[INFO] fetching crate ramp 0.6.0...
[INFO] testing ramp-0.6.0 against 1.54.0 for beta-1.55-1
[INFO] extracting crate ramp 0.6.0 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate ramp 0.6.0 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 ramp 0.6.0
[INFO] finished tweaking crates.io crate ramp 0.6.0
[INFO] tweaked toml for crates.io crate ramp 0.6.0 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate crates.io crate ramp 0.6.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.54.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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] 4f8432dc9ec538f088b6f3d2c59dcf1b4980edfe8988ab4d6c37dd461da67fb6
[INFO] running `Command { std: "docker" "start" "-a" "4f8432dc9ec538f088b6f3d2c59dcf1b4980edfe8988ab4d6c37dd461da67fb6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4f8432dc9ec538f088b6f3d2c59dcf1b4980edfe8988ab4d6c37dd461da67fb6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4f8432dc9ec538f088b6f3d2c59dcf1b4980edfe8988ab4d6c37dd461da67fb6", kill_on_drop: false }`
[INFO] [stdout] 4f8432dc9ec538f088b6f3d2c59dcf1b4980edfe8988ab4d6c37dd461da67fb6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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] 262dbe9ce5d44aff3824206468a3edc2301bcb28241808ac0ea8a2427bec702d
[INFO] running `Command { std: "docker" "start" "-a" "262dbe9ce5d44aff3824206468a3edc2301bcb28241808ac0ea8a2427bec702d", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.95
[INFO] [stderr]    Compiling proc-macro2 v1.0.27
[INFO] [stderr]    Compiling syn v1.0.72
[INFO] [stderr]    Compiling cc v1.0.68
[INFO] [stderr]    Compiling gimli v0.24.0
[INFO] [stderr]    Compiling object v0.24.0
[INFO] [stderr]    Compiling rustc-demangle v0.1.19
[INFO] [stderr]    Compiling ieee754 v0.2.2
[INFO] [stderr]    Compiling hamming v0.1.3
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.4.0
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling backtrace v0.3.59
[INFO] [stderr]    Compiling getrandom v0.2.3
[INFO] [stderr]    Compiling rand_core v0.6.2
[INFO] [stderr]    Compiling rand_chacha v0.3.0
[INFO] [stderr]    Compiling rand v0.8.3
[INFO] [stderr]    Compiling addr2line v0.15.1
[INFO] [stderr]    Compiling synstructure v0.12.4
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling failure v0.1.8
[INFO] [stderr]    Compiling rustc-cfg v0.4.0
[INFO] [stderr]    Compiling ramp v0.6.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:17:1
[INFO] [stdout]    |
[INFO] [stdout] 17 | #![feature(core_intrinsics, asm, allocator_api)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:18:1
[INFO] [stdout]    |
[INFO] [stdout] 18 | #![feature(step_trait, ptr_internals, raw_vec_internals)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ramp`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "262dbe9ce5d44aff3824206468a3edc2301bcb28241808ac0ea8a2427bec702d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "262dbe9ce5d44aff3824206468a3edc2301bcb28241808ac0ea8a2427bec702d", kill_on_drop: false }`
[INFO] [stdout] 262dbe9ce5d44aff3824206468a3edc2301bcb28241808ac0ea8a2427bec702d
