libstdc++-v3/testsuite/ext/ext_pointer/1_neg.cc

   1 // Bob Walters 10-2008
   2
   3 // Test for Container using non-standard pointer types.
   4
   5 // Copyright (C) 2008-2013 Free Software Foundation, Inc.
   6 //
   7 // This file is part of the GNU ISO C++ Library.  This library is free
   8 // software; you can redistribute it and/or modify it under the
   9 // terms of the GNU General Public License as published by the
  10 // Free Software Foundation; either version 3, or (at your option)
  11 // any later version.
  12
  13 // This library is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License along
  19 // with this library; see the file COPYING3.  If not see
  20 // <http://www.gnu.org/licenses/>.
  21
  22
  23 // { dg-do compile }
  24
  25 #include <algorithm>
  26 #include <testsuite_hooks.h>
  27 #include <ext/pointer.h>
  28
  29 using __gnu_cxx::_Pointer_adapter;
  30 using __gnu_cxx::_Relative_pointer_impl;
  31 using __gnu_cxx::__static_pointer_cast;
  32 using __gnu_cxx::__const_pointer_cast;
  33
  34
  35 struct A {
  36   int i;
  37 };
  38 struct B : public A{
  39   int j;
  40 };
  41 typedef _Pointer_adapter<_Relative_pointer_impl<B> > B_pointer;
  42 typedef _Pointer_adapter<_Relative_pointer_impl<const B> > const_B_pointer;
  43 typedef _Pointer_adapter<_Relative_pointer_impl<A> > A_pointer;
  44 typedef _Pointer_adapter<_Relative_pointer_impl<const A> > const_A_pointer;
  45
  46
  47 void test01(void) {
  48   bool test __attribute__((unused)) = true;
  49
  50   A a;
  51   B b;
  52
  53   A_pointer aptr( &a );
  54
  55   // Can't implicitly cast from A* to B*
  56   B_pointer bptr1(aptr); // { dg-error "required from here" 31 }
  57   B_pointer bptr2(&a); // { dg-error "required from here" 32 }
  58
  59   // but explicit cast/conversion is OK.
  60   B_pointer bptr3(__static_pointer_cast<B_pointer>(aptr)); // ok
  61   B_pointer bptr4(__static_pointer_cast<B_pointer>(&a)); // ok
  62
  63   // Can't implicitly cast from A* to B*
  64   bptr1 = aptr; // { dg-error "required from here" 39 }
  65   bptr1 = &a; // { dg-error "required from here" 40 }
  66
  67   // but explicit cast/conversion is OK.
  68   bptr1 = __static_pointer_cast<B_pointer>(aptr); // ok
  69   bptr1 = __static_pointer_cast<B_pointer>(&a); // ok
  70
  71   // Similarly, can't shed constness via implicit cast
  72   const_A_pointer captr(&a);
  73   A_pointer aptr2(captr); // { dg-error "required from here" 48 }
  74
  75   // but explicit cast/conversion is OK.
  76   A_pointer aptr3(__const_pointer_cast<A_pointer>(captr)); // ok
  77
  78   // Similarly, can't shed constness via implicit cast
  79   aptr2 = captr; // { dg-error "required from here" 54 }
  80
  81   // but explicit cast/conversion is OK.
  82   aptr3 = __const_pointer_cast<A_pointer>(captr); // ok
  83
  84   // Combine explicit const cast with implicit downcast.
  85   const_B_pointer cbptr(&b);
  86   A_pointer aptr4(cbptr); // { dg-error "required from here" 61 }
  87   aptr4 = cbptr; // { dg-error "required from here" 62 }
  88
  89   A_pointer aptr5(__const_pointer_cast<B_pointer>(cbptr)); // ok
  90   aptr5 = __const_pointer_cast<B_pointer>(cbptr);  // ok
  91 }
  92
  93 // { dg-prune-output "include" }