[INFO] fetching crate slaballoc 0.1.0...
[INFO] testing slaballoc-0.1.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate slaballoc 0.1.0 into /workspace/builds/worker-13/source
[INFO] validating manifest of crates.io crate slaballoc 0.1.0 on toolchain 1.54.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate slaballoc 0.1.0
[INFO] finished tweaking crates.io crate slaballoc 0.1.0
[INFO] tweaked toml for crates.io crate slaballoc 0.1.0 written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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" "+1.54.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b4fcd48417d3f2693ad98b451218b0a6daf9c0b33d93a53dc0d59549931ebb4b
[INFO] running `Command { std: "docker" "start" "-a" "b4fcd48417d3f2693ad98b451218b0a6daf9c0b33d93a53dc0d59549931ebb4b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b4fcd48417d3f2693ad98b451218b0a6daf9c0b33d93a53dc0d59549931ebb4b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b4fcd48417d3f2693ad98b451218b0a6daf9c0b33d93a53dc0d59549931ebb4b", kill_on_drop: false }`
[INFO] [stdout] b4fcd48417d3f2693ad98b451218b0a6daf9c0b33d93a53dc0d59549931ebb4b
[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" "RUSTFLAGS=--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" "+1.54.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d6f9b0851ab1ed48e96d7989d17e9dc6ff4c4c7068b468b887d5aa14ee27213c
[INFO] running `Command { std: "docker" "start" "-a" "d6f9b0851ab1ed48e96d7989d17e9dc6ff4c4c7068b468b887d5aa14ee27213c", kill_on_drop: false }`
[INFO] [stderr]    Compiling slaballoc v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(allocator_api, maybe_uninit_slice)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'maybe_uninit_extra'
[INFO] [stdout]   --> src/slab.rs:93:19
[INFO] [stdout]    |
[INFO] [stdout] 93 |                 b.write(AtomicU8::new(0));
[INFO] [stdout]    |                   ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #63567 <https://github.com/rust-lang/rust/issues/63567> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'maybe_uninit_ref'
[INFO] [stdout]    --> src/slab.rs:147:15
[INFO] [stdout]     |
[INFO] [stdout] 147 |             e.assume_init_mut()
[INFO] [stdout]     |               ^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: see issue #63568 <https://github.com/rust-lang/rust/issues/63568> for more information
[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, E0658.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `slaballoc`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "d6f9b0851ab1ed48e96d7989d17e9dc6ff4c4c7068b468b887d5aa14ee27213c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d6f9b0851ab1ed48e96d7989d17e9dc6ff4c4c7068b468b887d5aa14ee27213c", kill_on_drop: false }`
[INFO] [stdout] d6f9b0851ab1ed48e96d7989d17e9dc6ff4c4c7068b468b887d5aa14ee27213c
