diff --git a/include/boost/regex/config.hpp b/include/boost/regex/config.hpp
index 1b9e746d..cc783a0b 100644
--- a/include/boost/regex/config.hpp
+++ b/include/boost/regex/config.hpp
@@ -52,7 +52,7 @@
 #  include <vector>
 #  include <boost/config.hpp>
 #  include <boost/cstdint.hpp>
-#  include <boost/detail/allocator.hpp>
+#  include <boost/regex/config/allocator.hpp>
 #  include <boost/regex/config/cstring.hpp>
 #  include <boost/throw_exception.hpp>
 #  include <boost/scoped_ptr.hpp>
diff --git a/include/boost/regex/config/allocator.hpp b/include/boost/regex/config/allocator.hpp
new file mode 100644
index 00000000..458b6d29
--- /dev/null
+++ b/include/boost/regex/config/allocator.hpp
@@ -0,0 +1,281 @@
+/*
+ *
+ * Copyright (c) 2001
+ * Dr John Maddock
+ *
+ * Use, modification and distribution are subject to the 
+ * Boost Software License, Version 1.0. (See accompanying file 
+ * LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+ *
+ */
+
+#ifndef BOOST_DETAIL_ALLOCATOR_HPP
+#define BOOST_DETAIL_ALLOCATOR_HPP
+
+#include <boost/config.hpp>
+#include <cstdlib>
+#include <new>
+#include <assert.h>
+#if defined(BOOST_NO_STDC_NAMESPACE)
+namespace std{
+using ::ptrdiff_t;
+using ::size_t;
+}
+#endif
+
+// see if we have SGI alloc class:
+#if defined(BOOST_NO_STD_ALLOCATOR) && (defined(__SGI_STL_PORT) || defined(_STLPORT_VERSION) || defined(__GLIBCPP__) || defined(__STL_CONFIG_H))
+#  define BOOST_HAVE_SGI_ALLOCATOR
+#  include <memory>
+#  if defined(__SGI_STL_PORT) || defined(_STLPORT_VERSION)
+namespace boost{ namespace detail{
+   typedef std::__sgi_alloc alloc_type;
+}}
+#  else
+namespace boost{ namespace detail{
+   typedef std::alloc alloc_type;
+}}
+#  endif
+#endif
+
+
+namespace boost{ namespace detail{
+
+template <class T>
+void allocator_construct(T* p, const T& t)
+{ new (p) T(t); }
+
+template <class T>
+void allocator_destroy(T* p)
+{ 
+   (void)p; // warning suppression
+   p->~T(); 
+}
+
+} }
+
+#if !defined(BOOST_NO_STD_ALLOCATOR)
+
+#include <memory>
+
+#define BOOST_DEFAULT_ALLOCATOR(T) std::allocator< T >
+
+namespace boost{ namespace detail{
+
+template <class T, class A>
+struct rebind_allocator
+{
+   typedef typename A::template rebind<T> binder;
+   typedef typename binder::other type;
+};
+
+} // namespace detail
+} // namespace boost
+
+#elif !defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(__SUNPRO_CC)
+
+// no std::allocator, but the compiler supports the necessary syntax,
+// write our own allocator instead:
+
+#define BOOST_DEFAULT_ALLOCATOR(T) ::boost::detail::allocator< T >
+
+namespace boost{ namespace detail{
+
+template <class T>
+class allocator
+{
+public:
+
+   typedef T              value_type;
+   typedef value_type *   pointer;
+   typedef const T*       const_pointer;
+   typedef T&             reference;
+   typedef const T&       const_reference;
+   typedef std::size_t    size_type;
+   typedef std::ptrdiff_t difference_type;
+
+   template <class U>
+   struct rebind
+   {
+      typedef allocator<U> other;
+   };
+
+   allocator(){}
+   
+   template <class U>
+   allocator(const allocator<U>&){}
+
+   allocator(const allocator&){}
+
+   template <class U>
+   allocator& operator=(const allocator<U>&)
+   { return *this; }
+
+   ~allocator(){}
+
+   pointer address(reference x) { return &x; }
+
+   const_pointer address(const_reference x) const { return &x; }
+
+   pointer allocate(size_type n, const void* = 0) 
+   {
+      #ifdef BOOST_HAVE_SGI_ALLOCATOR
+      return n != 0 ?
+         reinterpret_cast<pointer>(alloc_type::allocate(n * sizeof(value_type)))
+         : 0;
+      #else
+      return n != 0 ?
+         reinterpret_cast<pointer>(::operator new(n * sizeof(value_type)))
+         : 0;
+      #endif
+   }
+
+   void deallocate(pointer p, size_type n) 
+   {
+      #ifdef BOOST_HAVE_SGI_ALLOCATOR
+      assert( (p == 0) == (n == 0) );
+      if (p != 0)
+         alloc_type::deallocate((void*)p, n);
+      #else
+      assert( (p == 0) == (n == 0) );
+      if (p != 0)
+         ::operator delete((void*)p);
+      #endif
+   }
+
+   size_type max_size() const
+   { return size_t(-1) / sizeof(value_type); }
+
+   void construct(pointer p, const T& val) const
+   { allocator_construct(p, val); }
+
+   void destroy(pointer p) const
+   { allocator_destroy(p); }
+};
+
+template <class T, class A>
+struct rebind_allocator
+{
+   typedef typename A::template rebind<T> binder;
+   typedef typename binder::other type;
+};
+
+} // namespace detail
+} // namespace boost
+
+#else
+
+// no std::allocator, use workaround version instead,
+// each allocator class must derive from a base class
+// that allocates blocks of bytes:
+
+#define BOOST_DEFAULT_ALLOCATOR(T) ::boost::detail::allocator_adapter<T, ::boost::detail::simple_alloc>
+
+namespace boost{ namespace detail{
+
+class simple_alloc
+{
+public:
+
+   typedef void           value_type;
+   typedef value_type *   pointer;
+   typedef const void*    const_pointer;
+   typedef std::size_t    size_type;
+   typedef std::ptrdiff_t difference_type;
+
+   simple_alloc(){}
+   simple_alloc(const simple_alloc&){}
+
+   ~simple_alloc(){}
+
+   pointer allocate(size_type n, const void* = 0) 
+   {
+      #ifdef BOOST_HAVE_SGI_ALLOCATOR
+      return n != 0 ?
+         reinterpret_cast<pointer>(alloc_type::allocate(n))
+         : 0;
+      #else
+      return n != 0 ?
+         reinterpret_cast<pointer>(::operator new(n))
+         : 0;
+      #endif
+   }
+
+   void deallocate(pointer p, size_type n) 
+   {
+      #ifdef BOOST_HAVE_SGI_ALLOCATOR
+      assert( (p == 0) == (n == 0) );
+      if (p != 0)
+         alloc_type::deallocate((void*)p, n);
+      #else
+      assert( (p == 0) == (n == 0) );
+      if (p != 0)
+         ::operator delete((void*)p);
+      #endif
+   }
+};
+
+template <class T, class Base>
+class allocator_adapter : public Base
+{
+public:
+
+   typedef T              value_type;
+   typedef value_type *   pointer;
+   typedef const T*       const_pointer;
+   typedef T&             reference;
+   typedef const T&       const_reference;
+   typedef size_t         size_type;
+   typedef std::ptrdiff_t difference_type;
+   typedef Base      base_type;
+
+   allocator_adapter(){}
+   allocator_adapter(const base_type& x) : Base(x){}
+   allocator_adapter& operator=(const base_type& x)
+   {
+      *(static_cast<base_type*>(this)) = x;
+      return *this;
+   }
+
+   ~allocator_adapter(){}
+
+   pointer address(reference x) { return &x; }
+
+   const_pointer address(const_reference x) const { return &x; }
+
+   pointer allocate(size_type n, const void* = 0) 
+   {
+      return n != 0 ?
+         reinterpret_cast<pointer>(base_type::allocate(n * sizeof(value_type)))
+         : 0;
+   }
+
+   void deallocate(pointer p, size_type n) 
+   {
+      assert( (p == 0) == (n == 0) );
+      if (p != 0)
+         static_cast<base_type*>(this)->deallocate((void*)p, n * sizeof(value_type));
+   }
+
+   size_type max_size() const
+   { return size_t(-1) / sizeof(value_type); }
+
+   void construct(pointer p, const T& val) const
+   { allocator_construct(p, val); }
+
+   void destroy(pointer p) const
+   { allocator_destroy(p); }
+};
+
+template <class T, class A>
+struct rebind_allocator
+{
+   typedef allocator_adapter<T, typename A::base_type> type;
+};
+
+} // namespace detail
+} // namespace boost
+
+#endif
+
+#endif // include guard
diff --git a/include/boost/regex/v3/regex_fwd.hpp b/include/boost/regex/v3/regex_fwd.hpp
index b163adb6..ef817f70 100644
--- a/include/boost/regex/v3/regex_fwd.hpp
+++ b/include/boost/regex/v3/regex_fwd.hpp
@@ -23,7 +23,7 @@
 #ifndef BOOST_REGEX_CONFIG_HPP
 #include <boost/config.hpp>
 #endif
-#include <boost/detail/allocator.hpp>
+#include <boost/regex/config/allocator.hpp>
 
 //
 // define BOOST_REGEX_NO_FWD if this
diff --git a/include/boost/regex/v4/regex_fwd.hpp b/include/boost/regex/v4/regex_fwd.hpp
index 214a9354..e5b437cc 100644
--- a/include/boost/regex/v4/regex_fwd.hpp
+++ b/include/boost/regex/v4/regex_fwd.hpp
@@ -23,7 +23,7 @@
 #ifndef BOOST_REGEX_CONFIG_HPP
 #include <boost/config.hpp>
 #endif
-#include <boost/detail/allocator.hpp>
+#include <boost/regex/config/allocator.hpp>
 
 //
 // define BOOST_REGEX_NO_FWD if this