Trivial relocation, std::swap, and a $2000 prize

This is the first in a series of at least three weekly blog posts. Each post will explain one of the problems facing P1144 “std::is_trivially_relocatable” and P2786R0 “Trivial relocatability options” as we try to (1) resolve their technical differences and (2) convince the rest of the C++ Committee that these resolutions are actually okay to ship. Today’s topic is trivial swapping.