re PR libstdc++/57010 ([c++0x] priority_queue<>::pop() calls self-move-assignment operator)

2013-04-22  Paolo Carlini  <paolo.carlini@oracle.com>

	PR libstdc++/57010
	* include/bits/stl_heap.h (pop_heap): Avoid self move-assignment.
	* testsuite/25_algorithms/pop_heap/57010.cc: New.

From-SVN: r198125

3 files changed, 71 insertions, 4 deletions

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index ff36bc8..fdf739f 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,9 @@
+2013-04-22  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR libstdc++/57010
+	* include/bits/stl_heap.h (pop_heap): Avoid self move-assignment.
+	* testsuite/25_algorithms/pop_heap/57010.cc: New.
+
 2013-04-21  Evgeniy Stepanov  <eugenis@google.com>
 
 	* src/c++11/system_error.cc (generic_category_instance): Add
diff --git a/libstdc++-v3/include/bits/stl_heap.h b/libstdc++-v3/include/bits/stl_heap.h
index de09780..807a8cf 100644
--- a/libstdc++-v3/include/bits/stl_heap.h
+++ b/libstdc++-v3/include/bits/stl_heap.h
@@ -291,8 +291,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_valid_range(__first, __last);
       __glibcxx_requires_heap(__first, __last);
 
-      --__last;
-      std::__pop_heap(__first, __last, __last);
+      if (__last - __first > 1)
+	{
+	  --__last;
+	  std::__pop_heap(__first, __last, __last);
+	}
     }
 
   template<typename _RandomAccessIterator, typename _Distance,
@@ -363,8 +366,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       __glibcxx_requires_non_empty_range(__first, __last);
       __glibcxx_requires_heap_pred(__first, __last, __comp);
 
-      --__last;
-      std::__pop_heap(__first, __last, __last, __comp);
+      if (__last - __first > 1)
+	{
+	  --__last;
+	  std::__pop_heap(__first, __last, __last, __comp);
+	}
     }
 
   /**
diff --git a/libstdc++-v3/testsuite/25_algorithms/pop_heap/57010.cc b/libstdc++-v3/testsuite/25_algorithms/pop_heap/57010.cc
new file mode 100644
index 0000000..87eae48
--- /dev/null
+++ b/libstdc++-v3/testsuite/25_algorithms/pop_heap/57010.cc
@@ -0,0 +1,55 @@
+// Copyright (C) 2013 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++11" }
+
+#include <algorithm>
+#include <functional>
+#include <testsuite_hooks.h>
+#include <testsuite_iterators.h>
+#include <testsuite_rvalref.h>
+
+using __gnu_test::test_container;
+using __gnu_test::random_access_iterator_wrapper;
+using __gnu_test::rvalstruct;
+
+typedef test_container<rvalstruct, random_access_iterator_wrapper> container;
+
+void test01()
+{
+  {
+    rvalstruct makeheap[1];
+    container makecon(makeheap, makeheap + 1);
+
+    std::push_heap(makecon.begin(), makecon.end());
+    std::pop_heap(makecon.begin(), makecon.end());
+  }
+
+  {
+    rvalstruct makeheap[1];
+    container makecon(makeheap, makeheap + 1);
+
+    std::push_heap(makecon.begin(), makecon.end(), std::less<rvalstruct>());
+    std::pop_heap(makecon.begin(), makecon.end(), std::less<rvalstruct>());
+  }
+}
+
+int main()
+{
+  test01();
+  return 0;
+}