On 06/07/16 21:46 +0200, François Dumont wrote:
Don't you plan to add it to the testsuite ?
Done with the attached aptch.
On my side I rebase part of my patch to reorganize a little bit code.
I reintroduced _M_realloc_insert which isolates the code of
_M_insert_aux used when we need to reallocate memory. So _M_insert_aux
is used only when insertion can be done in place. It is a nice
replacement for _M_emplace_back_aux that have been removed. In most of
vector modifiers we start checking if we need to reallocate or not.
With this reorganization we don't check it several times. Moreover, as
soon as we reallocate we know that we don't need to do any temporary
copy so insert_vs_emplace.cc test04 has been adapted and we now have
no situation where emplace and insert are not equivalent.
* include/bits/stl_vector.h (push_back(const value_type&)): Forward
to _M_realloc_insert.
(insert(const_iterator, value_type&&)): Forward to _M_insert_rval.
(_M_realloc_insert): Declare new function.
(_M_emplace_back_aux): Remove definition.
* include/bits/vector.tcc (emplace_back(_Args...)):
Use _M_realloc_insert.
(insert(const_iterator, const value_type&)): Likewise.
(_M_insert_rval, _M_emplace_aux): Likewise.
(_M_emplace_back_aux): Remove declaration.
(_M_realloc_insert): Define.
* testsuite/23_containers/vector/modifiers/insert_vs_emplace.cc:
Adjust expected results for emplacing an lvalue with reallocation.
Tested under Linux x86_64.
Ok to commit ?
This is excellent work, thanks for doing it.
OK for trunk.
commit dd91c89f43bb79bc4e206824341536a234542c64
Author: redi <redi@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Fri Jul 8 16:35:10 2016 +0000
* testsuite/23_containers/vector/modifiers/insert/aliasing.cc: New.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@238169 138bc75d-0d04-0410-961f-82ee72b054a4
diff --git a/libstdc++-v3/testsuite/23_containers/vector/modifiers/insert/aliasing.cc b/libstdc++-v3/testsuite/23_containers/vector/modifiers/insert/aliasing.cc
new file mode 100644
index 0000000..2ef13b4
--- /dev/null
+++ b/libstdc++-v3/testsuite/23_containers/vector/modifiers/insert/aliasing.cc
@@ -0,0 +1,79 @@
+// 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/>.
+
+// { dg-options "-std=gnu++14" }
+
+#include <vector>
+#include <memory>
+#include <testsuite_hooks.h>
+
+// See https://gcc.gnu.org/ml/libstdc++/2016-07/msg00008.html for background.
+
+struct T
+{
+ T(int v = 0) : value(v) { }
+ T(const T& t);
+ T& operator=(const T& t);
+ void make_child() { child = std::make_unique<T>(value + 10); }
+ std::unique_ptr<T> child;
+ int value;
+};
+
+T::T(const T& t) : value(t.value)
+{
+ if (t.child)
+ child.reset(new T(*t.child));
+}
+
+T& T::operator=(const T& t)
+{
+ value = t.value;
+ if (t.child)
+ {
+ if (child)
+ *child = *t.child;
+ else
+ child.reset(new T(*t.child));
+ }
+ else
+ child.reset();
+ return *this;
+}
+
+void
+test01()
+{
+ std::vector<T> v;
+ v.reserve(3);
+ v.push_back(T(1));
+ v.back().make_child();
+ v.push_back(T(2));
+ v.back().make_child();
+
+ VERIFY(v[1].child->value == 12);
+ VERIFY(v[1].child->child == nullptr);
+
+ v.insert(v.begin(), *v[1].child);
+
+ VERIFY(v[0].value == 12);
+ VERIFY(v[0].child == nullptr);
+}
+
+int main()
+{
+ test01();
+}
