Skip to content

Implement LWG-3919 enumerate_view may invoke UB for sized common non-forward underlying ranges #4526

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Mar 28, 2024
Merged

Implement LWG-3919 enumerate_view may invoke UB for sized common non-forward underlying ranges #4526

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions stl/inc/ranges
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6386,7 +6386,7 @@ namespace ranges {
_NODISCARD constexpr auto end() noexcept(_Is_end_nothrow_v<_Vw>) // strengthened
requires (!_Simple_view<_Vw>)
{
if constexpr (common_range<_Vw> && sized_range<_Vw>) {
if constexpr (forward_range<_Vw> && common_range<_Vw> && sized_range<_Vw>) {
return _Iterator<false>{_RANGES end(_Range), _RANGES distance(_Range)};
} else {
return _Sentinel<false>{_RANGES end(_Range)};
Expand All @@ -6396,7 +6396,7 @@ namespace ranges {
_NODISCARD constexpr auto end() const noexcept(_Is_end_nothrow_v<const _Vw>) // strengthened
requires _Range_with_movable_references<const _Vw>
{
if constexpr (common_range<const _Vw> && sized_range<const _Vw>) {
if constexpr (forward_range<const _Vw> && common_range<const _Vw> && sized_range<const _Vw>) {
return _Iterator<true>{_RANGES end(_Range), _RANGES distance(_Range)};
} else {
return _Sentinel<true>{_RANGES end(_Range)};
Expand Down
5 changes: 3 additions & 2 deletions tests/std/tests/P2164R9_views_enumerate/test.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -203,7 +203,7 @@ constexpr bool test_one(Rng&& rng, Expected&& expected) {
assert((as_const(r).begin() == s) == is_empty);
}

STATIC_ASSERT(common_range<R> == (common_range<V> && sized_range<V>) );
STATIC_ASSERT(common_range<R> == (forward_range<V> && common_range<V> && sized_range<V>) );
if constexpr (common_range<V> && sized_range<V> && bidirectional_range<V>) {
if (!is_empty) {
assert(*prev(s) == *prev(end(expected)));
Expand All @@ -228,7 +228,8 @@ constexpr bool test_one(Rng&& rng, Expected&& expected) {
assert((r.begin() == cs) == is_empty);
}

STATIC_ASSERT(common_range<const R> == (common_range<const V> && sized_range<const V>) );
STATIC_ASSERT(
common_range<const R> == (forward_range<const V> && common_range<const V> && sized_range<const V>) );
if constexpr (common_range<const V> && sized_range<const V> && bidirectional_range<const V>) {
if (!is_empty) {
assert(*prev(cs) == *prev(end(expected)));
Expand Down