MSRV 1.56.0 TODO

[asomers]

After raising the MSRV to 1.56.0:

• Simplify ipv4addr_to_libc and ipv4addr_to_libc by changing their bodies to a simple mem::transmute, since Ipv4Addr and Ipv6Addr are simple newtypes around the libc types.

[rtzoeller]

Is std::mem::transmute sound for std::net::Ipv4Addr? It isn't marked repr(transparent).

[asomers]

If we have a static_assertion that guarantees that Ipv4Addr and libc::sockaddr_in are the same size, then it's safe, right? That was my plan.

[rtzoeller]

I believe that should be fine.