PR libstdc++/92267 fix ABI change in deque iterators

Defaulting the copy constructor on its first declaration made it change
from user-provided (and non-trivial) to implicitly-defined (and
trivial). This caused an ABI incompatibility between GCC 8 and GCC 9,
where functions taking a deque iterator disagree on the argument passing
convention.

Backport from mainline
2019-10-29  Jonathan Wakely  <jwakely@redhat.com>

	PR libstdc++/92267
	* include/bits/stl_deque.h (_Deque_iterator(const _Deque_iterator&)):
	Do not define as defaulted.
	* testsuite/23_containers/deque/types/92267.cc: New test.

From-SVN: r278614

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index ef28457065cd99a3ba0b0c2d38a2ffb3dd7e14f9..c793fe97722cde671d365b3f1897b21ba36c46d5 100644 (file)
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,13 @@
+2019-11-22  Jonathan Wakely  <jwakely@redhat.com>
+
+       Backport from mainline
+       2019-10-29  Jonathan Wakely  <jwakely@redhat.com>
+
+       PR libstdc++/92267
+       * include/bits/stl_deque.h (_Deque_iterator(const _Deque_iterator&)):
+       Do not define as defaulted.
+       * testsuite/23_containers/deque/types/92267.cc: New test.
+
 2019-10-28  John David Anglin  <danglin@gcc.gnu.org>
 
        * config/abi/post/hppa-linux-gnu/baseline_symbols.txt: Update.

diff --git a/libstdc++-v3/include/bits/stl_deque.h b/libstdc++-v3/include/bits/stl_deque.h
index 5c86efc0db2b586a8a1aec51645268f3e9998c3a..5a95399162fa188984d104ceade2122dc26b754b 100644 (file)
--- a/libstdc++-v3/include/bits/stl_deque.h
+++ b/libstdc++-v3/include/bits/stl_deque.h
@@ -158,13 +158,16 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
 #else
       // Conversion from iterator to const_iterator.
       template<typename _Iter,
-              typename = _Require<is_same<_Self, const_iterator>,
-                                  is_same<_Iter, iterator>>>
+              typename = _Require<is_same<_Self, const_iterator>,
+                                  is_same<_Iter, iterator>>>
        _Deque_iterator(const _Iter& __x) noexcept
        : _M_cur(__x._M_cur), _M_first(__x._M_first),
-         _M_last(__x._M_last), _M_node(__x._M_node) { }
+        _M_last(__x._M_last), _M_node(__x._M_node) { }
+
+      _Deque_iterator(const _Deque_iterator& __x) noexcept
+       : _M_cur(__x._M_cur), _M_first(__x._M_first),
+        _M_last(__x._M_last), _M_node(__x._M_node) { }
 
-      _Deque_iterator(const _Deque_iterator&) = default;
       _Deque_iterator& operator=(const _Deque_iterator&) = default;
 #endif
 

diff --git a/libstdc++-v3/testsuite/23_containers/deque/types/92267.cc b/libstdc++-v3/testsuite/23_containers/deque/types/92267.cc
new file mode 100644 (file)
index 0000000..cab8d25
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/deque/types/92267.cc
@@ -0,0 +1,27 @@
+// Copyright (C) 2019 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 compile { target c++11 } }
+
+#include <deque>
+
+using std::deque;
+using std::is_trivially_copy_constructible;
+
+// PR libstdc++/92267
+static_assert(!is_trivially_copy_constructible<deque<int>::iterator>::value);
+static_assert(!is_trivially_copy_constructible<deque<int>::const_iterator>::value);