[PATCH PR libstdc++/88341] -

[Ed Smith-Rowland]

Committed as obvious 266788.

Ed



2018-12-03  Edward Smith-Rowland  <3dw...@verizon.net>

        PR libstdc++/88341 - Complex norm doesn't compile with C++11
        * include/std/complex (_S_do_it): Make C++20 constexpr.
        * testsuite/26_numerics/complex/value_operations/pr88341.cc: New test.


Index: include/std/complex
===================================================================
--- include/std/complex (revision 266769)
+++ include/std/complex (working copy)
@@ -659,7 +659,7 @@
     struct _Norm_helper
     {
       template<typename _Tp>
-        static inline _GLIBCXX_CONSTEXPR _Tp _S_do_it(const complex<_Tp>& __z)
+        static inline _GLIBCXX20_CONSTEXPR _Tp _S_do_it(const complex<_Tp>& 
__z)
         {
           const _Tp __x = __z.real();
           const _Tp __y = __z.imag();
@@ -671,7 +671,7 @@
     struct _Norm_helper<true>
     {
       template<typename _Tp>
-        static inline _GLIBCXX_CONSTEXPR _Tp _S_do_it(const complex<_Tp>& __z)
+        static inline _GLIBCXX20_CONSTEXPR _Tp _S_do_it(const complex<_Tp>& 
__z)
         {
           //_Tp __res = std::abs(__z);
           //return __res * __res;
Index: testsuite/26_numerics/complex/value_operations/pr88341.cc
===================================================================
--- testsuite/26_numerics/complex/value_operations/pr88341.cc   (nonexistent)
+++ testsuite/26_numerics/complex/value_operations/pr88341.cc   (working copy)
@@ -0,0 +1,27 @@
+// { dg-options "-std=gnu++11" }
+// { dg-do compile { target c++11 } }
+
+// Copyright (C) 2018 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>
+
+double
+n(std::complex<double>& c)
+{
+  return std::norm(c);
+}