From e874029dd994ce1dd098a143aa06a0894da7b7de Mon Sep 17 00:00:00 2001
From: Jonathan Wakely <jwakely@redhat.com>
Date: Tue, 24 Jul 2018 21:49:10 +0100
Subject: [PATCH] PR libstdc++/86658 fix __niter_wrap to not copy invalid
 iterators

An output iterator passed as the unused first argument to __niter_wrap
might have already been invalidated, so don't copy it.

	PR libstdc++/86658
	* include/bits/stl_algobase.h (__niter_wrap<_Iterator>): Pass unused
	parameter by reference, to avoid copying invalid iterators.
	* testsuite/25_algorithms/copy/86658.cc: New test.

From-SVN: r262952
---
 libstdc++-v3/ChangeLog                        |  5 +++
 libstdc++-v3/include/bits/stl_algobase.h      |  2 +-
 .../testsuite/25_algorithms/copy/86658.cc     | 36 +++++++++++++++++++
 3 files changed, 42 insertions(+), 1 deletion(-)
 create mode 100644 libstdc++-v3/testsuite/25_algorithms/copy/86658.cc

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 2ed60c6c140..91c0f4c0afe 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,5 +1,10 @@
 2018-07-24  Jonathan Wakely  <jwakely@redhat.com>
 
+	PR libstdc++/86658
+	* include/bits/stl_algobase.h (__niter_wrap<_Iterator>): Pass unused
+	parameter by reference, to avoid copying invalid iterators.
+	* testsuite/25_algorithms/copy/86658.cc: New test.
+
 	* include/std/bit (__countl_zero, __countr_zero, __popcount): Use
 	local variables for number of digits instead of type aliases.
 	(__log2p1): Remove redundant branch also checked in __countl_zero.
diff --git a/libstdc++-v3/include/bits/stl_algobase.h b/libstdc++-v3/include/bits/stl_algobase.h
index f0130bc4123..b1ecd83ddb7 100644
--- a/libstdc++-v3/include/bits/stl_algobase.h
+++ b/libstdc++-v3/include/bits/stl_algobase.h
@@ -288,7 +288,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
   // No need to wrap, iterator already has the right type.
   template<typename _Iterator>
     inline _Iterator
-    __niter_wrap(_Iterator, _Iterator __res)
+    __niter_wrap(const _Iterator&, _Iterator __res)
     { return __res; }
 
   // All of these auxiliary structs serve two purposes.  (1) Replace
diff --git a/libstdc++-v3/testsuite/25_algorithms/copy/86658.cc b/libstdc++-v3/testsuite/25_algorithms/copy/86658.cc
new file mode 100644
index 00000000000..600747a823d
--- /dev/null
+++ b/libstdc++-v3/testsuite/25_algorithms/copy/86658.cc
@@ -0,0 +1,36 @@
+// Copyright (C) 2018 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 }
+
+#define _GLIBCXX_DEBUG
+#include <algorithm>
+#include <vector>
+
+void
+test01()
+{
+  int i[1] = { 1 };
+  std::vector<int> v(1);
+  std::copy(i, i+1, std::inserter(v, v.end()));
+}
+
+int
+main()
+{
+  test01();
+}
-- 
2.30.2