diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index c7ec6f58921..5b6e4e2a71f 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,10 @@
+2009-05-06  Johannes Singler  <singler@ira.uka.de>
+
+        PR libstdc++/39546
+        * include/parallel/algo.h (find_switch):
+        Parametrize binder2nd with const T& instead of T.
+        * testsuite/25_algorithms/find/39546.cc: new test case
+
 2009-05-06  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	Revert:
diff --git a/libstdc++-v3/include/parallel/algo.h b/libstdc++-v3/include/parallel/algo.h
index 59106b2d364..a0fbd8d91d6 100644
--- a/libstdc++-v3/include/parallel/algo.h
+++ b/libstdc++-v3/include/parallel/algo.h
@@ -149,8 +149,8 @@ namespace __parallel
 
       if (_GLIBCXX_PARALLEL_CONDITION(true))
         {
-          binder2nd<__gnu_parallel::equal_to<value_type, T> >
-            comp(__gnu_parallel::equal_to<value_type, T>(), val);
+          binder2nd<__gnu_parallel::equal_to<value_type, const T&> >
+            comp(__gnu_parallel::equal_to<value_type, const T&>(), val);
           return __gnu_parallel::find_template(begin, end, begin, comp,
                                                __gnu_parallel::
                                                find_if_selector()).first;
diff --git a/libstdc++-v3/testsuite/25_algorithms/find/39546.cc b/libstdc++-v3/testsuite/25_algorithms/find/39546.cc
new file mode 100644
index 00000000000..b83a8553436
--- /dev/null
+++ b/libstdc++-v3/testsuite/25_algorithms/find/39546.cc
@@ -0,0 +1,43 @@
+// Copyright (C) 2009 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/>.
+
+// 25.3.1 algorithms, find()
+
+#include <vector>
+#include <string>
+#include <algorithm>
+#include <testsuite_hooks.h>
+
+// libstdc++/39546
+void
+test01()
+{
+  bool test __attribute__((unused)) = true;
+
+  std::vector<std::string> dict;
+  dict.push_back("one");
+  dict.push_back("two");
+  dict.push_back("three");
+
+  VERIFY( std::find(dict.begin(), dict.end(), "two") == dict.begin() + 1 );
+}
+
+int
+main()
+{
+  test01();
+}