1// Copyright (C) 1994-2020 Free Software Foundation, Inc.
2//
3// This file is part of GCC.
4//
5// GCC is free software; you can redistribute it and/or modify
6// it under the terms of the GNU General Public License as published by
7// the Free Software Foundation; either version 3, or (at your option)
8// any later version.
9
10// GCC is distributed in the hope that it will be useful,
11// but WITHOUT ANY WARRANTY; without even the implied warranty of
12// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13// GNU General Public License for more details.
14
15// Under Section 7 of GPL version 3, you are granted additional
16// permissions described in the GCC Runtime Library Exception, version
17// 3.1, as published by the Free Software Foundation.
18
19// You should have received a copy of the GNU General Public License and
20// a copy of the GCC Runtime Library Exception along with this program;
21// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
22// <http://www.gnu.org/licenses/>.
23
24#include "tinfo.h"
25
26namespace __cxxabiv1 {
27
28__pbase_type_info::
29~__pbase_type_info ()
30{}
31
32bool __pbase_type_info::
33__do_catch (const type_info *thr_type,
34            void **thr_obj,
35            unsigned outer) const
36{
37  if (*this == *thr_type)
38    return true;      // same type
39
40#if __cpp_rtti
41  if (*thr_type == typeid (nullptr))
42    {
43      // A catch handler for any pointer type matches nullptr_t.
44      if (typeid (*this) == typeid(__pointer_type_info))
45        {
46          *thr_obj = nullptr;
47          return true;
48        }
49      else if (typeid (*this) == typeid(__pointer_to_member_type_info))
50        {
51          if (__pointee->__is_function_p ())
52            {
53              using pmf_type = void (__pbase_type_info::*)();
54              static const pmf_type pmf = nullptr;
55              *thr_obj = const_cast<pmf_type*>(&pmf);
56              return true;
57            }
58          else
59            {
60              using pm_type = int __pbase_type_info::*;
61              static const pm_type pm = nullptr;
62              *thr_obj = const_cast<pm_type*>(&pm);
63              return true;
64            }
65        }
66    }
67
68  if (typeid (*this) != typeid (*thr_type))
69    return false;     // not both same kind of pointers
70#endif
71
72  if (!(outer & 1))
73    // We're not the same and our outer pointers are not all const qualified
74    // Therefore there must at least be a qualification conversion involved
75    // But for that to be valid, our outer pointers must be const qualified.
76    return false;
77
78  const __pbase_type_info *thrown_type =
79    static_cast <const __pbase_type_info *> (thr_type);
80
81  unsigned tflags = thrown_type->__flags;
82
83  const unsigned fqual_mask = __transaction_safe_mask|__noexcept_mask;
84  unsigned throw_fqual = (tflags & fqual_mask);
85  unsigned catch_fqual = (__flags & fqual_mask);
86  if (throw_fqual & ~catch_fqual)
87    /* Catch can perform a function pointer conversion.  */
88    tflags &= catch_fqual;
89  if (catch_fqual & ~throw_fqual)
90    /* But not the reverse.  */
91    return false;
92
93  if (tflags & ~__flags)
94    // We're less qualified.
95    return false;
96
97  if (!(__flags & __const_mask))
98    outer &= ~1;
99
100  return __pointer_catch (thrown_type, thr_obj, outer);
101}
102
103}
104