[INFO] fetching crate flatten 0.2.2...
[INFO] documenting flatten-0.2.2 against beta-2021-08-01 for beta-1.55-rustdoc-1
[INFO] extracting crate flatten 0.2.2 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate flatten 0.2.2 on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-13/source/rust-toolchain
[INFO] started tweaking crates.io crate flatten 0.2.2
[INFO] finished tweaking crates.io crate flatten 0.2.2
[INFO] tweaked toml for crates.io crate flatten 0.2.2 written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr] warning: `default-features = [".."]` was found in [features]. Did you mean to use `default = [".."]`?
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5272c60439756a6ee08e8a8d4bf77cf19da76ffad3de1ac937e80a3a1206c318
[INFO] running `Command { std: "docker" "start" "-a" "5272c60439756a6ee08e8a8d4bf77cf19da76ffad3de1ac937e80a3a1206c318", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5272c60439756a6ee08e8a8d4bf77cf19da76ffad3de1ac937e80a3a1206c318", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5272c60439756a6ee08e8a8d4bf77cf19da76ffad3de1ac937e80a3a1206c318", kill_on_drop: false }`
[INFO] [stdout] 5272c60439756a6ee08e8a8d4bf77cf19da76ffad3de1ac937e80a3a1206c318
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b7ffdb12a1a5e2085488ab2465806a35011883e2510e0b8870f77ab290046d5d
[INFO] running `Command { std: "docker" "start" "-a" "b7ffdb12a1a5e2085488ab2465806a35011883e2510e0b8870f77ab290046d5d", kill_on_drop: false }`
[INFO] [stderr] warning: `default-features = [".."]` was found in [features]. Did you mean to use `default = [".."]`?
[INFO] [stderr]  Documenting flatten v0.2.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(optin_builtin_traits, on_unimplemented, never_type, specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^ feature has been removed
[INFO] [stdout]   |
[INFO] [stdout]   = note: renamed to `auto_traits`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0557]: feature has been removed
[INFO] [stdout]  --> src/lib.rs:1:34
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(optin_builtin_traits, on_unimplemented, never_type, specialization)]
[INFO] [stdout]   |                                  ^^^^^^^^^^^^^^^^ feature has been removed
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(optin_builtin_traits, on_unimplemented, never_type, specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: auto traits are experimental and possibly buggy
[INFO] [stdout]   --> src/cons/mod.rs:23:1
[INFO] [stdout]    |
[INFO] [stdout] 23 | pub auto trait ValidHead {}
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #13231 <https://github.com/rust-lang/rust/issues/13231> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]   --> src/cons/mod.rs:24:6
[INFO] [stdout]    |
[INFO] [stdout] 24 | impl !ValidHead for Nil {}
[INFO] [stdout]    |      ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]   --> src/cons/mod.rs:25:12
[INFO] [stdout]    |
[INFO] [stdout] 25 | impl<H, T> !ValidHead for Cons<H, T> {}
[INFO] [stdout]    |            ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: auto traits are experimental and possibly buggy
[INFO] [stdout]    --> src/into_cons.rs:152:1
[INFO] [stdout]     |
[INFO] [stdout] 152 | pub auto trait NotTuple {}
[INFO] [stdout]     | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #13231 <https://github.com/rust-lang/rust/issues/13231> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:153:6
[INFO] [stdout]     |
[INFO] [stdout] 153 | impl !NotTuple for () {}
[INFO] [stdout]     |      ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:154:9
[INFO] [stdout]     |
[INFO] [stdout] 154 | impl<A> !NotTuple for (A,) {}
[INFO] [stdout]     |         ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:155:9
[INFO] [stdout]     |
[INFO] [stdout] 155 | impl<R> !NotTuple for Either<!, R> {}
[INFO] [stdout]     |         ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 248 | / impl_for_tuple! {
[INFO] [stdout] 249 | |    (0, A),
[INFO] [stdout] 250 | |    (1, B),
[INFO] [stdout] 251 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 253 | / impl_for_tuple! {
[INFO] [stdout] 254 | |    (0, A),
[INFO] [stdout] 255 | |    (1, B),
[INFO] [stdout] 256 | |    (2, C),
[INFO] [stdout] 257 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 259 | / impl_for_tuple! {
[INFO] [stdout] 260 | |    (0, A),
[INFO] [stdout] 261 | |    (1, B),
[INFO] [stdout] 262 | |    (2, C),
[INFO] [stdout] 263 | |    (3, D),
[INFO] [stdout] 264 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 266 | / impl_for_tuple! {
[INFO] [stdout] 267 | |    (0, A),
[INFO] [stdout] 268 | |    (1, B),
[INFO] [stdout] 269 | |    (2, C),
[INFO] [stdout] 270 | |    (3, D),
[INFO] [stdout] 271 | |    (4, E),
[INFO] [stdout] 272 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 274 | / impl_for_tuple! {
[INFO] [stdout] 275 | |    (0, A),
[INFO] [stdout] 276 | |    (1, B),
[INFO] [stdout] 277 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 280 | |    (5, F),
[INFO] [stdout] 281 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 283 | / impl_for_tuple! {
[INFO] [stdout] 284 | |    (0, A),
[INFO] [stdout] 285 | |    (1, B),
[INFO] [stdout] 286 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 290 | |    (6, G),
[INFO] [stdout] 291 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 293 | / impl_for_tuple! {
[INFO] [stdout] 294 | |    (0, A),
[INFO] [stdout] 295 | |    (1, B),
[INFO] [stdout] 296 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 301 | |    (7, H),
[INFO] [stdout] 302 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 304 | / impl_for_tuple! {
[INFO] [stdout] 305 | |    (0, A),
[INFO] [stdout] 306 | |    (1, B),
[INFO] [stdout] 307 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 313 | |    (8, I),
[INFO] [stdout] 314 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 316 | / impl_for_tuple! {
[INFO] [stdout] 317 | |    (0, A),
[INFO] [stdout] 318 | |    (1, B),
[INFO] [stdout] 319 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 326 | |    (9, J),
[INFO] [stdout] 327 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 329 | / impl_for_tuple! {
[INFO] [stdout] 330 | |    (0, A),
[INFO] [stdout] 331 | |    (1, B),
[INFO] [stdout] 332 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 340 | |    (10, K),
[INFO] [stdout] 341 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 343 | / impl_for_tuple! {
[INFO] [stdout] 344 | |    (0, A),
[INFO] [stdout] 345 | |    (1, B),
[INFO] [stdout] 346 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 355 | |    (11, L),
[INFO] [stdout] 356 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = note: this error originates in the macro `impl_for_tuple` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: this is an internal attribute that will never be stable
[INFO] [stdout]   --> src/tuple.rs:18:1
[INFO] [stdout]    |
[INFO] [stdout] 18 | / #[rustc_on_unimplemented = "
[INFO] [stdout] 19 | | If you are writing generic code, add a bound like
[INFO] [stdout] 20 | |
[INFO] [stdout] 21 | |     where {OrigType}: Flatten,
[INFO] [stdout] ...  |
[INFO] [stdout] 31 | |
[INFO] [stdout] 32 | | This is required because current type system does not have negative reasoning."]
[INFO] [stdout]    | |________________________________________________________________________________^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 23 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0557, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `flatten`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name flatten src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern either=/opt/rustwide/target/debug/deps/libeither-289a99daa7aee5d6.rmeta --cap-lints=warn --crate-version 0.2.2` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "b7ffdb12a1a5e2085488ab2465806a35011883e2510e0b8870f77ab290046d5d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b7ffdb12a1a5e2085488ab2465806a35011883e2510e0b8870f77ab290046d5d", kill_on_drop: false }`
[INFO] [stdout] b7ffdb12a1a5e2085488ab2465806a35011883e2510e0b8870f77ab290046d5d
