Jonathan Wakely
93843da697
libstdc++: Add comparison operators to associative containers
The last C++20 changes from P1614R2, "The Mothership has Landed"
* include/bits/stl_map.h (map): Define operator<=> and remove
operator< for C++20.
* include/bits/stl_multimap.h (multimap): Likewise.
* include/bits/stl_multiset.h (multiset): Likewise.
* include/bits/stl_set.h (set): Likewise.
* include/bits/stl_tree.h (_Rb_tree): Likewise.
(_Rb_tree_iterator, _Rb_tree_const_iterator): Remove redundant
operator!= for C++20.
* include/debug/map.h (__gnu_debug::map): Define operator<=> for C++20.
* include/debug/multimap.h (__gnu_debug::multimap): Likewise.
* include/debug/multiset.h (__gnu_debug::multiset): Likewise.
* include/debug/set.h (__gnu_debug::set): Likewise.
* testsuite/23_containers/map/operators/cmp_c++20.cc: New test.
* testsuite/23_containers/multimap/operators/cmp_c++20.cc: New test.
* testsuite/23_containers/multiset/operators/cmp_c++20.cc: New test.
* testsuite/23_containers/set/operators/cmp_c++20.cc: New test.