[INFO] cloning repository https://github.com/brain0/cowbench
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/brain0/cowbench" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrain0%2Fcowbench", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrain0%2Fcowbench'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 6a114c3645e39d61d916258537325903a3fbfbdb
[INFO] testing brain0/cowbench against beta-2021-08-01 for beta-1.55-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbrain0%2Fcowbench" "/workspace/builds/worker-110/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-110/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/brain0/cowbench on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/brain0/cowbench
[INFO] finished tweaking git repo https://github.com/brain0/cowbench
[INFO] tweaked toml for git repo https://github.com/brain0/cowbench written to /workspace/builds/worker-110/source/Cargo.toml
[INFO] crate git repo https://github.com/brain0/cowbench already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "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-110/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-110/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" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7bfb2a9dd79dbdc62fd6e491e401f2ac30d7cba6cbdced00fdbc352f7036a6cf
[INFO] running `Command { std: "docker" "start" "-a" "7bfb2a9dd79dbdc62fd6e491e401f2ac30d7cba6cbdced00fdbc352f7036a6cf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7bfb2a9dd79dbdc62fd6e491e401f2ac30d7cba6cbdced00fdbc352f7036a6cf", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7bfb2a9dd79dbdc62fd6e491e401f2ac30d7cba6cbdced00fdbc352f7036a6cf", kill_on_drop: false }`
[INFO] [stdout] 7bfb2a9dd79dbdc62fd6e491e401f2ac30d7cba6cbdced00fdbc352f7036a6cf
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-110/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-110/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" "+beta-2021-08-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a17097f858f468b0608bc28effe622f8e872b120faa4c3aeceb8c620e30bf25e
[INFO] running `Command { std: "docker" "start" "-a" "a17097f858f468b0608bc28effe622f8e872b120faa4c3aeceb8c620e30bf25e", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.67
[INFO] [stderr]    Compiling ppv-lite86 v0.2.6
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling cowbench v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(test)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'bench_black_box'
[INFO] [stdout]   --> src/main.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     std::hint::black_box(s);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #64102 <https://github.com/rust-lang/rust/issues/64102> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0658]: use of unstable library feature 'bench_black_box'
[INFO] [stdout]   --> src/main.rs:52:5
[INFO] [stdout]    |
[INFO] [stdout] 52 |     std::hint::black_box(s);
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: see issue #64102 <https://github.com/rust-lang/rust/issues/64102> 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 `cowbench` due to 4 previous errors
[INFO] running `Command { std: "docker" "inspect" "a17097f858f468b0608bc28effe622f8e872b120faa4c3aeceb8c620e30bf25e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a17097f858f468b0608bc28effe622f8e872b120faa4c3aeceb8c620e30bf25e", kill_on_drop: false }`
[INFO] [stdout] a17097f858f468b0608bc28effe622f8e872b120faa4c3aeceb8c620e30bf25e
