libstdc++-v3/testsuite/24_iterators/istreambuf_iterator/92285.cc

   1 // Copyright (C) 2020-2024 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-require-effective-target hosted }
  19
  20 #include <iterator>
  21 #include <iostream>
  22 #include <testsuite_hooks.h>
  23
  24 // PR libstdc++/92285
  25 // See https://gcc.gnu.org/ml/libstdc++/2019-10/msg00129.html
  26
  27 typedef std::input_iterator_tag category;
  28 typedef std::char_traits<char>::off_type off_type;
  29 typedef std::iterator<category, char, off_type, char*, char> good; // { dg-warning "is deprecated" "" { target c++17 } }
  30 typedef std::iterator<category, char, off_type, char*, char&> bad; // { dg-warning "is deprecated" "" { target c++17 } }
  31
  32 bool check(good&) { return true; }
  33 void check(bad&) { }
  34
  35 void
  36 test01()
  37 {
  38   typedef std::istreambuf_iterator<char> I;
  39   I it;
  40   VERIFY( check(it) );
  41 #if __cplusplus < 201103L
  42   char c = 'c';
  43   I::reference r = c;
  44   VERIFY( &r == &c );
  45 #else
  46   static_assert( std::is_same<I::reference, char>::value, "LWG 445" );
  47 #endif
  48 }
  49
  50 int main()
  51 {
  52   test01();
  53 }