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      1 // Methods for type_info for -*- C++ -*- Run Time Type Identification.
      2 // Copyright (C) 1994-2024 Free Software Foundation, Inc.
      3 //
      4 // This file is part of GCC.
      5 //
      6 // GCC is free software; you can redistribute it and/or modify
      7 // it under the terms of the GNU General Public License as published by
      8 // the Free Software Foundation; either version 3, or (at your option)
      9 // any later version.
     10 
     11 // GCC is distributed in the hope that it will be useful,
     12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
     13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     14 // GNU General Public License for more details.
     15 
     16 // Under Section 7 of GPL version 3, you are granted additional
     17 // permissions described in the GCC Runtime Library Exception, version
     18 // 3.1, as published by the Free Software Foundation.
     19 
     20 // You should have received a copy of the GNU General Public License and
     21 // a copy of the GCC Runtime Library Exception along with this program;
     22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
     23 // <http://www.gnu.org/licenses/>.
     24 
     25 #include <bits/c++config.h>
     26 #include <cstddef>
     27 #include "tinfo.h"
     28 
     29 std::type_info::
     30 ~type_info ()
     31 { }
     32 
     33 #if !__GXX_TYPEINFO_EQUALITY_INLINE
     34 
     35 #if __cplusplus > 202002L
     36 # error "this file must be compiled with C++20 or older to define operator=="
     37 #endif
     38 
     39 // We can't rely on common symbols being shared between shared objects.
     40 bool std::type_info::
     41 operator== (const std::type_info& arg) const _GLIBCXX_NOEXCEPT
     42 {
     43 #if __GXX_MERGED_TYPEINFO_NAMES
     44   return name () == arg.name ();
     45 #else
     46   /* The name() method will strip any leading '*' prefix. Therefore
     47      take care to look at __name rather than name() when looking for
     48      the "pointer" prefix.  */
     49   return (&arg == this)
     50     || (__name[0] != '*' && (__builtin_strcmp (name (), arg.name ()) == 0));
     51 #endif
     52 }
     53 
     54 bool
     55 std::type_info::__equal (const std::type_info& arg) const _GLIBCXX_NOEXCEPT
     56 __attribute__((alias("_ZNKSt9type_infoeqERKS_")));
     57 #endif
     58 
     59 namespace std {
     60 
     61 // return true if this is a type_info for a pointer type
     62 bool type_info::
     63 __is_pointer_p () const
     64 {
     65   return false;
     66 }
     67 
     68 // return true if this is a type_info for a function type
     69 bool type_info::
     70 __is_function_p () const
     71 {
     72   return false;
     73 }
     74 
     75 // try and catch a thrown object.
     76 bool type_info::
     77 __do_catch (const type_info *thr_type, void **, unsigned) const
     78 {
     79   return *this == *thr_type;
     80 }
     81 
     82 // upcast from this type to the target. __class_type_info will override
     83 bool type_info::
     84 __do_upcast (const abi::__class_type_info *, void **) const
     85 {
     86   return false;
     87 }
     88 
     89 }
     90