stl_tree.h (_Rb_tree_impl()): Restore _Node_allocator default init.

2017-06-12  François Dumont  <fdumont@gcc.gnu.org>

	* include/bits/stl_tree.h (_Rb_tree_impl()): Restore _Node_allocator
	default init.
	* testsuite/util/testsuite_allocator.h
	(__gnu_test::default_init_allocator<>) New.
	* testsuite/23_containers/set/allocator/default_init.cc: New.
	* testsuite/23_containers/map/allocator/default_init.cc: New.

From-SVN: r249136

libstdc++-v3/ChangeLog

@@ -1,3 +1,12 @@
+2017-06-12  François Dumont  <fdumont@gcc.gnu.org>
+
+	* include/bits/stl_tree.h (_Rb_tree_impl()): Restore _Node_allocator
+	default init.
+	* testsuite/util/testsuite_allocator.h
+	(__gnu_test::default_init_allocator<>) New.
+	* testsuite/23_containers/set/allocator/default_init.cc: New.
+	* testsuite/23_containers/map/allocator/default_init.cc: New.
+
 2017-06-12  Jonathan Wakely  <jwakely@redhat.com>
 
 	PR libstdc++/55917

libstdc++-v3/include/bits/stl_tree.h

@@ -572,11 +572,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
       _Node_allocator&
       _M_get_Node_allocator() _GLIBCXX_NOEXCEPT
-      { return *static_cast<_Node_allocator*>(&this->_M_impl); }
+      { return this->_M_impl; }
 
       const _Node_allocator&
       _M_get_Node_allocator() const _GLIBCXX_NOEXCEPT
-      { return *static_cast<const _Node_allocator*>(&this->_M_impl); }
+      { return this->_M_impl; }
 
       allocator_type
       get_allocator() const _GLIBCXX_NOEXCEPT
@@ -685,13 +685,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	{
 	  typedef _Rb_tree_key_compare<_Key_compare> _Base_key_compare;
 
-#if __cplusplus < 201103L
 	  _Rb_tree_impl()
+	    _GLIBCXX_NOEXCEPT_IF(
+		is_nothrow_default_constructible<_Node_allocator>::value
+		&& is_nothrow_default_constructible<_Base_key_compare>::value )
+	  : _Node_allocator()
 	  { }
-#else
-	  _Rb_tree_impl() = default;
-	  _Rb_tree_impl(_Rb_tree_impl&&) = default;
-#endif
 
 	  _Rb_tree_impl(const _Rb_tree_impl& __x)
 	  : _Node_allocator(_Alloc_traits::_S_select_on_copy(__x))
@@ -703,6 +702,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 	  : _Node_allocator(__a), _Base_key_compare(__comp)
 	  { }
 #else
+	  _Rb_tree_impl(_Rb_tree_impl&&) = default;
+
 	  _Rb_tree_impl(const _Key_compare& __comp, _Node_allocator&& __a)
 	  : _Node_allocator(std::move(__a)), _Base_key_compare(__comp)
 	  { }

libstdc++-v3/testsuite/23_containers/map/allocator/default_init.cc

@@ -0,0 +1,67 @@
+// Copyright (C) 2017 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-do run { target c++11 } }
+// { dg-options "-O0" }
+// { dg-xfail-run-if "PR c++/65816" { *-*-* } }
+
+#include <map>
+#include <testsuite_hooks.h>
+#include <testsuite_allocator.h>
+
+#include <ext/aligned_buffer.h>
+
+using T = int;
+
+using __gnu_test::default_init_allocator;
+
+void test01()
+{
+  typedef default_init_allocator<std::pair<const T, T>> alloc_type;
+  typedef std::map<T, T, std::less<T>, alloc_type> test_type;
+
+  __gnu_cxx::__aligned_buffer<test_type> buf;
+  __builtin_memset(buf._M_addr(), ~0, sizeof(test_type));
+
+  test_type *tmp = ::new(buf._M_addr()) test_type;
+
+  VERIFY( tmp->get_allocator().state == 0 );
+
+  tmp->~test_type();
+}
+
+void test02()
+{
+  typedef default_init_allocator<std::pair<const T, T>> alloc_type;
+  typedef std::map<T, T, std::less<T>, alloc_type> test_type;
+
+  __gnu_cxx::__aligned_buffer<test_type> buf;
+  __builtin_memset(buf._M_addr(), ~0, sizeof(test_type));
+
+  test_type *tmp = ::new(buf._M_addr()) test_type();
+
+  VERIFY( tmp->get_allocator().state == 0 );
+
+  tmp->~test_type();
+}
+
+int main()
+{
+  test01();
+  test02();
+  return 0;
+}

libstdc++-v3/testsuite/23_containers/set/allocator/default_init.cc

@@ -0,0 +1,67 @@
+// Copyright (C) 2017 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+// { dg-do run { target c++11 } }
+// { dg-options "-O0" }
+// { dg-xfail-run-if "PR c++/65816" { *-*-* } }
+
+#include <set>
+#include <testsuite_hooks.h>
+#include <testsuite_allocator.h>
+
+#include <ext/aligned_buffer.h>
+
+using T = int;
+
+using __gnu_test::default_init_allocator;
+
+void test01()
+{
+  typedef default_init_allocator<T> alloc_type;
+  typedef std::set<T, std::less<T>, alloc_type> test_type;
+
+  __gnu_cxx::__aligned_buffer<test_type> buf;
+  __builtin_memset(buf._M_addr(), ~0, sizeof(test_type));
+
+  test_type *tmp = ::new(buf._M_addr()) test_type;
+
+  VERIFY( tmp->get_allocator().state == 0 );
+
+  tmp->~test_type();
+}
+
+void test02()
+{
+  typedef default_init_allocator<T> alloc_type;
+  typedef std::set<T, std::less<T>, alloc_type> test_type;
+
+  __gnu_cxx::__aligned_buffer<test_type> buf;
+  __builtin_memset(buf._M_addr(), ~0, sizeof(test_type));
+
+  test_type *tmp = ::new(buf._M_addr()) test_type();
+
+  VERIFY( tmp->get_allocator().state == 0 );
+
+  tmp->~test_type();
+}
+
+int main()
+{
+  test01();
+  test02();
+  return 0;
+}

libstdc++-v3/testsuite/util/testsuite_allocator.h

@@ -508,6 +508,38 @@ namespace __gnu_test
     bool operator!=(const SimpleAllocator<T>&, const SimpleAllocator<U>&)
     { return false; }
 
+  template<typename T>
+    struct default_init_allocator
+    {
+      using value_type = T;
+
+      default_init_allocator() = default;
+
+      template<typename U>
+        default_init_allocator(const default_init_allocator<U>& a)
+	  : state(a.state)
+        { }
+
+      T*
+      allocate(std::size_t n)
+      { return std::allocator<T>().allocate(n); }
+
+      void
+      deallocate(T* p, std::size_t n)
+      { std::allocator<T>().deallocate(p, n); }
+
+      int state;
+    };
+
+  template<typename T, typename U>
+    bool operator==(const default_init_allocator<T>& t,
+		    const default_init_allocator<U>& u)
+    { return t.state == u.state; }
+
+  template<typename T, typename U>
+    bool operator!=(const default_init_allocator<T>& t,
+		    const default_init_allocator<U>& u)
+    { return !(t == u); }
 #endif
 
   template<typename Tp>