Index: libstdc++-v3/include/decimal/decimal.h
===================================================================
--- libstdc++-v3/include/decimal/decimal.h	(revision 189599)
+++ libstdc++-v3/include/decimal/decimal.h	(working copy)
@@ -288,7 +288,7 @@
   inline _Tp operator _Op(_Tp __rhs)		\
   {						\
     _Tp __tmp;					\
-    __tmp.__setval(0 _Op __rhs.__getval());	\
+    __tmp.__setval(_Op __rhs.__getval());	\
     return __tmp;				\
   }
 
Index: libstdc++-v3/testsuite/decimal/pr54036-1.cc
===================================================================
--- libstdc++-v3/testsuite/decimal/pr54036-1.cc	(revision 0)
+++ libstdc++-v3/testsuite/decimal/pr54036-1.cc	(revision 0)
@@ -0,0 +1,70 @@
+// Copyright (C) 2012 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-require-effective-target dfp }
+
+#include <decimal/decimal>
+#include <testsuite_hooks.h>
+
+using namespace std::decimal;
+
+decimal32
+__attribute__ ((noinline))
+my_nan32 (void)
+{
+  decimal32 z = 0;
+  decimal32 v = z/z;
+  return v;
+}
+
+decimal32
+__attribute__ ((noinline))
+my_inf32 (void)
+{
+  decimal32 o = 1;
+  decimal32 z = 0;
+  decimal32 v = o/z;
+  return v;
+}
+
+int
+main (void)
+{
+  decimal32 v;
+
+  v = my_nan32 ();
+
+  VERIFY (__builtin_isnand32 (v.__getval ()));
+  VERIFY (!__builtin_signbitd32 (v.__getval ()))
+
+  v = -v;
+
+  VERIFY (__builtin_isnand32 (v.__getval ()));
+  VERIFY (__builtin_signbitd32 (v.__getval ()))
+
+  v = my_inf32 ();
+
+  VERIFY (__builtin_isinfd32 (v.__getval ()));
+  VERIFY (!__builtin_signbitd32 (v.__getval ()))
+
+  v = -v;
+
+  VERIFY (__builtin_isinfd32 (v.__getval ()));
+  VERIFY (__builtin_signbitd32 (v.__getval ()))
+
+  return 0;
+}
Index: libstdc++-v3/testsuite/decimal/pr54036-2.cc
===================================================================
--- libstdc++-v3/testsuite/decimal/pr54036-2.cc	(revision 0)
+++ libstdc++-v3/testsuite/decimal/pr54036-2.cc	(revision 0)
@@ -0,0 +1,70 @@
+// Copyright (C) 2012 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-require-effective-target dfp }
+
+#include <decimal/decimal>
+#include <testsuite_hooks.h>
+
+using namespace std::decimal;
+
+decimal64
+__attribute__ ((noinline))
+my_nan64 (void)
+{
+  decimal64 z = 0;
+  decimal64 v = z/z;
+  return v;
+}
+
+decimal64
+__attribute__ ((noinline))
+my_inf64 (void)
+{
+  decimal64 o = 1;
+  decimal64 z = 0;
+  decimal64 v = o/z;
+  return v;
+}
+
+int
+main (void)
+{
+  decimal64 v;
+
+  v = my_nan64 ();
+
+  VERIFY (__builtin_isnand64 (v.__getval ()));
+  VERIFY (!__builtin_signbitd64 (v.__getval ()))
+
+  v = -v;
+
+  VERIFY (__builtin_isnand64 (v.__getval ()));
+  VERIFY (__builtin_signbitd64 (v.__getval ()))
+
+  v = my_inf64 ();
+
+  VERIFY (__builtin_isinfd64 (v.__getval ()));
+  VERIFY (!__builtin_signbitd64 (v.__getval ()))
+
+  v = -v;
+
+  VERIFY (__builtin_isinfd64 (v.__getval ()));
+  VERIFY (__builtin_signbitd64 (v.__getval ()))
+
+  return 0;
+}
Index: libstdc++-v3/testsuite/decimal/pr54036-3.cc
===================================================================
--- libstdc++-v3/testsuite/decimal/pr54036-3.cc	(revision 0)
+++ libstdc++-v3/testsuite/decimal/pr54036-3.cc	(revision 0)
@@ -0,0 +1,70 @@
+// Copyright (C) 2012 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-require-effective-target dfp }
+
+#include <decimal/decimal>
+#include <testsuite_hooks.h>
+
+using namespace std::decimal;
+
+decimal128
+__attribute__ ((noinline))
+my_nan128 (void)
+{
+  decimal128 z = 0;
+  decimal128 v = z/z;
+  return v;
+}
+
+decimal128
+__attribute__ ((noinline))
+my_inf128 (void)
+{
+  decimal128 o = 1;
+  decimal128 z = 0;
+  decimal128 v = o/z;
+  return v;
+}
+
+int
+main (void)
+{
+  decimal128 v;
+
+  v = my_nan128 ();
+
+  VERIFY (__builtin_isnand128 (v.__getval ()));
+  VERIFY (!__builtin_signbitd128 (v.__getval ()))
+
+  v = -v;
+
+  VERIFY (__builtin_isnand128 (v.__getval ()));
+  VERIFY (__builtin_signbitd128 (v.__getval ()))
+
+  v = my_inf128 ();
+
+  VERIFY (__builtin_isinfd128 (v.__getval ()));
+  VERIFY (!__builtin_signbitd128 (v.__getval ()))
+
+  v = -v;
+
+  VERIFY (__builtin_isinfd128 (v.__getval ()));
+  VERIFY (__builtin_signbitd128 (v.__getval ()))
+
+  return 0;
+}
