libstdc++-v3/testsuite/experimental/propagate_const/observers/1.cc

   1 // { dg-do run { target c++14 } }
   2 // { dg-options "-fdelete-null-pointer-checks" }
   3
   4 // Copyright (C) 2015-2021 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <experimental/propagate_const>
  22 #include <testsuite_hooks.h>
  23
  24 using std::experimental::propagate_const;
  25 using std::hash;
  26
  27 int main()
  28 {
  29   int x{42};
  30   propagate_const<int*> xx{&x};
  31   VERIFY(bool(xx));
  32   propagate_const<int*> xx2{};
  33   VERIFY(!bool(xx2));
  34   struct X {int x;};
  35   X x3{42};
  36   propagate_const<X*> xx3{&x3};
  37   VERIFY(xx3->x == 42);
  38   VERIFY((*xx3).x == 42);
  39   VERIFY(xx3.get() == &x3);
  40   const propagate_const<X*> xx4{&x3};
  41   VERIFY(xx4->x == 42);
  42   VERIFY((*xx4).x == 42);
  43   VERIFY(xx4.get() == &x3);
  44   static constexpr int x4{42};
  45   constexpr propagate_const<const int*> xx5{&x4};
  46   static_assert(bool(xx5), "");
  47   constexpr propagate_const<const int*> xx6{};
  48   static_assert(!bool(xx6), "");
  49   struct X2 {int x;};
  50   static constexpr X2 x5{42};
  51   constexpr propagate_const<const X2*> xx7{&x5};
  52   static_assert(xx7->x == 42, "");
  53   static_assert((*xx7).x == 42, "");
  54   static_assert(xx7.get() == &x5, "");
  55   struct X3
  56   {
  57     int f() {return 42;}
  58     int f() const {return 666;}
  59   };
  60   X3 xx8;
  61   propagate_const<X3*> xx9{&xx8};
  62   const propagate_const<X3*> xx10{&xx8};
  63   VERIFY(xx9->f() == 42);
  64   VERIFY(xx10->f() == 666);
  65 }