From 256f67aa078de0e7bf53a0870c2cb87ab90cda09 Mon Sep 17 00:00:00 2001 From: Jonathan Wakely Date: Wed, 19 Feb 2020 21:45:59 +0000 Subject: [PATCH] libstdc++: Simplify std::three_way_comparable_with (LWG 3360) This also removes a useless condition that was supposed to be removed by the P1959R0 changes, but left in when that was implemented. * libsupc++/compare (three_way_comparable): Remove always-false check that should have been removed with weak_equality (P1959R0). (three_way_comparable_with): Likewise. Reorder requirements (LWG 3360). --- libstdc++-v3/ChangeLog | 4 ++++ libstdc++-v3/libsupc++/compare | 10 ++++------ 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog index 1711a359256..622c2948eab 100644 --- a/libstdc++-v3/ChangeLog +++ b/libstdc++-v3/ChangeLog @@ -1,5 +1,9 @@ 2020-02-19 Jonathan Wakely + * libsupc++/compare (three_way_comparable): Remove always-false check + that should have been removed with weak_equality (P1959R0). + (three_way_comparable_with): Likewise. Reorder requirements (LWG 3360). + * include/std/concepts (__detail::__partially_ordered_with): Move here from . (totally_ordered, totally_ordered_with): Use __partially_ordered_with diff --git a/libstdc++-v3/libsupc++/compare b/libstdc++-v3/libsupc++/compare index a74ebc845bf..b88b691b9e1 100644 --- a/libstdc++-v3/libsupc++/compare +++ b/libstdc++-v3/libsupc++/compare @@ -417,8 +417,7 @@ namespace std template concept three_way_comparable = __detail::__weakly_eq_cmp_with<_Tp, _Tp> - && (!convertible_to<_Cat, partial_ordering> - || __detail::__partially_ordered_with<_Tp, _Tp>) + && __detail::__partially_ordered_with<_Tp, _Tp> && requires(const remove_reference_t<_Tp>& __a, const remove_reference_t<_Tp>& __b) { { __a <=> __b } -> __detail::__compares_as<_Cat>; @@ -426,16 +425,15 @@ namespace std template concept three_way_comparable_with - = __detail::__weakly_eq_cmp_with<_Tp, _Up> - && (!convertible_to<_Cat, partial_ordering> - || __detail::__partially_ordered_with<_Tp, _Up>) - && three_way_comparable<_Tp, _Cat> + = three_way_comparable<_Tp, _Cat> && three_way_comparable<_Up, _Cat> && common_reference_with&, const remove_reference_t<_Up>&> && three_way_comparable< common_reference_t&, const remove_reference_t<_Up>&>, _Cat> + && __detail::__weakly_eq_cmp_with<_Tp, _Up> + && __detail::__partially_ordered_with<_Tp, _Up> && requires(const remove_reference_t<_Tp>& __t, const remove_reference_t<_Up>& __u) { { __t <=> __u } -> __detail::__compares_as<_Cat>; -- 2.30.2