[INFO] fetching crate flatten 0.2.2...
[INFO] checking flatten-0.2.2 against master#3aedcf06b73fc36feeebca3d579e1d2a6c40acc5 for pr-65819
[INFO] extracting crate flatten 0.2.2 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate flatten 0.2.2 on toolchain 3aedcf06b73fc36feeebca3d579e1d2a6c40acc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[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-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "fetch" "--locked" "--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-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c3ce3eab65758da75f3c625bcd8de1ae217b31d50b49c7f245349512f9405985
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "c3ce3eab65758da75f3c625bcd8de1ae217b31d50b49c7f245349512f9405985", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c3ce3eab65758da75f3c625bcd8de1ae217b31d50b49c7f245349512f9405985", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c3ce3eab65758da75f3c625bcd8de1ae217b31d50b49c7f245349512f9405985", kill_on_drop: false }`
[INFO] [stdout] c3ce3eab65758da75f3c625bcd8de1ae217b31d50b49c7f245349512f9405985
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "RUSTFLAGS=--cap-lints=forbid" "-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" "rustops/crates-build-env@sha256:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+3aedcf06b73fc36feeebca3d579e1d2a6c40acc5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 514bec349b800fb9f38ff7ab844c37da7c5e7d35c6ebf402f29424a4fefcfb6f
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "514bec349b800fb9f38ff7ab844c37da7c5e7d35c6ebf402f29424a4fefcfb6f", kill_on_drop: false }`
[INFO] [stderr] warning: `default-features = [".."]` was found in [features]. Did you mean to use `default = [".."]`?
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking either v1.6.1
[INFO] [stderr]     Checking 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[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[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]    = help: add `#![feature(auto_traits)]` to the crate attributes to enable
[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]    = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]    = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]     = help: add `#![feature(auto_traits)]` to the crate attributes to enable
[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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 248 | / impl_for_tuple! {
[INFO] [stdout] 249 | |    (0, A),
[INFO] [stdout] 250 | |    (1, B),
[INFO] [stdout] 251 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 253 | / impl_for_tuple! {
[INFO] [stdout] 254 | |    (0, A),
[INFO] [stdout] 255 | |    (1, B),
[INFO] [stdout] 256 | |    (2, C),
[INFO] [stdout] 257 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 259 | / impl_for_tuple! {
[INFO] [stdout] 260 | |    (0, A),
[INFO] [stdout] 261 | |    (1, B),
[INFO] [stdout] 262 | |    (2, C),
[INFO] [stdout] 263 | |    (3, D),
[INFO] [stdout] 264 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 266 | / impl_for_tuple! {
[INFO] [stdout] 267 | |    (0, A),
[INFO] [stdout] 268 | |    (1, B),
[INFO] [stdout] 269 | |    (2, C),
[INFO] [stdout] 270 | |    (3, D),
[INFO] [stdout] 271 | |    (4, E),
[INFO] [stdout] 272 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 274 | / impl_for_tuple! {
[INFO] [stdout] 275 | |    (0, A),
[INFO] [stdout] 276 | |    (1, B),
[INFO] [stdout] 277 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 280 | |    (5, F),
[INFO] [stdout] 281 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 283 | / impl_for_tuple! {
[INFO] [stdout] 284 | |    (0, A),
[INFO] [stdout] 285 | |    (1, B),
[INFO] [stdout] 286 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 290 | |    (6, G),
[INFO] [stdout] 291 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 293 | / impl_for_tuple! {
[INFO] [stdout] 294 | |    (0, A),
[INFO] [stdout] 295 | |    (1, B),
[INFO] [stdout] 296 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 301 | |    (7, H),
[INFO] [stdout] 302 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 304 | / impl_for_tuple! {
[INFO] [stdout] 305 | |    (0, A),
[INFO] [stdout] 306 | |    (1, B),
[INFO] [stdout] 307 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 313 | |    (8, I),
[INFO] [stdout] 314 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 316 | / impl_for_tuple! {
[INFO] [stdout] 317 | |    (0, A),
[INFO] [stdout] 318 | |    (1, B),
[INFO] [stdout] 319 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 326 | |    (9, J),
[INFO] [stdout] 327 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 329 | / impl_for_tuple! {
[INFO] [stdout] 330 | |    (0, A),
[INFO] [stdout] 331 | |    (1, B),
[INFO] [stdout] 332 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 340 | |    (10, K),
[INFO] [stdout] 341 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (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]    = help: add `#![feature(rustc_attrs)]` to the crate attributes to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:64
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(optin_builtin_traits, on_unimplemented, never_type, specialization)]
[INFO] [stdout]   |                                                                ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]    --> src/into_cons.rs:234:21
[INFO] [stdout]     |
[INFO] [stdout] 234 |                       ( $( $N ),* )
[INFO] [stdout]     |                       ^^^^^^^^^^^^^ help: remove these parentheses
[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: `#[warn(unused_parens)]` on by default
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/tuple.rs:185:9
[INFO] [stdout]     |
[INFO] [stdout] 185 |         (self.head)
[INFO] [stdout]     |         ^^^^^^^^^^^ help: remove these parentheses
[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]    = help: add `#![feature(auto_traits)]` to the crate attributes to enable
[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]    = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]    = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]     = help: add `#![feature(auto_traits)]` to the crate attributes to enable
[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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[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, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 248 | / impl_for_tuple! {
[INFO] [stdout] 249 | |    (0, A),
[INFO] [stdout] 250 | |    (1, B),
[INFO] [stdout] 251 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 253 | / impl_for_tuple! {
[INFO] [stdout] 254 | |    (0, A),
[INFO] [stdout] 255 | |    (1, B),
[INFO] [stdout] 256 | |    (2, C),
[INFO] [stdout] 257 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 259 | / impl_for_tuple! {
[INFO] [stdout] 260 | |    (0, A),
[INFO] [stdout] 261 | |    (1, B),
[INFO] [stdout] 262 | |    (2, C),
[INFO] [stdout] 263 | |    (3, D),
[INFO] [stdout] 264 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 266 | / impl_for_tuple! {
[INFO] [stdout] 267 | |    (0, A),
[INFO] [stdout] 268 | |    (1, B),
[INFO] [stdout] 269 | |    (2, C),
[INFO] [stdout] 270 | |    (3, D),
[INFO] [stdout] 271 | |    (4, E),
[INFO] [stdout] 272 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 274 | / impl_for_tuple! {
[INFO] [stdout] 275 | |    (0, A),
[INFO] [stdout] 276 | |    (1, B),
[INFO] [stdout] 277 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 280 | |    (5, F),
[INFO] [stdout] 281 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 283 | / impl_for_tuple! {
[INFO] [stdout] 284 | |    (0, A),
[INFO] [stdout] 285 | |    (1, B),
[INFO] [stdout] 286 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 290 | |    (6, G),
[INFO] [stdout] 291 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 293 | / impl_for_tuple! {
[INFO] [stdout] 294 | |    (0, A),
[INFO] [stdout] 295 | |    (1, B),
[INFO] [stdout] 296 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 301 | |    (7, H),
[INFO] [stdout] 302 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 304 | / impl_for_tuple! {
[INFO] [stdout] 305 | |    (0, A),
[INFO] [stdout] 306 | |    (1, B),
[INFO] [stdout] 307 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 313 | |    (8, I),
[INFO] [stdout] 314 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 316 | / impl_for_tuple! {
[INFO] [stdout] 317 | |    (0, A),
[INFO] [stdout] 318 | |    (1, B),
[INFO] [stdout] 319 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 326 | |    (9, J),
[INFO] [stdout] 327 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$first_ty, $( $N ),*> !NotTuple for ( $first_ty, $( $N, )* ) {}
[INFO] [stdout]     |                                      ^^^^^^^^^
[INFO] [stdout] ...
[INFO] [stdout] 329 | / impl_for_tuple! {
[INFO] [stdout] 330 | |    (0, A),
[INFO] [stdout] 331 | |    (1, B),
[INFO] [stdout] 332 | |    (2, C),
[INFO] [stdout] ...   |
[INFO] [stdout] 340 | |    (10, K),
[INFO] [stdout] 341 | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #68318 <https://github.com/rust-lang/rust/issues/68318> for more information
[INFO] [stdout]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: negative trait bounds are not yet fully implemented; use marker types for now
[INFO] [stdout]    --> src/into_cons.rs:218:36
[INFO] [stdout]     |
[INFO] [stdout] 218 |           impl<$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]     = help: add `#![feature(negative_impls)]` to the crate attributes to enable
[INFO] [stdout]     = note: this error originates in a macro (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]    = help: add `#![feature(rustc_attrs)]` to the crate attributes to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/lib.rs:1:64
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(optin_builtin_traits, on_unimplemented, never_type, specialization)]
[INFO] [stdout]   |                                                                ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout]   = help: consider using `min_specialization` instead, which is more stable and complete
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]    --> src/into_cons.rs:234:21
[INFO] [stdout]     |
[INFO] [stdout] 234 |                       ( $( $N ),* )
[INFO] [stdout]     |                       ^^^^^^^^^^^^^ help: remove these parentheses
[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: `#[warn(unused_parens)]` on by default
[INFO] [stdout]     = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/tuple.rs:185:9
[INFO] [stdout]     |
[INFO] [stdout] 185 |         (self.head)
[INFO] [stdout]     |         ^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the trait bound `cons::Cons<V, cons::Nil>: FixHead` is not satisfied
[INFO] [stdout]    --> src/into_cons.rs:148:5
[INFO] [stdout]     |
[INFO] [stdout] 81  |     type Specialized: From<Self> + SpecializedIntoCons;
[INFO] [stdout]     |                                    ------------------- required by this bound in `IntoConsSpecializer::Specialized`
[INFO] [stdout] ...
[INFO] [stdout] 148 |     default type Specialized = DefaultIntoCons<Self>;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `FixHead` is not implemented for `cons::Cons<V, cons::Nil>`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because of the requirements on the impl of `SpecializedIntoCons` for `DefaultIntoCons<V>`
[INFO] [stdout] help: consider introducing a `where` bound, but there might be an alternative better way to express this requirement
[INFO] [stdout]     |
[INFO] [stdout] 147 | impl<V> IntoConsSpecializer for V where cons::Cons<V, cons::Nil>: FixHead {
[INFO] [stdout]     |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0277]: the trait bound `cons::Cons<V, cons::Nil>: FixHead` is not satisfied
[INFO] [stdout]    --> src/into_cons.rs:148:5
[INFO] [stdout]     |
[INFO] [stdout] 81  |     type Specialized: From<Self> + SpecializedIntoCons;
[INFO] [stdout]     |                                    ------------------- required by this bound in `IntoConsSpecializer::Specialized`
[INFO] [stdout] ...
[INFO] [stdout] 148 |     default type Specialized = DefaultIntoCons<Self>;
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `FixHead` is not implemented for `cons::Cons<V, cons::Nil>`
[INFO] [stdout]     |
[INFO] [stdout]     = note: required because of the requirements on the impl of `SpecializedIntoCons` for `DefaultIntoCons<V>`
[INFO] [stdout] help: consider introducing a `where` bound, but there might be an alternative better way to express this requirement
[INFO] [stdout]     |
[INFO] [stdout] 147 | impl<V> IntoConsSpecializer for V where cons::Cons<V, cons::Nil>: FixHead {
[INFO] [stdout]     |                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 22 previous errors; 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0557, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 22 previous errors; 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0277, E0557, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0277`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `flatten`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "514bec349b800fb9f38ff7ab844c37da7c5e7d35c6ebf402f29424a4fefcfb6f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "514bec349b800fb9f38ff7ab844c37da7c5e7d35c6ebf402f29424a4fefcfb6f", kill_on_drop: false }`
[INFO] [stdout] 514bec349b800fb9f38ff7ab844c37da7c5e7d35c6ebf402f29424a4fefcfb6f