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| author | Jonathan Wakely <jwakely@redhat.com> | 2025-05-01 22:56:56 +0100 |
|---|---|---|
| committer | Jonathan Wakely <redi@gcc.gnu.org> | 2025-05-06 13:00:44 +0100 |
| commit | ac9fec014df8d75c2185981c9d191d1080e98094 (patch) | |
| tree | 743fad196207464def73e1232cba6698d3e7420a | |
| parent | 76c33109074b8e7cf6c326116b46792070122c7b (diff) | |
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libstdc++: Add noexcept to some std::counted_iterator operations
This was inspired by LWG 4245 but goes further. Anything which only
reads or writes the _M_length member can be noexcept. That
member is an iterator difference_type which means it's a signed integer
type or the __max_diff_type integer-like class type, so all arithmetic
and comparisons are non-throwing.
libstdc++-v3/ChangeLog:
* include/bits/stl_iterator.h (counted_iterator): Add noexcept
to friend operators which only access the _M_length member.
Reviewed-by: Tomasz Kamiński <tkaminsk@redhat.com>
| -rw-r--r-- | libstdc++-v3/include/bits/stl_iterator.h | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/libstdc++-v3/include/bits/stl_iterator.h b/libstdc++-v3/include/bits/stl_iterator.h index bed7295..478a98f 100644 --- a/libstdc++-v3/include/bits/stl_iterator.h +++ b/libstdc++-v3/include/bits/stl_iterator.h @@ -2511,17 +2511,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION [[nodiscard]] friend constexpr iter_difference_t<_It2> operator-(const counted_iterator& __x, - const counted_iterator<_It2>& __y) + const counted_iterator<_It2>& __y) noexcept { return __y._M_length - __x._M_length; } [[nodiscard]] friend constexpr iter_difference_t<_It> - operator-(const counted_iterator& __x, default_sentinel_t) + operator-(const counted_iterator& __x, default_sentinel_t) noexcept { return -__x._M_length; } [[nodiscard]] friend constexpr iter_difference_t<_It> - operator-(default_sentinel_t, const counted_iterator& __y) + operator-(default_sentinel_t, const counted_iterator& __y) noexcept { return __y._M_length; } constexpr counted_iterator& @@ -2548,19 +2548,19 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION [[nodiscard]] friend constexpr bool operator==(const counted_iterator& __x, - const counted_iterator<_It2>& __y) + const counted_iterator<_It2>& __y) noexcept { return __x._M_length == __y._M_length; } [[nodiscard]] friend constexpr bool - operator==(const counted_iterator& __x, default_sentinel_t) + operator==(const counted_iterator& __x, default_sentinel_t) noexcept { return __x._M_length == 0; } template<common_with<_It> _It2> [[nodiscard]] friend constexpr strong_ordering operator<=>(const counted_iterator& __x, - const counted_iterator<_It2>& __y) + const counted_iterator<_It2>& __y) noexcept { return __y._M_length <=> __x._M_length; } [[nodiscard]] |