[INFO] fetching crate skip 0.0.0...
[INFO] testing skip-0.0.0 against 1.75.0 for beta-1.76-1
[INFO] extracting crate skip 0.0.0 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate skip 0.0.0 on toolchain 1.75.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate skip 0.0.0
[INFO] finished tweaking crates.io crate skip 0.0.0
[INFO] tweaked toml for crates.io crate skip 0.0.0 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.75.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f59907225c55e709e077bed602f67d96ba6abc8c1041e8e2ed73dbad2405a55c
[INFO] running `Command { std: "docker" "start" "-a" "f59907225c55e709e077bed602f67d96ba6abc8c1041e8e2ed73dbad2405a55c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f59907225c55e709e077bed602f67d96ba6abc8c1041e8e2ed73dbad2405a55c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f59907225c55e709e077bed602f67d96ba6abc8c1041e8e2ed73dbad2405a55c", kill_on_drop: false }`
[INFO] [stdout] f59907225c55e709e077bed602f67d96ba6abc8c1041e8e2ed73dbad2405a55c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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=warn" "-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+1.75.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 196ec74321c1dde98d4504a5e273652867d320b78548ea80399d6ac662663dd5
[INFO] running `Command { std: "docker" "start" "-a" "196ec74321c1dde98d4504a5e273652867d320b78548ea80399d6ac662663dd5", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling rand_core v0.4.2
[INFO] [stderr]    Compiling libc v0.2.151
[INFO] [stderr]    Compiling rand_core v0.3.1
[INFO] [stderr]    Compiling rand_jitter v0.1.4
[INFO] [stderr]    Compiling autocfg v0.1.8
[INFO] [stderr]    Compiling rand_xorshift v0.1.1
[INFO] [stderr]    Compiling rand_hc v0.1.0
[INFO] [stderr]    Compiling rand_isaac v0.1.1
[INFO] [stderr]    Compiling rand_pcg v0.1.2
[INFO] [stderr]    Compiling rand_chacha v0.1.1
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling skip v0.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(box_into_raw_non_null)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0635]: unknown feature `box_into_raw_non_null`
[INFO] [stdout]  --> src/lib.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(box_into_raw_non_null)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no function or associated item named `into_raw_non_null` found for struct `Box<_, _>` in the current scope
[INFO] [stdout]   --> src/lib.rs:86:33
[INFO] [stdout]    |
[INFO] [stdout] 86 |         let new_node_ptr = Box::into_raw_non_null(new_node);
[INFO] [stdout]    |                                 ^^^^^^^^^^^^^^^^^ function or associated item not found in `Box<_, _>`
[INFO] [stdout]    |
[INFO] [stdout] note: if you're trying to build a new `Box<_, _>` consider using one of the following associated functions:
[INFO] [stdout]       Box::<T>::new
[INFO] [stdout]       Box::<T>::new_uninit
[INFO] [stdout]       Box::<T>::new_zeroed
[INFO] [stdout]       Box::<T>::try_new
[INFO] [stdout]       and 18 others
[INFO] [stdout]   --> /rustc/82e1608dfa6e0b5569232559e3d385fea5a93112/library/alloc/src/boxed.rs:215:5
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0599, E0635.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `skip` (lib) due to 4 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "196ec74321c1dde98d4504a5e273652867d320b78548ea80399d6ac662663dd5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "196ec74321c1dde98d4504a5e273652867d320b78548ea80399d6ac662663dd5", kill_on_drop: false }`
[INFO] [stdout] 196ec74321c1dde98d4504a5e273652867d320b78548ea80399d6ac662663dd5
