1 files changed, 75 insertions, 0 deletions
diff --git a/libstdc++-v3/testsuite/26_numerics/valarray/87641.cc b/libstdc++-v3/testsuite/26_numerics/valarray/87641.cc
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+++ b/libstdc++-v3/testsuite/26_numerics/valarray/87641.cc
@@ -0,0 +1,75 @@
+// 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/>.
+
+#include <valarray>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  // PR libstdc++/87641
+  std::valarray<int> v1(3);
+  v1[0] = 1;
+  v1[1] = 2;
+  v1[2] = 3;
+  std::valarray< std::valarray<int> > v2(v1, 3);
+  std::valarray<int> v3 = v2.sum();
+  VERIFY( v3.size() == v1.size() );
+  VERIFY( v3[0] == 3 );
+  VERIFY( v3[1] == 6 );
+  VERIFY( v3[2] == 9 );
+}
+
+struct X
+{
+  X() : val(1) { }
+
+  X& operator+=(const X& x) { val += x.val; return *this; }
+  bool operator==(const X& x) { return val == x.val; }
+
+  int val;
+};
+
+void
+test02()
+{
+  std::valarray<X> v1(1);
+  VERIFY( v1.sum() == v1[0] );
+
+  std::valarray<X> v2(2);
+  VERIFY( v2.sum().val == 2 );
+}
+
+struct Y
+{
+  X& operator+=(const Y&) { throw 1; }
+};
+
+void
+test03()
+{
+  std::valarray<Y> v1(1);
+  (void) v1.sum(); // no addition performed for a single element
+}
+
+int
+main()
+{
+  test01();
+  test02();
+  test03();
+}