7b4622514d
We recently noticed that the unwrap_iter.h file was pushing macros, but
it was pushing them again instead of popping them at the end of the
file. This led to libc++ basically swallowing any custom definition of
these macros in user code:
#define min HELLO
#include <algorithm>
// min is not HELLO anymore, it's not defined
While investigating this issue, I noticed that our push/pop pragmas were
actually entirely wrong too. Indeed, instead of pushing macros like
`move`, we'd push `move(int, int)` in the pragma, which is not a valid
macro name. As a result, we would not actually push macros like `move`
-- instead we'd simply undefine them. This led to the following code not
working:
#define move HELLO
#include <algorithm>
// move is not HELLO anymore
Fixing the pragma push/pop incantations led to a cascade of issues
because we use identifiers like `move` in a large number of places, and
all of these headers would now need to do the push/pop dance.
This patch fixes all these issues. First, it adds a check that we don't
swallow important names like min, max, move or refresh as explained
above. This is done by augmenting the existing
system_reserved_names.gen.py test to also check that the macros are what
we expect after including each header.
Second, it fixes the push/pop pragmas to work properly and adds missing
pragmas to all the files I could detect a failure in via the newly added
test.
rdar://121365472
82 lines
2.4 KiB
C++
82 lines
2.4 KiB
C++
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef _LIBCPP___ALGORITHM_RANGES_COPY_N_H
|
|
#define _LIBCPP___ALGORITHM_RANGES_COPY_N_H
|
|
|
|
#include <__algorithm/copy.h>
|
|
#include <__algorithm/in_out_result.h>
|
|
#include <__algorithm/iterator_operations.h>
|
|
#include <__algorithm/ranges_copy.h>
|
|
#include <__config>
|
|
#include <__functional/identity.h>
|
|
#include <__iterator/concepts.h>
|
|
#include <__iterator/incrementable_traits.h>
|
|
#include <__iterator/unreachable_sentinel.h>
|
|
#include <__iterator/wrap_iter.h>
|
|
#include <__utility/move.h>
|
|
|
|
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
|
|
# pragma GCC system_header
|
|
#endif
|
|
|
|
_LIBCPP_PUSH_MACROS
|
|
#include <__undef_macros>
|
|
|
|
_LIBCPP_BEGIN_NAMESPACE_STD
|
|
|
|
#if _LIBCPP_STD_VER >= 20
|
|
|
|
namespace ranges {
|
|
|
|
template <class _Ip, class _Op>
|
|
using copy_n_result = in_out_result<_Ip, _Op>;
|
|
|
|
namespace __copy_n {
|
|
struct __fn {
|
|
template <class _InIter, class _DiffType, class _OutIter>
|
|
_LIBCPP_HIDE_FROM_ABI constexpr static copy_n_result<_InIter, _OutIter>
|
|
__go(_InIter __first, _DiffType __n, _OutIter __result) {
|
|
while (__n != 0) {
|
|
*__result = *__first;
|
|
++__first;
|
|
++__result;
|
|
--__n;
|
|
}
|
|
return {std::move(__first), std::move(__result)};
|
|
}
|
|
|
|
template <random_access_iterator _InIter, class _DiffType, random_access_iterator _OutIter>
|
|
_LIBCPP_HIDE_FROM_ABI constexpr static copy_n_result<_InIter, _OutIter>
|
|
__go(_InIter __first, _DiffType __n, _OutIter __result) {
|
|
auto __ret = std::__copy<_RangeAlgPolicy>(__first, __first + __n, __result);
|
|
return {__ret.first, __ret.second};
|
|
}
|
|
|
|
template <input_iterator _Ip, weakly_incrementable _Op>
|
|
requires indirectly_copyable<_Ip, _Op>
|
|
_LIBCPP_HIDE_FROM_ABI constexpr copy_n_result<_Ip, _Op>
|
|
operator()(_Ip __first, iter_difference_t<_Ip> __n, _Op __result) const {
|
|
return __go(std::move(__first), __n, std::move(__result));
|
|
}
|
|
};
|
|
} // namespace __copy_n
|
|
|
|
inline namespace __cpo {
|
|
inline constexpr auto copy_n = __copy_n::__fn{};
|
|
} // namespace __cpo
|
|
} // namespace ranges
|
|
|
|
#endif // _LIBCPP_STD_VER >= 20
|
|
|
|
_LIBCPP_END_NAMESPACE_STD
|
|
|
|
_LIBCPP_POP_MACROS
|
|
|
|
#endif // _LIBCPP___ALGORITHM_RANGES_COPY_N_H
|