[INFO] cloning repository https://github.com/1000teslas/ackermann
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/1000teslas/ackermann" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F1000teslas%2Fackermann", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F1000teslas%2Fackermann'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] efb93d34d31d3e9dde3df526daf5e84699daad99
[INFO] checking 1000teslas/ackermann against try#b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b for pr-82781
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2F1000teslas%2Fackermann" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/1000teslas/ackermann on toolchain b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/1000teslas/ackermann
[INFO] finished tweaking git repo https://github.com/1000teslas/ackermann
[INFO] tweaked toml for git repo https://github.com/1000teslas/ackermann written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/1000teslas/ackermann already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "fetch" "--locked" "--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-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 19784138b17735855b9ba7f67bd9a39ab6ee6ada2f50785313c3fa1b97ba8478
[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" "19784138b17735855b9ba7f67bd9a39ab6ee6ada2f50785313c3fa1b97ba8478", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "19784138b17735855b9ba7f67bd9a39ab6ee6ada2f50785313c3fa1b97ba8478", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "19784138b17735855b9ba7f67bd9a39ab6ee6ada2f50785313c3fa1b97ba8478", kill_on_drop: false }`
[INFO] [stdout] 19784138b17735855b9ba7f67bd9a39ab6ee6ada2f50785313c3fa1b97ba8478
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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=forbid" "-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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7cabc67202e257e08f5305e5541e1955ddf3fdbb12c590b48bf8f086ee86db85
[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" "7cabc67202e257e08f5305e5541e1955ddf3fdbb12c590b48bf8f086ee86db85", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]    Compiling serde v1.0.116
[INFO] [stderr]    Compiling libc v0.2.79
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling memchr v2.3.3
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling serde_json v1.0.59
[INFO] [stderr]    Compiling syn v1.0.44
[INFO] [stderr]    Compiling serde_derive v1.0.116
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]     Checking regex-syntax v0.6.20
[INFO] [stderr]     Checking half v1.6.0
[INFO] [stderr]     Checking ackermann v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]    Compiling crossbeam-utils v0.7.2
[INFO] [stderr]    Compiling memoffset v0.5.6
[INFO] [stderr]    Compiling crossbeam-epoch v0.8.2
[INFO] [stdout] warning: function is never used: `a2`
[INFO] [stdout]  --> src/lib.rs:9:4
[INFO] [stdout]   |
[INFO] [stdout] 9 | fn a2(m: u64, n: u64) -> u64 {
[INFO] [stdout]   |    ^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rayon v1.4.1
[INFO] [stderr]     Checking itertools v0.9.0
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stdout] error[E0432]: unresolved import `scratch`
[INFO] [stdout]  --> src/main.rs:1:5
[INFO] [stdout]   |
[INFO] [stdout] 1 | use scratch::{a_rec, a_iter};
[INFO] [stdout]   |     ^^^^^^^ use of undeclared crate or module `scratch`
[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 E0432`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `ackermann`
[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" "7cabc67202e257e08f5305e5541e1955ddf3fdbb12c590b48bf8f086ee86db85", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7cabc67202e257e08f5305e5541e1955ddf3fdbb12c590b48bf8f086ee86db85", kill_on_drop: false }`
[INFO] [stdout] 7cabc67202e257e08f5305e5541e1955ddf3fdbb12c590b48bf8f086ee86db85