[INFO] cloning repository https://github.com/ravendyg/rust-playground
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ravendyg/rust-playground" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fravendyg%2Frust-playground", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fravendyg%2Frust-playground'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f0fbaf1c751f3fbfd6b05d9779721bfa5fc7f25f
[INFO] testing ravendyg/rust-playground against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fravendyg%2Frust-playground" "/workspace/builds/worker-5/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/ravendyg/rust-playground 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/ravendyg/rust-playground
[INFO] finished tweaking git repo https://github.com/ravendyg/rust-playground
[INFO] tweaked toml for git repo https://github.com/ravendyg/rust-playground written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] crate git repo https://github.com/ravendyg/rust-playground 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] [stdout] 0c15bfdb2256a51cc3644b01cf67d9b6433b5a84d290131fe21019092a1a3483
[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" "0c15bfdb2256a51cc3644b01cf67d9b6433b5a84d290131fe21019092a1a3483", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0c15bfdb2256a51cc3644b01cf67d9b6433b5a84d290131fe21019092a1a3483", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0c15bfdb2256a51cc3644b01cf67d9b6433b5a84d290131fe21019092a1a3483", kill_on_drop: false }`
[INFO] [stdout] 0c15bfdb2256a51cc3644b01cf67d9b6433b5a84d290131fe21019092a1a3483
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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] 5441acf797142b1a894500d08c95fd1a06cc47cedd0266f898e262d352a8af0c
[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" "5441acf797142b1a894500d08c95fd1a06cc47cedd0266f898e262d352a8af0c", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.18
[INFO] [stderr]    Compiling rand v0.3.15
[INFO] [stderr]    Compiling guessing v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:60:7
[INFO] [stdout]    |
[INFO] [stdout] 60 |   let x: Option<i32> = Option::Some(5);
[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: `q`
[INFO] [stdout]   --> src/main.rs:62:7
[INFO] [stdout]    |
[INFO] [stdout] 62 |   let q: Option<f64> = Option::Some(5f64);
[INFO] [stdout]    |       ^ help: if this is intentional, prefix it with an underscore: `_q`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/main.rs:71:7
[INFO] [stdout]    |
[INFO] [stdout] 71 |   let b = 10;
[INFO] [stdout]    |       ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `None`
[INFO] [stdout]   --> src/main.rs:49:3
[INFO] [stdout]    |
[INFO] [stdout] 49 |   None
[INFO] [stdout]    |   ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Result`
[INFO] [stdout]   --> src/main.rs:53:6
[INFO] [stdout]    |
[INFO] [stdout] 53 | enum Result<T, E> {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.39s
[INFO] running `Command { std: "docker" "inspect" "5441acf797142b1a894500d08c95fd1a06cc47cedd0266f898e262d352a8af0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5441acf797142b1a894500d08c95fd1a06cc47cedd0266f898e262d352a8af0c", kill_on_drop: false }`
[INFO] [stdout] 5441acf797142b1a894500d08c95fd1a06cc47cedd0266f898e262d352a8af0c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5d15e4268045ffa54087655533c1ed9775fb3b59cf12cc80b67584fe520a66db
[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" "5d15e4268045ffa54087655533c1ed9775fb3b59cf12cc80b67584fe520a66db", kill_on_drop: false }`
[INFO] [stderr]    Compiling guessing v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/main.rs:60:7
[INFO] [stdout]    |
[INFO] [stdout] 60 |   let x: Option<i32> = Option::Some(5);
[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: `q`
[INFO] [stdout]   --> src/main.rs:62:7
[INFO] [stdout]    |
[INFO] [stdout] 62 |   let q: Option<f64> = Option::Some(5f64);
[INFO] [stdout]    |       ^ help: if this is intentional, prefix it with an underscore: `_q`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/main.rs:71:7
[INFO] [stdout]    |
[INFO] [stdout] 71 |   let b = 10;
[INFO] [stdout]    |       ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `None`
[INFO] [stdout]   --> src/main.rs:49:3
[INFO] [stdout]    |
[INFO] [stdout] 49 |   None
[INFO] [stdout]    |   ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum is never used: `Result`
[INFO] [stdout]   --> src/main.rs:53:6
[INFO] [stdout]    |
[INFO] [stdout] 53 | enum Result<T, E> {
[INFO] [stdout]    |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 5 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.88s
[INFO] running `Command { std: "docker" "inspect" "5d15e4268045ffa54087655533c1ed9775fb3b59cf12cc80b67584fe520a66db", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5d15e4268045ffa54087655533c1ed9775fb3b59cf12cc80b67584fe520a66db", kill_on_drop: false }`
[INFO] [stdout] 5d15e4268045ffa54087655533c1ed9775fb3b59cf12cc80b67584fe520a66db
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] f43741d3f332dc95e3f8d8302576beac0c5a54162a9d0fbacce40c244769c8a6
[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" "f43741d3f332dc95e3f8d8302576beac0c5a54162a9d0fbacce40c244769c8a6", kill_on_drop: false }`
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/main.rs:60:7
[INFO] [stderr]    |
[INFO] [stderr] 60 |   let x: Option<i32> = Option::Some(5);
[INFO] [stderr]    |       ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `q`
[INFO] [stderr]   --> src/main.rs:62:7
[INFO] [stderr]    |
[INFO] [stderr] 62 |   let q: Option<f64> = Option::Some(5f64);
[INFO] [stderr]    |       ^ help: if this is intentional, prefix it with an underscore: `_q`
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `b`
[INFO] [stderr]   --> src/main.rs:71:7
[INFO] [stderr]    |
[INFO] [stderr] 71 |   let b = 10;
[INFO] [stderr]    |       ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stderr] 
[INFO] [stderr] warning: variant is never constructed: `None`
[INFO] [stderr]   --> src/main.rs:49:3
[INFO] [stderr]    |
[INFO] [stderr] 49 |   None
[INFO] [stderr]    |   ^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: enum is never used: `Result`
[INFO] [stderr]   --> src/main.rs:53:6
[INFO] [stderr]    |
[INFO] [stderr] 53 | enum Result<T, E> {
[INFO] [stderr]    |      ^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 5 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/guessing-46ad1a2595d398ba
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "f43741d3f332dc95e3f8d8302576beac0c5a54162a9d0fbacce40c244769c8a6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f43741d3f332dc95e3f8d8302576beac0c5a54162a9d0fbacce40c244769c8a6", kill_on_drop: false }`
[INFO] [stdout] f43741d3f332dc95e3f8d8302576beac0c5a54162a9d0fbacce40c244769c8a6