[INFO] cloning repository https://github.com/martin-t/sokoban-solver
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/martin-t/sokoban-solver" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmartin-t%2Fsokoban-solver", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmartin-t%2Fsokoban-solver'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 625b5fa32cfec4f1673cb8a3d3d1c1325e400b6a
[INFO] testing martin-t/sokoban-solver against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmartin-t%2Fsokoban-solver" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/martin-t/sokoban-solver on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/martin-t/sokoban-solver
[INFO] finished tweaking git repo https://github.com/martin-t/sokoban-solver
[INFO] tweaked toml for git repo https://github.com/martin-t/sokoban-solver written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/martin-t/sokoban-solver already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 6da060393978c7dd416d7227cd5a5123ad0bbd8c2aeb9838595c66cc64834e08
[INFO] running `Command { std: "docker" "start" "-a" "6da060393978c7dd416d7227cd5a5123ad0bbd8c2aeb9838595c66cc64834e08", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6da060393978c7dd416d7227cd5a5123ad0bbd8c2aeb9838595c66cc64834e08", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6da060393978c7dd416d7227cd5a5123ad0bbd8c2aeb9838595c66cc64834e08", kill_on_drop: false }`
[INFO] [stdout] 6da060393978c7dd416d7227cd5a5123ad0bbd8c2aeb9838595c66cc64834e08
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "rustops/crates-build-env@sha256:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] dfcbe33e6952d676daae0cf70b99debbdb2bce70b78dd589d792d4ed733094b8
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "dfcbe33e6952d676daae0cf70b99debbdb2bce70b78dd589d792d4ed733094b8", kill_on_drop: false }`
[INFO] [stderr]    Compiling lazy_static v1.4.0
[INFO] [stderr]    Compiling regex-syntax v0.6.21
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling unicode-width v0.1.8
[INFO] [stderr]    Compiling humantime v2.0.1
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling ansi_term v0.11.0
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling termcolor v1.1.2
[INFO] [stderr]    Compiling fnv v1.0.7
[INFO] [stderr]    Compiling typed-arena v2.0.1
[INFO] [stderr]    Compiling separator v0.4.1
[INFO] [stderr]    Compiling memchr v2.3.4
[INFO] [stderr]    Compiling libc v0.2.81
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]    Compiling thread_local v1.0.1
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling aho-corasick v0.7.15
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling regex v1.4.2
[INFO] [stderr]    Compiling env_logger v0.8.2
[INFO] [stderr]    Compiling sokoban-solver 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:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(crate_visibility_modifier)]
[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:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(min_specialization)]
[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:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(stmt_expr_attributes)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 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 `sokoban-solver`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "dfcbe33e6952d676daae0cf70b99debbdb2bce70b78dd589d792d4ed733094b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dfcbe33e6952d676daae0cf70b99debbdb2bce70b78dd589d792d4ed733094b8", kill_on_drop: false }`
[INFO] [stdout] dfcbe33e6952d676daae0cf70b99debbdb2bce70b78dd589d792d4ed733094b8