When I remove <bits/stl_algobase.h> for importing __memcmp (my apologies for
writing __memcpy) from libstdc++-v3/include/bits/ranges_algobase.h and try to
rerun the code, I get the following error:
In file included from
$HOME/projects/objdirforgcc/_pfx/include/c++/15.0.0/numeric:69,
from ranges-iota-fix.cpp:1:
$HOME/projects/objdirforgcc/_pfx/include/c++/15.0.0/bits/ranges_algobase.h: In
member function ‘constexpr bool std::ranges::__equal_fn::operator()(_Iter1,
_Sent1, _Iter2, _Sent2, _Pred, _Proj1, _Proj2) const’:
$HOME/projects/objdirforgcc/_pfx/include/c++/15.0.0/bits/ranges_algobase.h:143:32:
error: ‘__memcmp’ is not a member of ‘std’; did you mean ‘__memcmpable’?
143 | return !std::__memcmp(__first1, __first2, __len);
| ^~~~~~~~
| __memcmpable
From: jwak...@redhat.com At: 05/24/24 10:12:57 UTC-4:00To: Michael Levine
(BLOOMBERG/ 731 LEX )
Cc: ppa...@redhat.com, gcc-patches@gcc.gnu.org, libstd...@gcc.gnu.org
Subject: Re: [PATCH v3] libstdc++: Fix std::ranges::iota not in numeric
[PR108760]
On 24/05/24 13:56 -0000, Michael Levine (BLOOMBERG/ 731 LEX) wrote:
>I've attached the v3 version of the patch as a single, squashed patch
containing all of the changes. I manually prepended my sign off to the patch.
>Signed-off-by: Michael Levine <mlevin...@bloomberg.net>
>---
>diff --git a/libstdc++-v3/include/bits/ranges_algo.h
b/libstdc++-v3/include/bits/ranges_algo.h
>index 62faff173bd..d258be0b93f 100644
>--- a/libstdc++-v3/include/bits/ranges_algo.h
>+++ b/libstdc++-v3/include/bits/ranges_algo.h
>@@ -3521,58 +3521,6 @@ namespace ranges
>
> #endif // __glibcxx_ranges_contains
>
>-#if __glibcxx_ranges_iota >= 202202L // C++ >= 23
>-
>- template<typename _Out, typename _Tp>
>- struct out_value_result
>- {
>- [[no_unique_address]] _Out out;
>- [[no_unique_address]] _Tp value;
>-
>- template<typename _Out2, typename _Tp2>
>- requires convertible_to<const _Out&, _Out2>
>- && convertible_to<const _Tp&, _Tp2>
>- constexpr
>- operator out_value_result<_Out2, _Tp2>() const &
>- { return {out, value}; }
>-
>- template<typename _Out2, typename _Tp2>
>- requires convertible_to<_Out, _Out2>
>- && convertible_to<_Tp, _Tp2>
>- constexpr
>- operator out_value_result<_Out2, _Tp2>() &&
>- { return {std::move(out), std::move(value)}; }
>- };
>-
>- template<typename _Out, typename _Tp>
>- using iota_result = out_value_result<_Out, _Tp>;
>-
>- struct __iota_fn
>- {
>- template<input_or_output_iterator _Out, sentinel_for<_Out> _Sent,
weakly_incrementable _Tp>
>- requires indirectly_writable<_Out, const _Tp&>
>- constexpr iota_result<_Out, _Tp>
>- operator()(_Out __first, _Sent __last, _Tp __value) const
>- {
>- while (__first != __last)
>- {
>- *__first = static_cast<const _Tp&>(__value);
>- ++__first;
>- ++__value;
>- }
>- return {std::move(__first), std::move(__value)};
>- }
>-
>- template<weakly_incrementable _Tp, output_range<const _Tp&> _Range>
>- constexpr iota_result<borrowed_iterator_t<_Range>, _Tp>
>- operator()(_Range&& __r, _Tp __value) const
>- { return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__value)); }
>- };
>-
>- inline constexpr __iota_fn iota{};
>-
>-#endif // __glibcxx_ranges_iota
>-
> #if __glibcxx_ranges_find_last >= 202207L // C++ >= 23
>
> struct __find_last_fn
>diff --git a/libstdc++-v3/include/bits/ranges_algobase.h
b/libstdc++-v3/include/bits/ranges_algobase.h
>index e26a73a27d6..965b36aed35 100644
>--- a/libstdc++-v3/include/bits/ranges_algobase.h
>+++ b/libstdc++-v3/include/bits/ranges_algobase.h
>@@ -35,6 +35,7 @@
> #include <compare>
> #include <bits/stl_iterator_base_funcs.h>
> #include <bits/stl_iterator.h>
>+#include <bits/stl_algobase.h> // __memcpy
Why is this being added here? What is __memcpy?
I don't think out_value_result requires any new headers to be included
here, does it?
> #include <bits/ranges_base.h> // ranges::begin, ranges::range etc.
> #include <bits/invoke.h> // __invoke
> #include <bits/cpp_type_traits.h> // __is_byte
>@@ -70,6 +71,32 @@ namespace ranges
> __is_move_iterator<move_iterator<_Iterator>> = true;
> } // namespace __detail
>
>+#if __glibcxx_ranges_iota >= 202202L // C++ >= 23
>+
>+ template<typename _Out, typename _Tp>
>+ struct out_value_result
>+ {
>+ [[no_unique_address]] _Out out;
>+ [[no_unique_address]] _Tp value;
>+
>+ template<typename _Out2, typename _Tp2>
>+ requires convertible_to<const _Out&, _Out2>
>+ && convertible_to<const _Tp&, _Tp2>
>+ constexpr
>+ operator out_value_result<_Out2, _Tp2>() const &
>+ { return {out, value}; }
>+
>+ template<typename _Out2, typename _Tp2>
>+ requires convertible_to<_Out, _Out2>
>+ && convertible_to<_Tp, _Tp2>
>+ constexpr
>+ operator out_value_result<_Out2, _Tp2>() &&
>+ { return {std::move(out), std::move(value)}; }
>+ };
>+
>+#endif // __glibcxx_ranges_iota
>+
>+
> struct __equal_fn
> {
> template<input_iterator _Iter1, sentinel_for<_Iter1> _Sent1,
>diff --git a/libstdc++-v3/include/std/numeric
b/libstdc++-v3/include/std/numeric
>index c912db4a519..d88f7f02137 100644
>--- a/libstdc++-v3/include/std/numeric
>+++ b/libstdc++-v3/include/std/numeric
>@@ -65,6 +65,10 @@
> # include <parallel/numeric>
> #endif
>
>+#if __glibcxx_ranges_iota >= 202202L // C++ >= 23
>+#include <bits/ranges_algobase.h> // for out_value_result as used by
std::ranges::iota. It transitively also brings in <bits/ranges_base.h>, from
which _Range is used by std::ranges::iota
We generally try to keep lines below 80 columns, or 120 at a push.
This is unnecessarily long, and I don't know what _Range is meant to
be (that's just a template parameter, not something defined in
<bits/ranges_algobase.h>. Please just use:
#include <bits/ranges_algobase.h> // for ranges::out_value_result
Otherwise this looks ready to go in, thanks.
>+#endif // __glibcxx_ranges_iota
>+
> #if __cplusplus >= 201402L
> # include <type_traits>
> # include <bit>
>@@ -726,6 +730,40 @@ namespace __detail
> /// @} group numeric_ops
> #endif // C++17
>
>+namespace ranges
>+{
>+#if __glibcxx_ranges_iota >= 202202L // C++ >= 23
>+
>+ template<typename _Out, typename _Tp>
>+ using iota_result = out_value_result<_Out, _Tp>;
>+
>+ struct __iota_fn
>+ {
>+ template<input_or_output_iterator _Out, sentinel_for<_Out> _Sent,
weakly_incrementable _Tp>
>+ requires indirectly_writable<_Out, const _Tp&>
>+ constexpr iota_result<_Out, _Tp>
>+ operator()(_Out __first, _Sent __last, _Tp __value) const
>+ {
>+ while (__first != __last)
>+ {
>+ *__first = static_cast<const _Tp&>(__value);
>+ ++__first;
>+ ++__value;
>+ }
>+ return {std::move(__first), std::move(__value)};
>+ }
>+
>+ template<weakly_incrementable _Tp, output_range<const _Tp&> _Range>
>+ constexpr iota_result<borrowed_iterator_t<_Range>, _Tp>
>+ operator()(_Range&& __r, _Tp __value) const
>+ { return (*this)(ranges::begin(__r), ranges::end(__r),
std::move(__value)); }
>+ };
>+
>+ inline constexpr __iota_fn iota{};
>+
>+#endif // __glibcxx_ranges_iota
>+} // namespace ranges
>+
> _GLIBCXX_END_NAMESPACE_VERSION
> } // namespace std
>
>diff --git a/libstdc++-v3/testsuite/25_algorithms/iota/1.cc
b/libstdc++-v3/testsuite/26_numerics/iota/2.cc
>similarity index 96%
>rename from libstdc++-v3/testsuite/25_algorithms/iota/1.cc
>rename to libstdc++-v3/testsuite/26_numerics/iota/2.cc
>index 61bf418b4da..040c48d91ce 100644
>--- a/libstdc++-v3/testsuite/25_algorithms/iota/1.cc
>+++ b/libstdc++-v3/testsuite/26_numerics/iota/2.cc
>@@ -1,6 +1,6 @@
> // { dg-do run { target c++23 } }
>
>-#include <algorithm>
>+#include <numeric>
> #include <testsuite_hooks.h>
> #include <testsuite_iterators.h>
>
