacewith);
-
-PROTOBUF_EXPORT void StripWhitespace(std::string* s);
-
-// ----------------------------------------------------------------------
-// LowerString()
-// UpperString()
-// ToUpper()
-//    Convert the characters in "s" to lowercase or uppercase.  ASCII-only:
-//    these functions intentionally ignore locale because they are applied to
-//    identifiers used in the Protocol Buffer language, not to natural-language
-//    strings.
-// ----------------------------------------------------------------------
-
-inline void LowerString(std::string* s) {
-  std::string::iterator end = s->end();
-  for (std::string::iterator i = s->begin(); i != end; ++i) {
-    // tolower() changes based on locale.  We don't want this!
-    if ('A' <= *i && *i <= 'Z') *i += 'a' - 'A';
-  }
-}
-
-inline void UpperString(std::string* s) {
-  std::string::iterator end = s->end();
-  for (std::string::iterator i = s->begin(); i != end; ++i) {
-    // toupper() changes based on locale.  We don't want this!
-    if ('a' <= *i && *i <= 'z') *i += 'A' - 'a';
-  }
-}
-
-inline void ToUpper(std::string* s) { UpperString(s); }
-
-inline std::string ToUpper(const std::string& s) {
-  std::string out = s;
-  UpperString(&out);
-  return out;
-}
-
-// ----------------------------------------------------------------------
-// StringReplace()
-//    Give me a string and two patterns "old" and "new", and I replace
-//    the first instance of "old" in the string with "new", if it
-//    exists.  RETURN a new string, regardless of whether the replacement
-//    happened or not.
-// ----------------------------------------------------------------------
-
-PROTOBUF_EXPORT std::string StringReplace(const std::string& s,
-                                          const std::string& oldsub,
-                                          const std::string& newsub,
-                                          bool replace_all);
-
-// ----------------------------------------------------------------------
-// SplitStringUsing()
-//    Split a string using a character delimiter. Append the components
-//    to 'result'.  If there are consecutive delimiters, this function skips
-//    over all of them.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT void SplitStringUsing(StringPiece full, const char* delim,
-                                      std::vector<std::string>* res);
-
-// Split a string using one or more byte delimiters, presented
-// as a nul-terminated c string. Append the components to 'result'.
-// If there are consecutive delimiters, this function will return
-// corresponding empty strings.  If you want to drop the empty
-// strings, try SplitStringUsing().
-//
-// If "full" is the empty string, yields an empty string as the only value.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT void SplitStringAllowEmpty(StringPiece full, const char* delim,
-                                           std::vector<std::string>* result);
-
-// ----------------------------------------------------------------------
-// Split()
-//    Split a string using a character delimiter.
-// ----------------------------------------------------------------------
-inline std::vector<std::string> Split(StringPiece full, const char* delim,
-                                      bool skip_empty = true) {
-  std::vector<std::string> result;
-  if (skip_empty) {
-    SplitStringUsing(full, delim, &result);
-  } else {
-    SplitStringAllowEmpty(full, delim, &result);
-  }
-  return result;
-}
-
-// ----------------------------------------------------------------------
-// JoinStrings()
-//    These methods concatenate a vector of strings into a C++ string, using
-//    the C-string "delim" as a separator between components. There are two
-//    flavors of the function, one flavor returns the concatenated string,
-//    another takes a pointer to the target string. In the latter case the
-//    target string is cleared and overwritten.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT void JoinStrings(const std::vector<std::string>& components,
-                                 const char* delim, std::string* result);
-
-inline std::string JoinStrings(const std::vector<std::string>& components,
-                               const char* delim) {
-  std::string result;
-  JoinStrings(components, delim, &result);
-  return result;
-}
-
-// ----------------------------------------------------------------------
-// UnescapeCEscapeSequences()
-//    Copies "source" to "dest", rewriting C-style escape sequences
-//    -- '\n', '\r', '\\', '\ooo', etc -- to their ASCII
-//    equivalents.  "dest" must be sufficiently large to hold all
-//    the characters in the rewritten string (i.e. at least as large
-//    as strlen(source) + 1 should be safe, since the replacements
-//    are always shorter than the original escaped sequences).  It's
-//    safe for source and dest to be the same.  RETURNS the length
-//    of dest.
-//
-//    It allows hex sequences \xhh, or generally \xhhhhh with an
-//    arbitrary number of hex digits, but all of them together must
-//    specify a value of a single byte (e.g. \x0045 is equivalent
-//    to \x45, and \x1234 is erroneous).
-//
-//    It also allows escape sequences of the form \uhhhh (exactly four
-//    hex digits, upper or lower case) or \Uhhhhhhhh (exactly eight
-//    hex digits, upper or lower case) to specify a Unicode code
-//    point. The dest array will contain the UTF8-encoded version of
-//    that code-point (e.g., if source contains \u2019, then dest will
-//    contain the three bytes 0xE2, 0x80, and 0x99).
-//
-//    Errors: In the first form of the call, errors are reported with
-//    LOG(ERROR). The same is true for the second form of the call if
-//    the pointer to the string std::vector is nullptr; otherwise, error
-//    messages are stored in the std::vector. In either case, the effect on
-//    the dest array is not defined, but rest of the source will be
-//    processed.
-//    ----------------------------------------------------------------------
-
-PROTOBUF_EXPORT int UnescapeCEscapeSequences(const char* source, char* dest);
-PROTOBUF_EXPORT int UnescapeCEscapeSequences(const char* source, char* dest,
-                                             std::vector<std::string>* errors);
-
-// ----------------------------------------------------------------------
-// UnescapeCEscapeString()
-//    This does the same thing as UnescapeCEscapeSequences, but creates
-//    a new string. The caller does not need to worry about allocating
-//    a dest buffer. This should be used for non performance critical
-//    tasks such as printing debug messages. It is safe for src and dest
-//    to be the same.
-//
-//    The second call stores its errors in a supplied string vector.
-//    If the string vector pointer is nullptr, it reports the errors with LOG().
-//
-//    In the first and second calls, the length of dest is returned. In the
-//    the third call, the new string is returned.
-// ----------------------------------------------------------------------
-
-PROTOBUF_EXPORT int UnescapeCEscapeString(const std::string& src,
-                                          std::string* dest);
-PROTOBUF_EXPORT int UnescapeCEscapeString(const std::string& src,
-                                          std::string* dest,
-                                          std::vector<std::string>* errors);
-PROTOBUF_EXPORT std::string UnescapeCEscapeString(const std::string& src);
-
-// ----------------------------------------------------------------------
-// CEscape()
-//    Escapes 'src' using C-style escape sequences and returns the resulting
-//    string.
-//
-//    Escaped chars: \n, \r, \t, ", ', \, and !isprint().
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT std::string CEscape(const std::string& src);
-
-// ----------------------------------------------------------------------
-// CEscapeAndAppend()
-//    Escapes 'src' using C-style escape sequences, and appends the escaped
-//    string to 'dest'.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT void CEscapeAndAppend(StringPiece src, std::string* dest);
-
-namespace strings {
-// Like CEscape() but does not escape bytes with the upper bit set.
-PROTOBUF_EXPORT std::string Utf8SafeCEscape(const std::string& src);
-
-// Like CEscape() but uses hex (\x) escapes instead of octals.
-PROTOBUF_EXPORT std::string CHexEscape(const std::string& src);
-}  // namespace strings
-
-// ----------------------------------------------------------------------
-// strto32()
-// strtou32()
-// strto64()
-// strtou64()
-//    Architecture-neutral plug compatible replacements for strtol() and
-//    strtoul().  Long's have different lengths on ILP-32 and LP-64
-//    platforms, so using these is safer, from the point of view of
-//    overflow behavior, than using the standard libc functions.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT int32_t strto32_adaptor(const char* nptr, char** endptr,
-                                        int base);
-PROTOBUF_EXPORT uint32_t strtou32_adaptor(const char* nptr, char** endptr,
-                                          int base);
-
-inline int32_t strto32(const char *nptr, char **endptr, int base) {
-  if (sizeof(int32_t) == sizeof(long))
-    return strtol(nptr, endptr, base);
-  else
-    return strto32_adaptor(nptr, endptr, base);
-}
-
-inline uint32_t strtou32(const char *nptr, char **endptr, int base) {
-  if (sizeof(uint32_t) == sizeof(unsigned long))
-    return strtoul(nptr, endptr, base);
-  else
-    return strtou32_adaptor(nptr, endptr, base);
-}
-
-// For now, long long is 64-bit on all the platforms we care about, so these
-// functions can simply pass the call to strto[u]ll.
-inline int64_t strto64(const char *nptr, char **endptr, int base) {
-  static_assert(sizeof(int64_t) == sizeof(long long),
-                "sizeof int64_t is not sizeof long long");
-  return strtoll(nptr, endptr, base);
-}
-
-inline uint64_t strtou64(const char *nptr, char **endptr, int base) {
-  static_assert(sizeof(uint64_t) == sizeof(unsigned long long),
-                "sizeof uint64_t is not sizeof unsigned long long");
-  return strtoull(nptr, endptr, base);
-}
-
-// ----------------------------------------------------------------------
-// safe_strtob()
-// safe_strto32()
-// safe_strtou32()
-// safe_strto64()
-// safe_strtou64()
-// safe_strtof()
-// safe_strtod()
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT bool safe_strtob(StringPiece str, bool* value);
-
-PROTOBUF_EXPORT bool safe_strto32(const std::string& str, int32_t* value);
-PROTOBUF_EXPORT bool safe_strtou32(const std::string& str, uint32_t* value);
-inline bool safe_strto32(const char* str, int32_t* value) {
-  return safe_strto32(std::string(str), value);
-}
-inline bool safe_strto32(StringPiece str, int32_t* value) {
-  return safe_strto32(str.ToString(), value);
-}
-inline bool safe_strtou32(const char* str, uint32_t* value) {
-  return safe_strtou32(std::string(str), value);
-}
-inline bool safe_strtou32(StringPiece str, uint32_t* value) {
-  return safe_strtou32(str.ToString(), value);
-}
-
-PROTOBUF_EXPORT bool safe_strto64(const std::string& str, int64_t* value);
-PROTOBUF_EXPORT bool safe_strtou64(const std::string& str, uint64_t* value);
-inline bool safe_strto64(const char* str, int64_t* value) {
-  return safe_strto64(std::string(str), value);
-}
-inline bool safe_strto64(StringPiece str, int64_t* value) {
-  return safe_strto64(str.ToString(), value);
-}
-inline bool safe_strtou64(const char* str, uint64_t* value) {
-  return safe_strtou64(std::string(str), value);
-}
-inline bool safe_strtou64(StringPiece str, uint64_t* value) {
-  return safe_strtou64(str.ToString(), value);
-}
-
-PROTOBUF_EXPORT bool safe_strtof(const char* str, float* value);
-PROTOBUF_EXPORT bool safe_strtod(const char* str, double* value);
-inline bool safe_strtof(const std::string& str, float* value) {
-  return safe_strtof(str.c_str(), value);
-}
-inline bool safe_strtod(const std::string& str, double* value) {
-  return safe_strtod(str.c_str(), value);
-}
-inline bool safe_strtof(StringPiece str, float* value) {
-  return safe_strtof(str.ToString(), value);
-}
-inline bool safe_strtod(StringPiece str, double* value) {
-  return safe_strtod(str.ToString(), value);
-}
-
-// ----------------------------------------------------------------------
-// FastIntToBuffer()
-// FastHexToBuffer()
-// FastHex64ToBuffer()
-// FastHex32ToBuffer()
-// FastTimeToBuffer()
-//    These are intended for speed.  FastIntToBuffer() assumes the
-//    integer is non-negative.  FastHexToBuffer() puts output in
-//    hex rather than decimal.  FastTimeToBuffer() puts the output
-//    into RFC822 format.
-//
-//    FastHex64ToBuffer() puts a 64-bit unsigned value in hex-format,
-//    padded to exactly 16 bytes (plus one byte for '\0')
-//
-//    FastHex32ToBuffer() puts a 32-bit unsigned value in hex-format,
-//    padded to exactly 8 bytes (plus one byte for '\0')
-//
-//       All functions take the output buffer as an arg.
-//    They all return a pointer to the beginning of the output,
-//    which may not be the beginning of the input buffer.
-// ----------------------------------------------------------------------
-
-// Suggested buffer size for FastToBuffer functions.  Also works with
-// DoubleToBuffer() and FloatToBuffer().
-static const int kFastToBufferSize = 32;
-
-PROTOBUF_EXPORT char* FastInt32ToBuffer(int32_t i, char* buffer);
-PROTOBUF_EXPORT char* FastInt64ToBuffer(int64_t i, char* buffer);
-char* FastUInt32ToBuffer(uint32_t i, char* buffer);  // inline below
-char* FastUInt64ToBuffer(uint64_t i, char* buffer);  // inline below
-PROTOBUF_EXPORT char* FastHexToBuffer(int i, char* buffer);
-PROTOBUF_EXPORT char* FastHex64ToBuffer(uint64_t i, char* buffer);
-PROTOBUF_EXPORT char* FastHex32ToBuffer(uint32_t i, char* buffer);
-
-// at least 22 bytes long
-inline char* FastIntToBuffer(int i, char* buffer) {
-  return (sizeof(i) == 4 ?
-          FastInt32ToBuffer(i, buffer) : FastInt64ToBuffer(i, buffer));
-}
-inline char* FastUIntToBuffer(unsigned int i, char* buffer) {
-  return (sizeof(i) == 4 ?
-          FastUInt32ToBuffer(i, buffer) : FastUInt64ToBuffer(i, buffer));
-}
-inline char* FastLongToBuffer(long i, char* buffer) {
-  return (sizeof(i) == 4 ?
-          FastInt32ToBuffer(i, buffer) : FastInt64ToBuffer(i, buffer));
-}
-inline char* FastULongToBuffer(unsigned long i, char* buffer) {
-  return (sizeof(i) == 4 ?
-          FastUInt32ToBuffer(i, buffer) : FastUInt64ToBuffer(i, buffer));
-}
-
-// ----------------------------------------------------------------------
-// FastInt32ToBufferLeft()
-// FastUInt32ToBufferLeft()
-// FastInt64ToBufferLeft()
-// FastUInt64ToBufferLeft()
-//
-// Like the Fast*ToBuffer() functions above, these are intended for speed.
-// Unlike the Fast*ToBuffer() functions, however, these functions write
-// their output to the beginning of the buffer (hence the name, as the
-// output is left-aligned).  The caller is responsible for ensuring that
-// the buffer has enough space to hold the output.
-//
-// Returns a pointer to the end of the string (i.e. the null character
-// terminating the string).
-// ----------------------------------------------------------------------
-
-PROTOBUF_EXPORT char* FastInt32ToBufferLeft(int32_t i, char* buffer);
-PROTOBUF_EXPORT char* FastUInt32ToBufferLeft(uint32_t i, char* buffer);
-PROTOBUF_EXPORT char* FastInt64ToBufferLeft(int64_t i, char* buffer);
-PROTOBUF_EXPORT char* FastUInt64ToBufferLeft(uint64_t i, char* buffer);
-
-// Just define these in terms of the above.
-inline char* FastUInt32ToBuffer(uint32_t i, char* buffer) {
-  FastUInt32ToBufferLeft(i, buffer);
-  return buffer;
-}
-inline char* FastUInt64ToBuffer(uint64_t i, char* buffer) {
-  FastUInt64ToBufferLeft(i, buffer);
-  return buffer;
-}
-
-inline std::string SimpleBtoa(bool value) { return value ? "true" : "false"; }
-
-// ----------------------------------------------------------------------
-// SimpleItoa()
-//    Description: converts an integer to a string.
-//
-//    Return value: string
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT std::string SimpleItoa(int i);
-PROTOBUF_EXPORT std::string SimpleItoa(unsigned int i);
-PROTOBUF_EXPORT std::string SimpleItoa(long i);
-PROTOBUF_EXPORT std::string SimpleItoa(unsigned long i);
-PROTOBUF_EXPORT std::string SimpleItoa(long long i);
-PROTOBUF_EXPORT std::string SimpleItoa(unsigned long long i);
-
-// ----------------------------------------------------------------------
-// SimpleDtoa()
-// SimpleFtoa()
-// DoubleToBuffer()
-// FloatToBuffer()
-//    Description: converts a double or float to a string which, if
-//    passed to NoLocaleStrtod(), will produce the exact same original double
-//    (except in case of NaN; all NaNs are considered the same value).
-//    We try to keep the string short but it's not guaranteed to be as
-//    short as possible.
-//
-//    DoubleToBuffer() and FloatToBuffer() write the text to the given
-//    buffer and return it.  The buffer must be at least
-//    kDoubleToBufferSize bytes for doubles and kFloatToBufferSize
-//    bytes for floats.  kFastToBufferSize is also guaranteed to be large
-//    enough to hold either.
-//
-//    Return value: string
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT std::string SimpleDtoa(double value);
-PROTOBUF_EXPORT std::string SimpleFtoa(float value);
-
-PROTOBUF_EXPORT char* DoubleToBuffer(double i, char* buffer);
-PROTOBUF_EXPORT char* FloatToBuffer(float i, char* buffer);
-
-// In practice, doubles should never need more than 24 bytes and floats
-// should never need more than 14 (including null terminators), but we
-// overestimate to be safe.
-static const int kDoubleToBufferSize = 32;
-static const int kFloatToBufferSize = 24;
-
-namespace strings {
-
-enum PadSpec {
-  NO_PAD = 1,
-  ZERO_PAD_2,
-  ZERO_PAD_3,
-  ZERO_PAD_4,
-  ZERO_PAD_5,
-  ZERO_PAD_6,
-  ZERO_PAD_7,
-  ZERO_PAD_8,
-  ZERO_PAD_9,
-  ZERO_PAD_10,
-  ZERO_PAD_11,
-  ZERO_PAD_12,
-  ZERO_PAD_13,
-  ZERO_PAD_14,
-  ZERO_PAD_15,
-  ZERO_PAD_16,
-};
-
-struct Hex {
-  uint64_t value;
-  enum PadSpec spec;
-  template <class Int>
-  explicit Hex(Int v, PadSpec s = NO_PAD)
-      : spec(s) {
-    // Prevent sign-extension by casting integers to
-    // their unsigned counterparts.
-#ifdef LANG_CXX11
-    static_assert(
-        sizeof(v) == 1 || sizeof(v) == 2 || sizeof(v) == 4 || sizeof(v) == 8,
-        "Unknown integer type");
-#endif
-    value = sizeof(v) == 1 ? static_cast<uint8_t>(v)
-          : sizeof(v) == 2 ? static_cast<uint16_t>(v)
-          : sizeof(v) == 4 ? static_cast<uint32_t>(v)
-          : static_cast<uint64_t>(v);
-  }
-};
-
-struct PROTOBUF_EXPORT AlphaNum {
-  const char *piece_data_;  // move these to string_ref eventually
-  size_t piece_size_;       // move these to string_ref eventually
-
-  char digits[kFastToBufferSize];
-
-  // No bool ctor -- bools convert to an integral type.
-  // A bool ctor would also convert incoming pointers (bletch).
-
-  AlphaNum(int i32)
-      : piece_data_(digits),
-        piece_size_(FastInt32ToBufferLeft(i32, digits) - &digits[0]) {}
-  AlphaNum(unsigned int u32)
-      : piece_data_(digits),
-        piece_size_(FastUInt32ToBufferLeft(u32, digits) - &digits[0]) {}
-  AlphaNum(long long i64)
-      : piece_data_(digits),
-        piece_size_(FastInt64ToBufferLeft(i64, digits) - &digits[0]) {}
-  AlphaNum(unsigned long long u64)
-      : piece_data_(digits),
-        piece_size_(FastUInt64ToBufferLeft(u64, digits) - &digits[0]) {}
-
-  // Note: on some architectures, "long" is only 32 bits, not 64, but the
-  // performance hit of using FastInt64ToBufferLeft to handle 32-bit values
-  // is quite minor.
-  AlphaNum(long i64)
-      : piece_data_(digits),
-        piece_size_(FastInt64ToBufferLeft(i64, digits) - &digits[0]) {}
-  AlphaNum(unsigned long u64)
-      : piece_data_(digits),
-        piece_size_(FastUInt64ToBufferLeft(u64, digits) - &digits[0]) {}
-
-  AlphaNum(float f)
-    : piece_data_(digits), piece_size_(strlen(FloatToBuffer(f, digits))) {}
-  AlphaNum(double f)
-    : piece_data_(digits), piece_size_(strlen(DoubleToBuffer(f, digits))) {}
-
-  AlphaNum(Hex hex);
-
-  AlphaNum(const char* c_str)
-      : piece_data_(c_str), piece_size_(strlen(c_str)) {}
-  // TODO: Add a string_ref constructor, eventually
-  // AlphaNum(const StringPiece &pc) : piece(pc) {}
-
-  AlphaNum(const std::string& str)
-      : piece_data_(str.data()), piece_size_(str.size()) {}
-
-  AlphaNum(StringPiece str)
-      : piece_data_(str.data()), piece_size_(str.size()) {}
-
-  size_t size() const { return piece_size_; }
-  const char *data() const { return piece_data_; }
-
- private:
-  // Use ":" not ':'
-  AlphaNum(char c);  // NOLINT(runtime/explicit)
-
-  // Disallow copy and assign.
-  AlphaNum(const AlphaNum&);
-  void operator=(const AlphaNum&);
-};
-
-}  // namespace strings
-
-using strings::AlphaNum;
-
-// ----------------------------------------------------------------------
-// StrCat()
-//    This merges the given strings or numbers, with no delimiter.  This
-//    is designed to be the fastest possible way to construct a string out
-//    of a mix of raw C strings, strings, bool values,
-//    and numeric values.
-//
-//    Don't use this for user-visible strings.  The localization process
-//    works poorly on strings built up out of fragments.
-//
-//    For clarity and performance, don't use StrCat when appending to a
-//    string.  In particular, avoid using any of these (anti-)patterns:
-//      str.append(StrCat(...)
-//      str += StrCat(...)
-//      str = StrCat(str, ...)
-//    where the last is the worse, with the potential to change a loop
-//    from a linear time operation with O(1) dynamic allocations into a
-//    quadratic time operation with O(n) dynamic allocations.  StrAppend
-//    is a better choice than any of the above, subject to the restriction
-//    of StrAppend(&str, a, b, c, ...) that none of the a, b, c, ... may
-//    be a reference into str.
-// ----------------------------------------------------------------------
-
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b);
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b,
-                                   const AlphaNum& c);
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b,
-                                   const AlphaNum& c, const AlphaNum& d);
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b,
-                                   const AlphaNum& c, const AlphaNum& d,
-                                   const AlphaNum& e);
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b,
-                                   const AlphaNum& c, const AlphaNum& d,
-                                   const AlphaNum& e, const AlphaNum& f);
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b,
-                                   const AlphaNum& c, const AlphaNum& d,
-                                   const AlphaNum& e, const AlphaNum& f,
-                                   const AlphaNum& g);
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b,
-                                   const AlphaNum& c, const AlphaNum& d,
-                                   const AlphaNum& e, const AlphaNum& f,
-                                   const AlphaNum& g, const AlphaNum& h);
-PROTOBUF_EXPORT std::string StrCat(const AlphaNum& a, const AlphaNum& b,
-                                   const AlphaNum& c, const AlphaNum& d,
-                                   const AlphaNum& e, const AlphaNum& f,
-                                   const AlphaNum& g, const AlphaNum& h,
-                                   const AlphaNum& i);
-
-inline std::string StrCat(const AlphaNum& a) {
-  return std::string(a.data(), a.size());
-}
-
-// ----------------------------------------------------------------------
-// StrAppend()
-//    Same as above, but adds the output to the given string.
-//    WARNING: For speed, StrAppend does not try to check each of its input
-//    arguments to be sure that they are not a subset of the string being
-//    appended to.  That is, while this will work:
-//
-//    string s = "foo";
-//    s += s;
-//
-//    This will not (necessarily) work:
-//
-//    string s = "foo";
-//    StrAppend(&s, s);
-//
-//    Note: while StrCat supports appending up to 9 arguments, StrAppend
-//    is currently limited to 4.  That's rarely an issue except when
-//    automatically transforming StrCat to StrAppend, and can easily be
-//    worked around as consecutive calls to StrAppend are quite efficient.
-// ----------------------------------------------------------------------
-
-PROTOBUF_EXPORT void StrAppend(std::string* dest, const AlphaNum& a);
-PROTOBUF_EXPORT void StrAppend(std::string* dest, const AlphaNum& a,
-                               const AlphaNum& b);
-PROTOBUF_EXPORT void StrAppend(std::string* dest, const AlphaNum& a,
-                               const AlphaNum& b, const AlphaNum& c);
-PROTOBUF_EXPORT void StrAppend(std::string* dest, const AlphaNum& a,
-                               const AlphaNum& b, const AlphaNum& c,
-                               const AlphaNum& d);
-
-// ----------------------------------------------------------------------
-// Join()
-//    These methods concatenate a range of components into a C++ string, using
-//    the C-string "delim" as a separator between components.
-// ----------------------------------------------------------------------
-template <typename Iterator>
-void Join(Iterator start, Iterator end, const char* delim,
-          std::string* result) {
-  for (Iterator it = start; it != end; ++it) {
-    if (it != start) {
-      result->append(delim);
-    }
-    StrAppend(result, *it);
-  }
-}
-
-template <typename Range>
-std::string Join(const Range& components, const char* delim) {
-  std::string result;
-  Join(components.begin(), components.end(), delim, &result);
-  return result;
-}
-
-// ----------------------------------------------------------------------
-// ToHex()
-//    Return a lower-case hex string representation of the given integer.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT std::string ToHex(uint64_t num);
-
-// ----------------------------------------------------------------------
-// GlobalReplaceSubstring()
-//    Replaces all instances of a substring in a string.  Does nothing
-//    if 'substring' is empty.  Returns the number of replacements.
-//
-//    NOTE: The string pieces must not overlap s.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT int GlobalReplaceSubstring(const std::string& substring,
-                                           const std::string& replacement,
-                                           std::string* s);
-
-// ----------------------------------------------------------------------
-// Base64Unescape()
-//    Converts "src" which is encoded in Base64 to its binary equivalent and
-//    writes it to "dest". If src contains invalid characters, dest is cleared
-//    and the function returns false. Returns true on success.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT bool Base64Unescape(StringPiece src, std::string* dest);
-
-// ----------------------------------------------------------------------
-// WebSafeBase64Unescape()
-//    This is a variation of Base64Unescape which uses '-' instead of '+', and
-//    '_' instead of '/'. src is not null terminated, instead specify len. I
-//    recommend that slen<szdest, but we honor szdest anyway.
-//    RETURNS the length of dest, or -1 if src contains invalid chars.
-
-//    The variation that stores into a string clears the string first, and
-//    returns false (with dest empty) if src contains invalid chars; for
-//    this version src and dest must be different strings.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT int WebSafeBase64Unescape(const char* src, int slen, char* dest,
-                                          int szdest);
-PROTOBUF_EXPORT bool WebSafeBase64Unescape(StringPiece src, std::string* dest);
-
-// Return the length to use for the output buffer given to the base64 escape
-// routines. Make sure to use the same value for do_padding in both.
-// This function may return incorrect results if given input_len values that
-// are extremely high, which should happen rarely.
-PROTOBUF_EXPORT int CalculateBase64EscapedLen(int input_len, bool do_padding);
-// Use this version when calling Base64Escape without a do_padding arg.
-PROTOBUF_EXPORT int CalculateBase64EscapedLen(int input_len);
-
-// ----------------------------------------------------------------------
-// Base64Escape()
-// WebSafeBase64Escape()
-//    Encode "src" to "dest" using base64 encoding.
-//    src is not null terminated, instead specify len.
-//    'dest' should have at least CalculateBase64EscapedLen() length.
-//    RETURNS the length of dest.
-//    The WebSafe variation use '-' instead of '+' and '_' instead of '/'
-//    so that we can place the out in the URL or cookies without having
-//    to escape them.  It also has an extra parameter "do_padding",
-//    which when set to false will prevent padding with "=".
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT int Base64Escape(const unsigned char* src, int slen, char* dest,
-                                 int szdest);
-PROTOBUF_EXPORT int WebSafeBase64Escape(const unsigned char* src, int slen,
-                                        char* dest, int szdest,
-                                        bool do_padding);
-// Encode src into dest with padding.
-PROTOBUF_EXPORT void Base64Escape(StringPiece src, std::string* dest);
-// Encode src into dest web-safely without padding.
-PROTOBUF_EXPORT void WebSafeBase64Escape(StringPiece src, std::string* dest);
-// Encode src into dest web-safely with padding.
-PROTOBUF_EXPORT void WebSafeBase64EscapeWithPadding(StringPiece src,
-                                                    std::string* dest);
-
-PROTOBUF_EXPORT void Base64Escape(const unsigned char* src, int szsrc,
-                                  std::string* dest, bool do_padding);
-PROTOBUF_EXPORT void WebSafeBase64Escape(const unsigned char* src, int szsrc,
-                                         std::string* dest, bool do_padding);
-
-inline bool IsValidCodePoint(uint32_t code_point) {
-  return code_point < 0xD800 ||
-         (code_point >= 0xE000 && code_point <= 0x10FFFF);
-}
-
-static const int UTFmax = 4;
-// ----------------------------------------------------------------------
-// EncodeAsUTF8Char()
-//  Helper to append a Unicode code point to a string as UTF8, without bringing
-//  in any external dependencies. The output buffer must be as least 4 bytes
-//  large.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT int EncodeAsUTF8Char(uint32_t code_point, char* output);
-
-// ----------------------------------------------------------------------
-// UTF8FirstLetterNumBytes()
-//   Length of the first UTF-8 character.
-// ----------------------------------------------------------------------
-PROTOBUF_EXPORT int UTF8FirstLetterNumBytes(const char* src, int len);
-
-// From google3/third_party/absl/strings/escaping.h
-
-// ----------------------------------------------------------------------
-// CleanStringLineEndings()
-//   Clean up a multi-line string to conform to Unix line endings.
-//   Reads from src and appends to dst, so usually dst should be empty.
-//
-//   If there is no line ending at the end of a non-empty string, it can
-//   be added automatically.
-//
-//   Four different types of input are correctly handled:
-//
-//     - Unix/Linux files: line ending is LF: pass through unchanged
-//
-//     - DOS/Windows files: line ending is CRLF: convert to LF
-//
-//     - Legacy Mac files: line ending is CR: convert to LF
-//
-//     - Garbled files: random line endings: convert gracefully
-//                      lonely CR, lonely LF, CRLF: convert to LF
-//
-//   @param src The multi-line string to convert
-//   @param dst The converted string is appended to this string
-//   @param auto_end_last_line Automatically terminate the last line
-//
-//   Limitations:
-//
-//     This does not do the right thing for CRCRLF files created by
-//     broken programs that do another Unix->DOS conversion on files
-//     that are already in CRLF format.  For this, a two-pass approach
-//     brute-force would be needed that
-//
-//       (1) determines the presence of LF (first one is ok)
-//       (2) if yes, removes any CR, else convert every CR to LF
-PROTOBUF_EXPORT void CleanStringLineEndings(const std::string& src,
-                                            std::string* dst,
-                                            bool auto_end_last_line);
-
-// Same as above, but transforms the argument in place.
-PROTOBUF_EXPORT void CleanStringLineEndings(std::string* str,
-                                            bool auto_end_last_line);
-
-namespace strings {
-inline bool EndsWith(StringPiece text, StringPiece suffix) {
-  return suffix.empty() ||
-      (text.size() >= suffix.size() &&
-       memcmp(text.data() + (text.size() - suffix.size()), suffix.data(),
-              suffix.size()) == 0);
-}
-}  // namespace strings
-
-namespace internal {
-
-// A locale-independent version of the standard strtod(), which always
-// uses a dot as the decimal separator.
-double NoLocaleStrtod(const char* str, char** endptr);
-
-}  // namespace internal
-
-}  // namespace protobuf
-}  // namespace google
-
-#include <google/protobuf/port_undef.inc>
-
-#endif  // GOOGLE_PROTOBUF_STUBS_STRUTIL_H__
diff --git a/include/google/protobuf/stubs/template_util.h b/include/google/protobuf/stubs/template_util.h
deleted file mode 100644
index feef904bea..0000000000
--- a/include/google/protobuf/stubs/template_util.h
+++ /dev/null
@@ -1,138 +0,0 @@
-// Copyright 2005 Google Inc.
-// All rights reserved.
-//
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-// notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-// copyright notice, this list of conditions and the following disclaimer
-// in the documentation and/or other materials provided with the
-// distribution.
-//     * Neither the name of Google Inc. nor the names of its
-// contributors may be used to endorse or promote products derived from
-// this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-// ----
-// Author: lar@google.com (Laramie Leavitt)
-//
-// Template metaprogramming utility functions.
-//
-// This code is compiled directly on many platforms, including client
-// platforms like Windows, Mac, and embedded systems.  Before making
-// any changes here, make sure that you're not breaking any platforms.
-//
-//
-// The names chosen here reflect those used in tr1 and the boost::mpl
-// library, there are similar operations used in the Loki library as
-// well.  I prefer the boost names for 2 reasons:
-// 1.  I think that portions of the Boost libraries are more likely to
-// be included in the c++ standard.
-// 2.  It is not impossible that some of the boost libraries will be
-// included in our own build in the future.
-// Both of these outcomes means that we may be able to directly replace
-// some of these with boost equivalents.
-//
-#ifndef GOOGLE_PROTOBUF_TEMPLATE_UTIL_H_
-#define GOOGLE_PROTOBUF_TEMPLATE_UTIL_H_
-
-namespace google {
-namespace protobuf {
-namespace internal {
-
-// Types small_ and big_ are guaranteed such that sizeof(small_) <
-// sizeof(big_)
-typedef char small_;
-
-struct big_ {
-  char dummy[2];
-};
-
-// Identity metafunction.
-template <class T>
-struct identity_ {
-  typedef T type;
-};
-
-// integral_constant, defined in tr1, is a wrapper for an integer
-// value. We don't really need this generality; we could get away
-// with hardcoding the integer type to bool. We use the fully
-// general integer_constant for compatibility with tr1.
-
-template<class T, T v>
-struct integral_constant {
-  static const T value = v;
-  typedef T value_type;
-  typedef integral_constant<T, v> type;
-};
-
-template <class T, T v> const T integral_constant<T, v>::value;
-
-
-// Abbreviations: true_type and false_type are structs that represent boolean
-// true and false values. Also define the boost::mpl versions of those names,
-// true_ and false_.
-typedef integral_constant<bool, true>  true_type;
-typedef integral_constant<bool, false> false_type;
-typedef true_type  true_;
-typedef false_type false_;
-
-// if_ is a templatized conditional statement.
-// if_<cond, A, B> is a compile time evaluation of cond.
-// if_<>::type contains A if cond is true, B otherwise.
-template<bool cond, typename A, typename B>
-struct if_{
-  typedef A type;
-};
-
-template<typename A, typename B>
-struct if_<false, A, B> {
-  typedef B type;
-};
-
-
-// type_equals_ is a template type comparator, similar to Loki IsSameType.
-// type_equals_<A, B>::value is true iff "A" is the same type as "B".
-//
-// New code should prefer base::is_same, defined in base/type_traits.h.
-// It is functionally identical, but is_same is the standard spelling.
-template<typename A, typename B>
-struct type_equals_ : public false_ {
-};
-
-template<typename A>
-struct type_equals_<A, A> : public true_ {
-};
-
-// and_ is a template && operator.
-// and_<A, B>::value evaluates "A::value && B::value".
-template<typename A, typename B>
-struct and_ : public integral_constant<bool, (A::value && B::value)> {
-};
-
-// or_ is a template || operator.
-// or_<A, B>::value evaluates "A::value || B::value".
-template<typename A, typename B>
-struct or_ : public integral_constant<bool, (A::value || B::value)> {
-};
-
-
-}  // namespace internal
-}  // namespace protobuf
-}  // namespace google
-
-#endif  // GOOGLE_PROTOBUF_TEMPLATE_UTIL_H_