OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Fix std::hash<std::error_condition>

Browse Source 
The hash value should be based on the identity (i.e. address) of the
error_category member, not its object representation (i.e. underlying
bytes).

	* include/std/system_error (error_code): Remove friend declaration
	for hash<error_code>.
	(hash<error_code>::operator()): Use public member functions to access
	value and category.
	(hash<error_condition>::operator()): Use address of category, not
	its object representation.
	* src/c++11/compatibility-c++0x.cc (hash<error_code>::operator()):
	Use public member functions to access value and category.
	* testsuite/19_diagnostics/error_condition/hash.cc: New test.

From-SVN: r270872
This commit is contained in:
Jonathan Wakely 2019-05-04 15:35:25 +01:00 committed by Jonathan Wakely
parent 34d9c2c269
commit fe6fb0d159
4 changed files with 69 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
libstdc++-v3/ChangeLog
View File

@ -1,3 +1,15 @@
2019-05-04 Jonathan Wakely <jwakely@redhat.com>
* include/std/system_error (error_code): Remove friend declaration
for hash<error_code>.
(hash<error_code>::operator()): Use public member functions to access
value and category.
(hash<error_condition>::operator()): Use address of category, not
its object representation.
* src/c++11/compatibility-c++0x.cc (hash<error_code>::operator()):
Use public member functions to access value and category.
* testsuite/19_diagnostics/error_condition/hash.cc: New test.
2019-05-04 François Dumont <fdumont@gcc.gnu.org>
PR libstdc++/90277

10
libstdc++-v3/include/std/system_error
View File

@ -193,8 +193,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
// DR 804.
private:
friend class hash<error_code>;
int _M_value;
const error_category* _M_cat;
};
@ -394,13 +392,13 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
size_t
operator()(const error_code& __e) const noexcept
{
const size_t __tmp = std::_Hash_impl::hash(__e._M_value);
return std::_Hash_impl::__hash_combine(__e._M_cat, __tmp);
const size_t __tmp = std::_Hash_impl::hash(__e.value());
return std::_Hash_impl::__hash_combine(&__e.category(), __tmp);
}
};
#endif // _GLIBCXX_COMPATIBILITY_CXX0X
#if __cplusplus > 201402L
#if __cplusplus >= 201703L
// DR 2686.
/// std::hash specialization for error_condition.
template<>
@ -411,7 +409,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
operator()(const error_condition& __e) const noexcept
{
const size_t __tmp = std::_Hash_impl::hash(__e.value());
return std::_Hash_impl::__hash_combine(__e.category(), __tmp);
return std::_Hash_impl::__hash_combine(&__e.category(), __tmp);
}
};
#endif

4
libstdc++-v3/src/c++11/compatibility-c++0x.cc
View File

@ -117,8 +117,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
size_t
hash<error_code>::operator()(error_code __e) const
{
const size_t __tmp = std::_Hash_impl::hash(__e._M_value);
return std::_Hash_impl::__hash_combine(__e._M_cat, __tmp);
const size_t __tmp = std::_Hash_impl::hash(__e.value());
return std::_Hash_impl::__hash_combine(&__e.category(), __tmp);
}
// gcc-4.7.0

51
libstdc++-v3/testsuite/19_diagnostics/error_condition/hash.cc Normal file
View File

@ -0,0 +1,51 @@
// Copyright (C) 2019 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING3. If not see
// <http://www.gnu.org/licenses/>.
// { dg-options "-std=gnu++17" }
// { dg-do run { target c++17 } }
#include <system_error>
#include <testsuite_hooks.h>
struct error_cat : std::error_category
{
error_cat(std::string s) : _name(s) { }
std::string _name;
const char* name() const noexcept override { return _name.c_str(); }
std::string message(int) const override { return "error"; }
};
void
test01()
{
std::hash<std::error_condition> h;
error_cat kitty("kitty"), moggy("moggy");
std::error_condition cond1(99, kitty);
VERIFY( h(cond1) == h(cond1) );
std::error_condition cond2(99, kitty);
VERIFY( h(cond1) == h(cond2) );
std::error_condition cond3(88, kitty);
VERIFY( h(cond1) != h(cond3) );
std::error_condition cond4(99, moggy);
VERIFY( h(cond1) != h(cond4) );
}
int
main()
{
test01();
}