re PR libstdc++/54112 (including complex.h and complex fails in C++03)

2012-08-13  Marc Glisse  <marc.glisse@inria.fr>

	PR libstdc++/54112
	* include/c_compatibility/complex.h: Undefine complex, always
	include system's complex.h if present.
	* testsuite/26_numerics/complex/c99.cc: New testcase.
	* testsuite/17_intro/headers/c++1998/complex.cc: Likewise.
	* doc/xml/manual/numerics.xml: Document it.

From-SVN: r190340

libstdc++-v3/ChangeLog

@@ -1,3 +1,12 @@
+2012-08-13  Marc Glisse  <marc.glisse@inria.fr>
+
+	PR libstdc++/54112
+	* include/c_compatibility/complex.h: Undefine complex, always
+	include system's complex.h if present.
+	* testsuite/26_numerics/complex/c99.cc: New testcase.
+	* testsuite/17_intro/headers/c++1998/complex.cc: Likewise.
+	* doc/xml/manual/numerics.xml: Document it.
+
 2012-08-12  Jonathan Wakely  <jwakely.gcc@gmail.com>
 
 	PR libstdc++/52681

libstdc++-v3/doc/xml/manual/numerics.xml

@@ -44,6 +44,11 @@
       prints <code>(u,v)</code> and <code>op&gt;&gt;</code> can read <code>u</code>,
       <code>(u)</code>, and <code>(u,v)</code>.
    </para>
+   <para>As an extension to C++11 and for increased compatibility with C,
+      <code>&lt;complex.h&gt;</code> includes both <code>&lt;complex&gt;</code>
+      and the C99 <code>&lt;complex.h&gt;</code> (if the C library provides
+      it).
+   </para>
 
   </section>
 </section>

libstdc++-v3/include/c_compatibility/complex.h

@@ -30,10 +30,11 @@
 
 #ifdef __GXX_EXPERIMENTAL_CXX0X__
 # include <ccomplex>
-#else
+#endif
-# if _GLIBCXX_HAVE_COMPLEX_H
+
-#  include_next <complex.h>
+#if _GLIBCXX_HAVE_COMPLEX_H
-# endif
+# include_next <complex.h>
+# undef complex
 #endif
 
 #ifndef _GLIBCXX_COMPLEX_H

libstdc++-v3/testsuite/17_intro/headers/c++1998/complex.cc

@@ -0,0 +1,26 @@
+// { dg-do compile }
+
+// 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/>.
+
+// libstdc++/54112
+#include <bits/c++config.h>
+#if _GLIBCXX_HAVE_COMPLEX_H
+# include <complex.h>
+#endif
+#include <tr1/complex>
+std::complex<double> x;

libstdc++-v3/testsuite/26_numerics/complex/c99.cc

@@ -0,0 +1,36 @@
+// { dg-do compile }
+// { dg-options "-std=gnu++11" }
+
+// 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/>.
+
+// libstdc++/54112
+#include <bits/c++config.h>
+#if _GLIBCXX_HAVE_COMPLEX_H
+# include <complex.h>
+#endif
+
+int main()
+{
+  bool test __attribute__((unused)) = true;
+
+#if _GLIBCXX_HAVE_COMPLEX_H
+  double _Complex x = .5;
+  double _Complex y = cacos (x);
+  (void)y;
+#endif
+}