Add constexpr to <iterator> and <array> for C++17

	* include/bits/c++config (_GLIBCXX17_CONSTEXPR): Define.
	* include/bits/range_access.h (begin, end, rbegin, rend, crbegin)
	(crend): Add _GLIBCXX17_CONSTEXPR as per P0031R0.
	* include/bits/stl_iterator.h (reverse_iterator, move_iterator)
	(__make_reverse_iterator, make_reverse_iterator, make_move_iterator):
	Likewise.
	* include/bits/stl_iterator_base_funcs.h (__distance, __advance): Add
	_GLIBCXX14_CONSTEXPR.
	(distance, advance, next, prev): Add _GLIBCXX17_CONSTEXPR.
	* include/std/array (array::begin, array::end, array::rbegin)
	(array::rend, array::cbegin, array:cend, array::crbegin)
	(array::crend, array::operator[], array::at, array::front)
	(array::back, array::data): Likewise.
	* testsuite/24_iterators/headers/iterator/range_access.cc: Replace
	with separate tests for C++11, C++14, and C++17.
	* testsuite/24_iterators/headers/iterator/range_access_c++11.cc: New.
	* testsuite/24_iterators/headers/iterator/range_access_c++14.cc: New.
	* testsuite/24_iterators/headers/iterator/range_access_c++17.cc: New.

From-SVN: r239690

libstdc++-v3/ChangeLog

+2016-08-23  Jonathan Wakely  <jwakely@redhat.com>
+
+	* include/bits/c++config (_GLIBCXX17_CONSTEXPR): Define.
+	* include/bits/range_access.h (begin, end, rbegin, rend, crbegin)
+	(crend): Add _GLIBCXX17_CONSTEXPR as per P0031R0.
+	* include/bits/stl_iterator.h (reverse_iterator, move_iterator)
+	(__make_reverse_iterator, make_reverse_iterator, make_move_iterator):
+	Likewise.
+	* include/bits/stl_iterator_base_funcs.h (__distance, __advance): Add
+	_GLIBCXX14_CONSTEXPR.
+	(distance, advance, next, prev): Add _GLIBCXX17_CONSTEXPR.
+	* include/std/array (array::begin, array::end, array::rbegin)
+	(array::rend, array::cbegin, array:cend, array::crbegin)
+	(array::crend, array::operator[], array::at, array::front)
+	(array::back, array::data): Likewise.
+	* testsuite/24_iterators/headers/iterator/range_access.cc: Replace
+	with separate tests for C++11, C++14, and C++17.
+	* testsuite/24_iterators/headers/iterator/range_access_c++11.cc: New.
+	* testsuite/24_iterators/headers/iterator/range_access_c++14.cc: New.
+	* testsuite/24_iterators/headers/iterator/range_access_c++17.cc: New.
+
 2016-08-22  Tim Shen  <timshen@google.com>
 
 	Split _M_dfs() into smaller functions.

libstdc++-v3/include/bits/c++config

@@ -111,6 +111,14 @@
 # endif
 #endif
 
+#ifndef _GLIBCXX17_CONSTEXPR
+# if __cplusplus > 201402L
+#  define _GLIBCXX17_CONSTEXPR constexpr
+# else
+#  define _GLIBCXX17_CONSTEXPR
+# endif
+#endif
+
 // Macro for noexcept, to support in mixed 03/0x mode.
 #ifndef _GLIBCXX_NOEXCEPT
 # if __cplusplus >= 201103L

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

@@ -48,7 +48,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     begin(_Container& __cont) -> decltype(__cont.begin())
     { return __cont.begin(); }
 
@@ -58,7 +58,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     begin(const _Container& __cont) -> decltype(__cont.begin())
     { return __cont.begin(); }
 
@@ -68,7 +68,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     end(_Container& __cont) -> decltype(__cont.end())
     { return __cont.end(); }
 
@@ -78,7 +78,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     end(const _Container& __cont) -> decltype(__cont.end())
     { return __cont.end(); }
 
@@ -138,7 +138,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     rbegin(_Container& __cont) -> decltype(__cont.rbegin())
     { return __cont.rbegin(); }
 
@@ -148,7 +148,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     rbegin(const _Container& __cont) -> decltype(__cont.rbegin())
     { return __cont.rbegin(); }
 
@@ -158,7 +158,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     rend(_Container& __cont) -> decltype(__cont.rend())
     { return __cont.rend(); }
 
@@ -168,7 +168,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     rend(const _Container& __cont) -> decltype(__cont.rend())
     { return __cont.rend(); }
 
@@ -178,7 +178,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __arr  Array.
    */
   template<typename _Tp, size_t _Nm>
-    inline reverse_iterator<_Tp*>
+    inline _GLIBCXX17_CONSTEXPR reverse_iterator<_Tp*>
     rbegin(_Tp (&__arr)[_Nm])
     { return reverse_iterator<_Tp*>(__arr + _Nm); }
 
@@ -188,7 +188,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __arr  Array.
    */
   template<typename _Tp, size_t _Nm>
-    inline reverse_iterator<_Tp*>
+    inline _GLIBCXX17_CONSTEXPR reverse_iterator<_Tp*>
     rend(_Tp (&__arr)[_Nm])
     { return reverse_iterator<_Tp*>(__arr); }
 
@@ -198,7 +198,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __il  initializer_list.
    */
   template<typename _Tp>
-    inline reverse_iterator<const _Tp*>
+    inline _GLIBCXX17_CONSTEXPR reverse_iterator<const _Tp*>
     rbegin(initializer_list<_Tp> __il)
     { return reverse_iterator<const _Tp*>(__il.end()); }
 
@@ -208,7 +208,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __il  initializer_list.
    */
   template<typename _Tp>
-    inline reverse_iterator<const _Tp*>
+    inline _GLIBCXX17_CONSTEXPR reverse_iterator<const _Tp*>
     rend(initializer_list<_Tp> __il)
     { return reverse_iterator<const _Tp*>(__il.begin()); }
 
@@ -218,7 +218,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     crbegin(const _Container& __cont) -> decltype(std::rbegin(__cont))
     { return std::rbegin(__cont); }
 
@@ -228,7 +228,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  @param  __cont  Container.
    */
   template<typename _Container>
-    inline auto
+    inline _GLIBCXX17_CONSTEXPR auto
     crend(const _Container& __cont) -> decltype(std::rend(__cont))
     { return std::rend(__cont); }
 

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

@@ -75,7 +75,8 @@ _GLIBCXX_END_NAMESPACE_CONTAINER
 _GLIBCXX_BEGIN_NAMESPACE_VERSION
 
   template<typename _InputIterator>
-    inline typename iterator_traits<_InputIterator>::difference_type
+    inline _GLIBCXX14_CONSTEXPR
+    typename iterator_traits<_InputIterator>::difference_type
     __distance(_InputIterator __first, _InputIterator __last,
                input_iterator_tag)
     {
@@ -92,7 +93,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _RandomAccessIterator>
-    inline typename iterator_traits<_RandomAccessIterator>::difference_type
+    inline _GLIBCXX14_CONSTEXPR
+    typename iterator_traits<_RandomAccessIterator>::difference_type
     __distance(_RandomAccessIterator __first, _RandomAccessIterator __last,
                random_access_iterator_tag)
     {
@@ -131,7 +133,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  and are constant time.  For other %iterator classes they are linear time.
   */
   template<typename _InputIterator>
-    inline typename iterator_traits<_InputIterator>::difference_type
+    inline _GLIBCXX17_CONSTEXPR
+    typename iterator_traits<_InputIterator>::difference_type
     distance(_InputIterator __first, _InputIterator __last)
     {
       // concept requirements -- taken care of in __distance
@@ -140,7 +143,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _InputIterator, typename _Distance>
-    inline void
+    inline _GLIBCXX14_CONSTEXPR void
     __advance(_InputIterator& __i, _Distance __n, input_iterator_tag)
     {
       // concept requirements
@@ -151,7 +154,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _BidirectionalIterator, typename _Distance>
-    inline void
+    inline _GLIBCXX14_CONSTEXPR void
     __advance(_BidirectionalIterator& __i, _Distance __n,
 	      bidirectional_iterator_tag)
     {
@@ -167,7 +170,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _RandomAccessIterator, typename _Distance>
-    inline void
+    inline _GLIBCXX14_CONSTEXPR void
     __advance(_RandomAccessIterator& __i, _Distance __n,
               random_access_iterator_tag)
     {
@@ -190,7 +193,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
    *  and are constant time.  For other %iterator classes they are linear time.
   */
   template<typename _InputIterator, typename _Distance>
-    inline void
+    inline _GLIBCXX17_CONSTEXPR void
     advance(_InputIterator& __i, _Distance __n)
     {
       // concept requirements -- taken care of in __advance
@@ -201,7 +204,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 #if __cplusplus >= 201103L
 
   template<typename _ForwardIterator>
-    inline _ForwardIterator
+    inline _GLIBCXX17_CONSTEXPR _ForwardIterator
     next(_ForwardIterator __x, typename
 	 iterator_traits<_ForwardIterator>::difference_type __n = 1)
     {
@@ -213,7 +216,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     }
 
   template<typename _BidirectionalIterator>
-    inline _BidirectionalIterator
+    inline _GLIBCXX17_CONSTEXPR _BidirectionalIterator
     prev(_BidirectionalIterator __x, typename
 	 iterator_traits<_BidirectionalIterator>::difference_type __n = 1) 
     {

libstdc++-v3/include/std/array

@@ -122,51 +122,51 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       { std::swap_ranges(begin(), end(), __other.begin()); }
 
       // Iterators.
-      iterator
+      _GLIBCXX17_CONSTEXPR iterator
       begin() noexcept
       { return iterator(data()); }
 
-      const_iterator
+      _GLIBCXX17_CONSTEXPR const_iterator
       begin() const noexcept
       { return const_iterator(data()); }
 
-      iterator
+      _GLIBCXX17_CONSTEXPR iterator
       end() noexcept
       { return iterator(data() + _Nm); }
 
-      const_iterator
+      _GLIBCXX17_CONSTEXPR const_iterator
       end() const noexcept
       { return const_iterator(data() + _Nm); }
 
-      reverse_iterator
+      _GLIBCXX17_CONSTEXPR reverse_iterator
       rbegin() noexcept
       { return reverse_iterator(end()); }
 
-      const_reverse_iterator
+      _GLIBCXX17_CONSTEXPR const_reverse_iterator
       rbegin() const noexcept
       { return const_reverse_iterator(end()); }
 
-      reverse_iterator
+      _GLIBCXX17_CONSTEXPR reverse_iterator
       rend() noexcept
       { return reverse_iterator(begin()); }
 
-      const_reverse_iterator
+      _GLIBCXX17_CONSTEXPR const_reverse_iterator
       rend() const noexcept
       { return const_reverse_iterator(begin()); }
 
-      const_iterator
+      _GLIBCXX17_CONSTEXPR const_iterator
       cbegin() const noexcept
       { return const_iterator(data()); }
 
-      const_iterator
+      _GLIBCXX17_CONSTEXPR const_iterator
       cend() const noexcept
       { return const_iterator(data() + _Nm); }
 
-      const_reverse_iterator
+      _GLIBCXX17_CONSTEXPR const_reverse_iterator
       crbegin() const noexcept
       { return const_reverse_iterator(end()); }
 
-      const_reverse_iterator
+      _GLIBCXX17_CONSTEXPR const_reverse_iterator
       crend() const noexcept
       { return const_reverse_iterator(begin()); }
 
@@ -181,7 +181,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       empty() const noexcept { return size() == 0; }
 
       // Element access.
-      reference
+      _GLIBCXX17_CONSTEXPR reference
       operator[](size_type __n) noexcept
       { return _AT_Type::_S_ref(_M_elems, __n); }
 
@@ -189,7 +189,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       operator[](size_type __n) const noexcept
       { return _AT_Type::_S_ref(_M_elems, __n); }
 
-      reference
+      _GLIBCXX17_CONSTEXPR reference
       at(size_type __n)
       {
 	if (__n >= _Nm)
@@ -211,7 +211,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 	     _AT_Type::_S_ref(_M_elems, 0));
       }
 
-      reference
+      _GLIBCXX17_CONSTEXPR reference
       front() noexcept
       { return *begin(); }
 
@@ -219,7 +219,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       front() const noexcept
       { return _AT_Type::_S_ref(_M_elems, 0); }
 
-      reference
+      _GLIBCXX17_CONSTEXPR reference
       back() noexcept
       { return _Nm ? *(end() - 1) : *end(); }
 
@@ -230,11 +230,11 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
  	           : _AT_Type::_S_ref(_M_elems, 0);
       }
 
-      pointer
+      _GLIBCXX17_CONSTEXPR pointer
       data() noexcept
       { return _AT_Type::_S_ptr(_M_elems); }
 
-      const_pointer
+      _GLIBCXX17_CONSTEXPR const_pointer
       data() const noexcept
       { return _AT_Type::_S_ptr(_M_elems); }
     };

libstdc++-v3/testsuite/24_iterators/headers/iterator/range_access.cc → libstdc++-v3/testsuite/24_iterators/headers/iterator/range_access_c++11.cc

-// { dg-do compile { target c++11 } }
+// { dg-options "-std=gnu++11" }
+// { dg-do compile }
 
 // Copyright (C) 2010-2016 Free Software Foundation, Inc.
 //
@@ -27,11 +28,6 @@ namespace std
   template<class C> auto end(C& c) -> decltype(c.end());
   template<class C> auto end(const C& c) -> decltype(c.end());
 
-#if __cplusplus >= 201402L
-  template<class T, size_t N> constexpr T* begin(T (&array)[N]);
-  template<class T, size_t N> constexpr T* end(T (&array)[N]);
-#else
   template<class T, size_t N> T* begin(T (&array)[N]);
   template<class T, size_t N> T* end(T (&array)[N]);
-#endif
 }

libstdc++-v3/testsuite/24_iterators/headers/iterator/range_access_c++14.cc

+// { dg-options "-std=gnu++14" }
+// { dg-do compile }
+
+// Copyright (C) 2016 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/>.
+
+#include <iterator>
+
+namespace std
+{
+  template<class C> auto begin(C& c) -> decltype(c.begin());
+  template<class C> auto begin(const C& c) -> decltype(c.begin());
+
+  template<class C> auto end(C& c) -> decltype(c.end());
+  template<class C> auto end(const C& c) -> decltype(c.end());
+
+  template<class T, size_t N> constexpr T* begin(T (&array)[N]);
+  template<class T, size_t N> constexpr T* end(T (&array)[N]);
+
+  template<class C> auto cbegin(const C& c) -> decltype(c.begin());
+  template<class C> auto cend(const C& c) -> decltype(c.end());
+
+  template<class C> auto rbegin(C& c) -> decltype(c.rbegin());
+  template<class C> auto rbegin(const C& c) -> decltype(c.rbegin());
+
+  template<class C> auto rend(C& c) -> decltype(c.rend());
+  template<class C> auto rend(const C& c) -> decltype(c.rend());
+
+  template<class T, size_t N>
+    reverse_iterator<T*> rbegin(T (&array)[N]);
+  template<class T, size_t N>
+    reverse_iterator<T*> rend(T (&array)[N]);
+
+  template<class E>
+    reverse_iterator<const E*> rbegin(initializer_list<E>);
+  template<class E>
+    reverse_iterator<const E*> rend(initializer_list<E>);
+
+  template<class C>
+    auto crbegin(const C& c) -> decltype(std::rbegin(c));
+  template<class C>
+    auto cend(const C& c) -> decltype(std::rend(c));
+}

libstdc++-v3/testsuite/24_iterators/headers/iterator/range_access_c++17.cc

+// { dg-options "-std=gnu++17" }
+// { dg-do compile }
+
+// Copyright (C) 2016 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/>.
+
+#include <iterator>
+
+namespace std
+{
+  template<class C> constexpr auto begin(C& c) -> decltype(c.begin());
+  template<class C> constexpr auto begin(const C& c) -> decltype(c.begin());
+
+  template<class C> constexpr auto end(C& c) -> decltype(c.end());
+  template<class C> constexpr auto end(const C& c) -> decltype(c.end());
+
+  template<class T, size_t N> constexpr T* begin(T (&array)[N]);
+  template<class T, size_t N> constexpr T* end(T (&array)[N]);
+
+  template<class C> constexpr auto cbegin(const C& c) -> decltype(c.begin());
+  template<class C> constexpr auto cend(const C& c) -> decltype(c.end());
+
+  template<class C> constexpr auto rbegin(C& c) -> decltype(c.rbegin());
+  template<class C> constexpr auto rbegin(const C& c) -> decltype(c.rbegin());
+
+  template<class C> constexpr auto rend(C& c) -> decltype(c.rend());
+  template<class C> constexpr auto rend(const C& c) -> decltype(c.rend());
+
+  template<class T, size_t N>
+    constexpr reverse_iterator<T*> rbegin(T (&array)[N]);
+  template<class T, size_t N>
+    constexpr reverse_iterator<T*> rend(T (&array)[N]);
+
+  template<class E>
+    constexpr reverse_iterator<const E*> rbegin(initializer_list<E>);
+  template<class E>
+    constexpr reverse_iterator<const E*> rend(initializer_list<E>);
+
+  template<class C>
+    constexpr auto crbegin(const C& c) -> decltype(std::rbegin(c));
+  template<class C>
+    constexpr auto cend(const C& c) -> decltype(std::rend(c));
+}

libstdc++-v3/testsuite/ext/profile/mutex_extensions_neg.cc

@@ -25,7 +25,7 @@
 
 #include <vector>
 
-// { dg-error "multiple inlined namespaces" "" { target *-*-* } 324 }
+// { dg-error "multiple inlined namespaces" "" { target *-*-* } 332 }
 
 // "template argument 1 is invalid"
 // { dg-prune-output "tuple:993" }