Fix C++98 std::signbit<long double>

	PR libstdc++/60637
	* include/c_global/cmath (signbit) [__cplusplus < 201103L]: Use
	__builtin_signbitf or __builtin_signbitl as appropriate.
	* testsuite/26_numerics/headers/cmath/60637.cc: New.

From-SVN: r232531

diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index d4af3e18248db3f116bc752ba1d1150badbeb1f9..7f48f89ddd6b124c8395539b02253756ab941c4a 100644 (file)
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,10 @@
+2016-01-18  Jonathan Wakely  <jwakely@redhat.com>
+
+       PR libstdc++/60637
+       * include/c_global/cmath (signbit) [__cplusplus < 201103L]: Use
+       __builtin_signbitf or __builtin_signbitl as appropriate.
+       * testsuite/26_numerics/headers/cmath/60637.cc: New.
+
 2016-01-12  Jonathan Wakely  <jwakely@redhat.com>
 
        PR libstdc++/69092

diff --git a/libstdc++-v3/include/c_global/cmath b/libstdc++-v3/include/c_global/cmath
index c53491244b783b6c82c8f762e570cb6398fd33d2..aae1517c0b21cae6366fa116237250b08339fd9d 100644 (file)
--- a/libstdc++-v3/include/c_global/cmath
+++ b/libstdc++-v3/include/c_global/cmath
@@ -855,7 +855,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
     signbit(_Tp __f)
     {
       typedef typename __gnu_cxx::__promote<_Tp>::__type __type;
-      return __builtin_signbit(__type(__f));
+      return sizeof(__type) == sizeof(float)
+       ? __builtin_signbitf(__type(__f))
+       : sizeof(__type) == sizeof(double)
+       ? __builtin_signbit(__type(__f))
+       : __builtin_signbitl(__type(__f));
     }
 
   template<typename _Tp>

diff --git a/libstdc++-v3/testsuite/26_numerics/headers/cmath/60637.cc b/libstdc++-v3/testsuite/26_numerics/headers/cmath/60637.cc
new file mode 100644 (file)
index 0000000..16a7896
--- /dev/null
+++ b/libstdc++-v3/testsuite/26_numerics/headers/cmath/60637.cc
@@ -0,0 +1,35 @@
+// Copyright (C) 2016 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++98 -ffast-math" }
+// { dg-do run { target i?86-*-* x86_64-*-* } }
+
+#include <cmath>
+#include <testsuite_hooks.h>
+
+void
+test01()
+{
+  long double ld = -5.3165867831218916301793863361917824e-2467L;
+  VERIFY( std::signbit(ld) == 1 );
+}
+
+int
+main()
+{
+  test01();
+}