[INFO] fetching crate cargo-minicov 0.1.2...
[INFO] testing cargo-minicov-0.1.2 against beta-2021-09-08 for beta-1.56-1
[INFO] extracting crate cargo-minicov 0.1.2 into /workspace/builds/worker-59/source
[INFO] validating manifest of crates.io crate cargo-minicov 0.1.2 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate cargo-minicov 0.1.2
[INFO] finished tweaking crates.io crate cargo-minicov 0.1.2
[INFO] tweaked toml for crates.io crate cargo-minicov 0.1.2 written to /workspace/builds/worker-59/source/Cargo.toml
[INFO] crate crates.io crate cargo-minicov 0.1.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-59/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-59/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 52b9d11b9a623b5d7087abdd5a3d8ec7e5fd7c98cfd5fdb9e7fe79ea0296e06d
[INFO] running `Command { std: "docker" "start" "-a" "52b9d11b9a623b5d7087abdd5a3d8ec7e5fd7c98cfd5fdb9e7fe79ea0296e06d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "52b9d11b9a623b5d7087abdd5a3d8ec7e5fd7c98cfd5fdb9e7fe79ea0296e06d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "52b9d11b9a623b5d7087abdd5a3d8ec7e5fd7c98cfd5fdb9e7fe79ea0296e06d", kill_on_drop: false }`
[INFO] [stdout] 52b9d11b9a623b5d7087abdd5a3d8ec7e5fd7c98cfd5fdb9e7fe79ea0296e06d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-59/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-59/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 96b27c2c3d1f021109776637f5b37b4c0d4f0b56632ab60cd31f616f6db5d8a0
[INFO] running `Command { std: "docker" "start" "-a" "96b27c2c3d1f021109776637f5b37b4c0d4f0b56632ab60cd31f616f6db5d8a0", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling version_check v0.9.2
[INFO] [stderr]    Compiling syn v1.0.48
[INFO] [stderr]    Compiling libc v0.2.80
[INFO] [stderr]    Compiling serde_derive v1.0.117
[INFO] [stderr]    Compiling serde v1.0.117
[INFO] [stderr]    Compiling unicode-segmentation v1.7.0
[INFO] [stderr]    Compiling postcard-cobs v0.1.5-pre
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling structopt-derive v0.4.13
[INFO] [stderr]    Compiling structopt v0.3.20
[INFO] [stderr]    Compiling postcard v0.5.1
[INFO] [stderr]    Compiling cargo-minicov v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(profiler_runtime_lib)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `cargo-minicov` due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "96b27c2c3d1f021109776637f5b37b4c0d4f0b56632ab60cd31f616f6db5d8a0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "96b27c2c3d1f021109776637f5b37b4c0d4f0b56632ab60cd31f616f6db5d8a0", kill_on_drop: false }`
[INFO] [stdout] 96b27c2c3d1f021109776637f5b37b4c0d4f0b56632ab60cd31f616f6db5d8a0