Since std::move is nothing more than a cast, part of STL and not the
language itself, it's easy to provide a custom implementation if one
wishes not to include the entirety of <utility>.
Added flag (MoveFunction) provides a way to continue using this
essential check even with the custom implementation of moving.
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Co-authored-by: EugeneZelenko <eugene.zelenko@gmail.com>
Warn when an rvalue reference function paramter is never moved
from within the function body.
Reviewed By: carlosgalvezp
Differential Revision: https://reviews.llvm.org/D141569