On 03/03/20 11:30 -0500, Patrick Palka wrote:
We are passing a value type as the first argument to is_nothrow_assignable_v, but the result of that is always false. Since this predicate is a part of the condition that guards the corresponding optimizations for these algorithms, this bug means these optimizations are never used. We should be passing a reference type to is_nothrow_assignable_v instead.libstdc++-v3/ChangeLog: * include/bits/ranges_uninitialized.h (uninitialized_copy_fn::operator()): Pass a reference type as the first argument to is_nothrow_assignable_v. (uninitialized_copy_fn::operator()): Likewise. (uninitialized_move_fn::operator()): Likewise. Return an in_out_result with the input iterator stripped of its move_iterator. (uninitialized_move_n_fn::operator()): Likewise. (uninitialized_fill_fn::operator()): Pass a reference type as the first argument to is_nothrow_assignable_v. (uninitialized_fill_n_fn::operator()): Likewise.
OK.
