[apasel422]

Using these traits in an object context previously resulted in an RFC 1214 warning.

[rust-highfive]

r? @alexcrichton

(rust_highfive has picked a reviewer for you, use r? to override)

[apasel422]

It's unclear if this should be labeled [breaking-change], though it probably should be out of caution.

[alexcrichton]

I think I kinda forget what the warnings are here, but what does the warning look like? I'm a little surprised that we'd have to go through and add this explicitly everywhere, but perhaps that's what we settled on?

[apasel422]

"Case 1" mentioned in RFC 1214 seems to imply that this will eventually be necessary, even if it isn't enforced by the compiler right now.

My intuition is that if Clone: Sized, then Default etc. should also be. #27641 added a number of these bounds. Maybe @nikomatsakis can clarify if these will be necessary.

[alexcrichton]

Hm ok, I'm a little surprised that these warnings are delayed rather than being emitted on the trait definition itself. For now though this seems fine, so I'm gonna r+

@bors: r+ 863bb1f

[bors]

⌛ Testing commit 863bb1f with merge 2a41821...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-debug-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-linux-cross-opt, auto-linux-musl-64-opt, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-gnu-32-nopt-t, auto-win-gnu-32-opt, auto-win-gnu-64-nopt-t, auto-win-gnu-64-opt, auto-win-msvc-32-opt, auto-win-msvc-64-opt