[INFO] cloning repository https://github.com/Nalleyer/rust_99_problem
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Nalleyer/rust_99_problem" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FNalleyer%2Frust_99_problem", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FNalleyer%2Frust_99_problem'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 963a80b26b71b2cb375922c8d99b1096e715d0e5
[INFO] checking Nalleyer/rust_99_problem against try#f6e2f78768c57172b99c3e85892f867894dc7e30 for pr-75502
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FNalleyer%2Frust_99_problem" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Nalleyer/rust_99_problem on toolchain f6e2f78768c57172b99c3e85892f867894dc7e30
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Nalleyer/rust_99_problem
[INFO] finished tweaking git repo https://github.com/Nalleyer/rust_99_problem
[INFO] tweaked toml for git repo https://github.com/Nalleyer/rust_99_problem written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/Nalleyer/rust_99_problem already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded env_logger v0.6.1
[INFO] [stderr]   Downloaded quickcheck v0.8.2
[INFO] [stderr]   Downloaded quickcheck_macros v0.8.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 41c89326b0511a0cc589f59835e19f83a25fcffcf3b9fa79cd0c1f15842dc80e
[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" "41c89326b0511a0cc589f59835e19f83a25fcffcf3b9fa79cd0c1f15842dc80e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "41c89326b0511a0cc589f59835e19f83a25fcffcf3b9fa79cd0c1f15842dc80e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "41c89326b0511a0cc589f59835e19f83a25fcffcf3b9fa79cd0c1f15842dc80e", kill_on_drop: false }`
[INFO] [stdout] 41c89326b0511a0cc589f59835e19f83a25fcffcf3b9fa79cd0c1f15842dc80e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+f6e2f78768c57172b99c3e85892f867894dc7e30" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 499233125dba25b033104362746a3da3f67857ab3419071e47b5a4cb88b4c6aa
[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" "499233125dba25b033104362746a3da3f67857ab3419071e47b5a4cb88b4c6aa", kill_on_drop: false }`
[INFO] [stderr]     Checking rand_core v0.4.0
[INFO] [stderr]     Checking lazy_static v1.3.0
[INFO] [stderr]    Compiling syn v0.15.29
[INFO] [stderr]     Checking regex-syntax v0.6.5
[INFO] [stderr]     Checking log v0.4.6
[INFO] [stderr]    Compiling proc-macro2 v0.4.27
[INFO] [stderr]     Checking thread_local v0.3.6
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking rand_jitter v0.1.3
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking rand_pcg v0.1.2
[INFO] [stderr]     Checking rand_chacha v0.1.1
[INFO] [stderr]     Checking rand_xorshift v0.1.1
[INFO] [stderr]     Checking rand_hc v0.1.0
[INFO] [stderr]     Checking rand_isaac v0.1.1
[INFO] [stderr]     Checking rand v0.6.5
[INFO] [stderr]    Compiling quote v0.6.11
[INFO] [stderr]     Checking regex v1.1.2
[INFO] [stderr]     Checking env_logger v0.6.1
[INFO] [stderr]     Checking quickcheck v0.8.2
[INFO] [stderr]    Compiling quickcheck_macros v0.8.0
[INFO] [stderr]     Checking rust_99_problem v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]  --> src/main.rs:4:13
[INFO] [stdout]   |
[INFO] [stdout] 4 | #[macro_use(quickcheck)]
[INFO] [stdout]   |             ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/solves/p7.rs:14:24
[INFO] [stdout]    |
[INFO] [stdout] 14 |             Node::Item(x) => vec!(node.clone()),
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `is_item`
[INFO] [stdout]   --> src/common.rs:14:13
[INFO] [stdout]    |
[INFO] [stdout] 14 |         let is_item: bool = g.gen();
[INFO] [stdout]    |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_is_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `flat`
[INFO] [stdout]   --> src/solves/p7.rs:11:8
[INFO] [stdout]    |
[INFO] [stdout] 11 | pub fn flat<T: Clone>(ls: &List<T>) -> List<T> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/solves/p7.rs:14:24
[INFO] [stdout]    |
[INFO] [stdout] 14 |             Node::Item(x) => vec!(node.clone()),
[INFO] [stdout]    |                        ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `is_item`
[INFO] [stdout]   --> src/common.rs:14:13
[INFO] [stdout]    |
[INFO] [stdout] 14 |         let is_item: bool = g.gen();
[INFO] [stdout]    |             ^^^^^^^ help: if this is intentional, prefix it with an underscore: `_is_item`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 27.35s
[INFO] running `Command { std: "docker" "inspect" "499233125dba25b033104362746a3da3f67857ab3419071e47b5a4cb88b4c6aa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "499233125dba25b033104362746a3da3f67857ab3419071e47b5a4cb88b4c6aa", kill_on_drop: false }`
[INFO] [stdout] 499233125dba25b033104362746a3da3f67857ab3419071e47b5a4cb88b4c6aa