[INFO] cloning repository https://github.com/sprengvogel/rust-collatz
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sprengvogel/rust-collatz" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsprengvogel%2Frust-collatz", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsprengvogel%2Frust-collatz'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3f652b6e330212961dbbb905adf49d856155107f
[INFO] checking sprengvogel/rust-collatz against try#ddfd70ee3c3748e597b32f416b0d15a4f6e37685 for pr-87050
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsprengvogel%2Frust-collatz" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sprengvogel/rust-collatz on toolchain ddfd70ee3c3748e597b32f416b0d15a4f6e37685
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/sprengvogel/rust-collatz
[INFO] finished tweaking git repo https://github.com/sprengvogel/rust-collatz
[INFO] tweaked toml for git repo https://github.com/sprengvogel/rust-collatz written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/sprengvogel/rust-collatz already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 730b123f8a3ad630ae87c20ac5ed96f89abf1ecbfa059390a2d3bf180005c985
[INFO] running `Command { std: "docker" "start" "-a" "730b123f8a3ad630ae87c20ac5ed96f89abf1ecbfa059390a2d3bf180005c985", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "730b123f8a3ad630ae87c20ac5ed96f89abf1ecbfa059390a2d3bf180005c985", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "730b123f8a3ad630ae87c20ac5ed96f89abf1ecbfa059390a2d3bf180005c985", kill_on_drop: false }`
[INFO] [stdout] 730b123f8a3ad630ae87c20ac5ed96f89abf1ecbfa059390a2d3bf180005c985
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+ddfd70ee3c3748e597b32f416b0d15a4f6e37685" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4671146f8dfc98f2ce986150ca5609d84dfa599c919b221a1ea96d6ec19f1e9f
[INFO] running `Command { std: "docker" "start" "-a" "4671146f8dfc98f2ce986150ca5609d84dfa599c919b221a1ea96d6ec19f1e9f", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.6
[INFO] [stderr]    Compiling num-integer v0.1.39
[INFO] [stderr]    Compiling num-bigint v0.2.1
[INFO] [stderr]    Compiling num-complex v0.2.1
[INFO] [stderr]    Compiling num-iter v0.1.37
[INFO] [stderr]    Compiling num-rational v0.2.1
[INFO] [stderr]     Checking num v0.2.0
[INFO] [stderr]     Checking collatz v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function is never used: `do_collatz_without_overflow_check`
[INFO] [stdout]   --> src/main.rs:58:4
[INFO] [stdout]    |
[INFO] [stdout] 58 | fn do_collatz_without_overflow_check(mut x: u64) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `do_collatz_with_bigints`
[INFO] [stdout]   --> src/main.rs:75:4
[INFO] [stdout]    |
[INFO] [stdout] 75 | fn do_collatz_with_bigints(mut x: BigUint) {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 8.31s
[INFO] running `Command { std: "docker" "inspect" "4671146f8dfc98f2ce986150ca5609d84dfa599c919b221a1ea96d6ec19f1e9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4671146f8dfc98f2ce986150ca5609d84dfa599c919b221a1ea96d6ec19f1e9f", kill_on_drop: false }`
[INFO] [stdout] 4671146f8dfc98f2ce986150ca5609d84dfa599c919b221a1ea96d6ec19f1e9f