re PR libstdc++/50880 (__complex_acosh() picks wrong complex branch)

2011-10-27  Richard B. Kreckel  <kreckel@ginac.de>
	    Paolo Carlini  <paolo.carlini@oracle.com>

	PR libstdc++/50880
	* include/std/complex (__complex_acosh): Fix for __z.real() < 0.
	* include/tr1/complex (__complex_acosh): Likewise.
	* testsuite/26_numerics/complex/50880.cc: New.
	* testsuite/tr1/8_c_compatibility/complex/50880.cc: Likewise.

Co-Authored-By: Paolo Carlini <paolo.carlini@oracle.com>

From-SVN: r180563

libstdc++-v3/ChangeLog

+2011-10-27  Richard B. Kreckel  <kreckel@ginac.de>
+	    Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR libstdc++/50880
+	* include/std/complex (__complex_acosh): Fix for __z.real() < 0.
+	* include/tr1/complex (__complex_acosh): Likewise.
+	* testsuite/26_numerics/complex/50880.cc: New.
+	* testsuite/tr1/8_c_compatibility/complex/50880.cc: Likewise.
+
 2011-10-27  Jonathan Wakely  <jwakely.gcc@gmail.com>
 
 	PR libstdc++/50862

libstdc++-v3/include/std/complex

@@ -1690,6 +1690,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 			    * (__z.real() + __z.imag()) - _Tp(1.0),
 			    _Tp(2.0) * __z.real() * __z.imag());
       __t = std::sqrt(__t);
+      if (__z.real() < _Tp(-0.0))
+	__t = -__t;
 
       return std::log(__t + __z);
     }

libstdc++-v3/include/tr1/complex

@@ -189,6 +189,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
 			    * (__z.real() + __z.imag()) - _Tp(1.0),
 			    _Tp(2.0) * __z.real() * __z.imag());
       __t = std::sqrt(__t);
+      if (__z.real() < _Tp(-0.0))
+	__t = -__t;
 
       return std::log(__t + __z);
     }

libstdc++-v3/testsuite/26_numerics/complex/50880.cc

+// { dg-options "-std=gnu++0x" }
+//
+// Copyright (C) 2011 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 <complex>
+#include <testsuite_hooks.h> 
+
+template<typename T>
+  void test01_do()
+  {
+    bool test __attribute__((unused)) = true;
+
+    const std::complex<T> ca(T(-2), T(2));
+    const std::complex<T> cb(T(-2), T(0));
+    const std::complex<T> cc(T(-2), T(-2));
+
+    std::complex<T> cra = std::acosh(ca);
+    std::complex<T> crb = std::acosh(cb);
+    std::complex<T> crc = std::acosh(cc);
+
+    VERIFY( cra.real() > T(0) );
+    VERIFY( crb.real() > T(0) );
+    VERIFY( crc.real() > T(0) );
+  }
+
+// libstdc++/50880
+void test01()
+{
+  test01_do<float>();
+  test01_do<double>();
+  test01_do<long double>();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}

libstdc++-v3/testsuite/tr1/8_c_compatibility/complex/50880.cc

+// Copyright (C) 2011 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 <tr1/complex>
+#include <testsuite_hooks.h> 
+
+template<typename T>
+  void test01_do()
+  {
+    bool test __attribute__((unused)) = true;
+
+    const std::complex<T> ca(T(-2), T(2));
+    const std::complex<T> cb(T(-2), T(0));
+    const std::complex<T> cc(T(-2), T(-2));
+
+    std::complex<T> cra = std::tr1::acosh(ca);
+    std::complex<T> crb = std::tr1::acosh(cb);
+    std::complex<T> crc = std::tr1::acosh(cc);
+
+    VERIFY( cra.real() > T(0) );
+    VERIFY( crb.real() > T(0) );
+    VERIFY( crc.real() > T(0) );
+  }
+
+// libstdc++/50880
+void test01()
+{
+  test01_do<float>();
+  test01_do<double>();
+  test01_do<long double>();
+}
+
+int main()
+{
+  test01();
+  return 0;
+}