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diff --git a/boost/context/posix/protected_fixedsize_stack.hpp b/boost/context/posix/protected_fixedsize_stack.hpp
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+++ b/boost/context/posix/protected_fixedsize_stack.hpp
@@ -0,0 +1,112 @@
+
+//          Copyright Oliver Kowalke 2014.
+// Distributed under 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_CONTEXT_PROTECTED_FIXEDSIZE_H
+#define BOOST_CONTEXT_PROTECTED_FIXEDSIZE_H
+
+extern "C" {
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <unistd.h>
+}
+
+#include <cmath>
+#include <cstddef>
+#include <new>
+
+#include <boost/assert.hpp>
+#include <boost/config.hpp>
+
+#include <boost/context/detail/config.hpp>
+#include <boost/context/stack_context.hpp>
+#include <boost/context/stack_traits.hpp>
+
+#if defined(BOOST_USE_VALGRIND)
+#include <valgrind/valgrind.h>
+#endif
+
+#ifdef BOOST_HAS_ABI_HEADERS
+#  include BOOST_ABI_PREFIX
+#endif
+
+namespace boost {
+namespace context {
+
+template< typename traitsT >
+class basic_protected_fixedsize_stack {
+private:
+    std::size_t     size_;
+
+public:
+    typedef traitsT traits_type;
+
+    basic_protected_fixedsize_stack( std::size_t size = traits_type::default_size() ) :
+        size_( size) {
+        BOOST_ASSERT( traits_type::minimum_size() <= size_);
+        BOOST_ASSERT( traits_type::is_unbounded() || ( traits_type::maximum_size() >= size_) );
+    }
+
+    stack_context allocate() {
+        // page at bottom will be used as guard-page
+        const std::size_t pages(
+            static_cast< std::size_t >( 
+                std::floor(
+                    static_cast< float >( size_) / traits_type::page_size() ) ) );
+        BOOST_ASSERT_MSG( 2 <= pages, "at least two pages must fit into stack (one page is guard-page)");
+        const std::size_t size__( pages * traits_type::page_size() );
+        BOOST_ASSERT( 0 < size_ && 0 < size__);
+        BOOST_ASSERT( size__ <= size_);
+
+        // conform to POSIX.4 (POSIX.1b-1993, _POSIX_C_SOURCE=199309L)
+#if defined(MAP_ANON)
+        void * vp = ::mmap( 0, size__, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+#else
+        void * vp = ::mmap( 0, size__, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+#endif
+        if ( MAP_FAILED == vp) throw std::bad_alloc();
+
+        // conforming to POSIX.1-2001
+#if defined(BOOST_DISABLE_ASSERTS)
+        ::mprotect( vp, traits_type::page_size(), PROT_NONE);
+#else
+        const int result( ::mprotect( vp, traits_type::page_size(), PROT_NONE) );
+        BOOST_ASSERT( 0 == result);
+#endif
+
+        stack_context sctx;
+        sctx.size = size__;
+        sctx.sp = static_cast< char * >( vp) + sctx.size;
+#if defined(BOOST_USE_VALGRIND)
+        sctx.valgrind_stack_id = VALGRIND_STACK_REGISTER( sctx.sp, vp);
+#endif
+        return sctx;
+    }
+
+    void deallocate( stack_context & sctx) {
+        BOOST_ASSERT( sctx.sp);
+        BOOST_ASSERT( traits_type::minimum_size() <= sctx.size);
+        BOOST_ASSERT( traits_type::is_unbounded() || ( traits_type::maximum_size() >= sctx.size) );
+
+#if defined(BOOST_USE_VALGRIND)
+        VALGRIND_STACK_DEREGISTER( sctx.valgrind_stack_id);
+#endif
+
+        void * vp = static_cast< char * >( sctx.sp) - sctx.size;
+        // conform to POSIX.4 (POSIX.1b-1993, _POSIX_C_SOURCE=199309L)
+        ::munmap( vp, sctx.size);
+    }
+};
+
+typedef basic_protected_fixedsize_stack< stack_traits > protected_fixedsize_stack;
+
+}}
+
+#ifdef BOOST_HAS_ABI_HEADERS
+#  include BOOST_ABI_SUFFIX
+#endif
+
+#endif // BOOST_CONTEXT_PROTECTED_FIXEDSIZE_H