Rust 1.17 regression, rotor-stream 0.6.2, private struct constructors

[brson]

brian@ip-10-145-43-250:~/dev/rotor-stream⟫ cargo +stable test
   Compiling winapi v0.2.8
   Compiling bitflags v0.3.3
   Compiling httparse v1.2.2
   Compiling void v1.0.2
   Compiling bytes v0.3.0
   Compiling slab v0.1.3
   Compiling netbuf v0.3.8
   Compiling winapi-build v0.1.1
   Compiling bitflags v0.4.0
   Compiling argparse v0.2.1
   Compiling ws2_32-sys v0.2.1
   Compiling log v0.3.7
   Compiling regex-syntax v0.3.9
   Compiling utf8-ranges v0.1.3
   Compiling quick-error v0.2.2
   Compiling cfg-if v0.1.0
   Compiling libc v0.1.12
   Compiling libc v0.2.22
   Compiling nix v0.4.3
   Compiling kernel32-sys v0.2.2
   Compiling net2 v0.2.29
   Compiling memchr v0.1.11
   Compiling nix v0.5.1
   Compiling miow v0.1.5
   Compiling thread-id v2.0.0
   Compiling time v0.1.37
   Compiling aho-corasick v0.5.3
   Compiling thread_local v0.2.7
   Compiling regex v0.1.80
   Compiling mio v0.5.1
   Compiling rotor v0.6.3
   Compiling rotor-tools v0.3.2
   Compiling rotor-stream v0.6.2 (file:///mnt2/dev/rotor-stream)
warning: unused import: `std::error::Error`
 --> src/persistent.rs:2:5
  |
2 | use std::error::Error;
  |     ^^^^^^^^^^^^^^^^^
  |
  = note: #[warn(unused_imports)] on by default

error: private struct constructors are not usable through reexports in outer modules
   --> src/persistent.rs:242:13
    |
242 |             Persistent(self.0.clone(), self.1.clone(), Fsm::Idle)
    |             ^^^^^^^^^^
    |
    = note: #[deny(legacy_constructor_visibility)] on by default
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #39207 <https://github.com/rust-lang/rust/issues/39207>

error: aborting due to previous error

error: Could not compile `rotor-stream`.
Build failed, waiting for other jobs to finish...
error: build failed

Presumably this is expected breakage. cc @tailhook

[tailhook]

Yes, this is expected breakage. It was discussed in #38932. While this one is easy to fix, there are other issues with new rust or some other dependency, so I'm not going to spend time on that. Basically, the project is abandoned.

[nagisa]

Closing as expected breakage. Also acknowledged by the crate author.