https://gcc.gnu.org/g:4d1b19695669e6c67b9c3df07673bc22cae3a662
commit r15-8879-g4d1b19695669e6c67b9c3df07673bc22cae3a662
Author: Tomasz Kamiński <tkami...@redhat.com>
Date: Mon Mar 24 18:04:28 2025 +0100
libstdc++: Fix handling of common cpp20-only ranges for flat sets [PR119415]
These patch add check to verify if common range iterators satisfies
Cpp17LegacyIterator requirements (__detail::__cpp17_input_iterator),
before invoking overloads of insert that accepts two iterators.
As such overloads existed before c++20 iterators were introduced,
they commonly assume existence of iterator_traits<..>::iterator_category,
and passing a cpp20-only iterators, leads to hard errors.
In case if user-defined container wants to support more efficient
insertion in such cases, it should provided insert_range method,
as in the case of standard containers.
PR libstdc++/119415
libstdc++-v3/ChangeLog:
* include/std/flat_set (_Flat_set_impl:insert_range):
Add __detail::__cpp17_input_iterator check.
* testsuite/23_containers/flat_multiset/1.cc: New tests
* testsuite/23_containers/flat_set/1.cc: New tests
Reviewed-by: Patrick Palka <ppa...@redhat.com>, Jonathan Wakely
<jwak...@redhat.com>
Signed-off-by: Tomasz Kamiński <tkami...@redhat.com>
Diff:
---
libstdc++-v3/include/std/flat_set | 3 ++-
.../testsuite/23_containers/flat_multiset/1.cc | 27 ++++++++++++++++++++++
libstdc++-v3/testsuite/23_containers/flat_set/1.cc | 27 ++++++++++++++++++++++
3 files changed, 56 insertions(+), 1 deletion(-)
diff --git a/libstdc++-v3/include/std/flat_set
b/libstdc++-v3/include/std/flat_set
index 9240f2b9a2eb..bab56742ddd6 100644
--- a/libstdc++-v3/include/std/flat_set
+++ b/libstdc++-v3/include/std/flat_set
@@ -480,7 +480,8 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
typename container_type::iterator __it;
if constexpr (requires { _M_cont.insert_range(_M_cont.end(), __rg); })
__it = _M_cont.insert_range(_M_cont.end(), __rg);
- else if constexpr (ranges::common_range<_Rg>)
+ else if constexpr (ranges::common_range<_Rg>
+ &&
__detail::__cpp17_input_iterator<ranges::iterator_t<_Rg>>)
__it = _M_cont.insert(_M_cont.end(), ranges::begin(__rg),
ranges::end(__rg));
else
{
diff --git a/libstdc++-v3/testsuite/23_containers/flat_multiset/1.cc
b/libstdc++-v3/testsuite/23_containers/flat_multiset/1.cc
index 910f5dca5be4..cc31164315ae 100644
--- a/libstdc++-v3/testsuite/23_containers/flat_multiset/1.cc
+++ b/libstdc++-v3/testsuite/23_containers/flat_multiset/1.cc
@@ -143,6 +143,32 @@ test06()
VERIFY( std::ranges::equal(s, (int[]){1, 2, 3, 4, 5}) );
}
+template<typename T>
+struct NoInsertRange : std::vector<T>
+{
+ using std::vector<T>::vector;
+
+ template<typename It, typename R>
+ void insert_range(typename std::vector<T>::const_iterator, R&&) = delete;
+};
+
+void test07()
+{
+#ifdef __SIZEOF_INT128__
+ // PR libstdc++/119415 - flat_foo::insert_range cannot handle common ranges
+ // on c++20 only iterators
+ auto r = std::views::iota(__int128(1), __int128(6));
+
+ std::flat_multiset<int> s;
+ s.insert_range(r);
+ VERIFY( std::ranges::equal(s, (int[]){1, 2, 3, 4, 5}) );
+
+ std::flat_multiset<int, std::less<int>, NoInsertRange<int>> s2;
+ s2.insert_range(r);
+ VERIFY( std::ranges::equal(s2, (int[]){1, 2, 3, 4, 5}) );
+#endif
+}
+
int
main()
{
@@ -153,4 +179,5 @@ main()
test04();
test05();
test06();
+ test07();
}
diff --git a/libstdc++-v3/testsuite/23_containers/flat_set/1.cc
b/libstdc++-v3/testsuite/23_containers/flat_set/1.cc
index f0eaac936bf6..16881d788fcd 100644
--- a/libstdc++-v3/testsuite/23_containers/flat_set/1.cc
+++ b/libstdc++-v3/testsuite/23_containers/flat_set/1.cc
@@ -158,6 +158,32 @@ test06()
VERIFY( std::ranges::equal(s, (int[]){1, 2, 3, 4, 5}) );
}
+template<typename T>
+struct NoInsertRange : std::vector<T>
+{
+ using std::vector<T>::vector;
+
+ template<typename It, typename R>
+ void insert_range(typename std::vector<T>::const_iterator, R&&) = delete;
+};
+
+void test07()
+{
+#ifdef __SIZEOF_INT128__
+ // PR libstdc++/119415 - flat_foo::insert_range cannot handle common ranges
+ // on c++20 only iterators
+ auto r = std::views::iota(__int128(1), __int128(6));
+
+ std::flat_set<int> s;
+ s.insert_range(r);
+ VERIFY( std::ranges::equal(s, (int[]){1, 2, 3, 4, 5}) );
+
+ std::flat_set<int, std::less<int>, NoInsertRange<int>> s2;
+ s2.insert_range(r);
+ VERIFY( std::ranges::equal(s2, (int[]){1, 2, 3, 4, 5}) );
+#endif
+}
+
int
main()
{
@@ -168,4 +194,5 @@ main()
test04();
test05();
test06();
+ test07();
}
