[INFO] fetching crate head_tail 0.1.0...
[INFO] testing head_tail-0.1.0 against try#b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b for pr-145330-1
[INFO] extracting crate head_tail 0.1.0 into /workspace/builds/worker-4-tc2/source
[INFO] removed /workspace/builds/worker-4-tc2/source/rust-toolchain.toml
[INFO] started tweaking crates.io crate head_tail 0.1.0
[INFO] finished tweaking crates.io crate head_tail 0.1.0
[INFO] tweaked toml for crates.io crate head_tail 0.1.0 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate head_tail 0.1.0 on toolchain b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate head_tail 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bbb10c50732b0be55e5d323eff658ee5873e93a78e3a48b3f23ad78e9a04f50d
[INFO] running `Command { std: "docker" "start" "-a" "bbb10c50732b0be55e5d323eff658ee5873e93a78e3a48b3f23ad78e9a04f50d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bbb10c50732b0be55e5d323eff658ee5873e93a78e3a48b3f23ad78e9a04f50d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bbb10c50732b0be55e5d323eff658ee5873e93a78e3a48b3f23ad78e9a04f50d", kill_on_drop: false }`
[INFO] [stdout] bbb10c50732b0be55e5d323eff658ee5873e93a78e3a48b3f23ad78e9a04f50d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a599c24b18bd3cc88b4ac5a591acc23eae0a8b2c5b1a44c7ced1fd2967293115
[INFO] running `Command { std: "docker" "start" "-a" "a599c24b18bd3cc88b4ac5a591acc23eae0a8b2c5b1a44c7ced1fd2967293115", kill_on_drop: false }`
[INFO] [stderr]    Compiling head_tail v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/head_tail.rs:18:10
[INFO] [stdout]    |
[INFO] [stdout] 18 |     for (i, line) in reader.lines().enumerate().take(n) {
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.85s
[INFO] running `Command { std: "docker" "inspect" "a599c24b18bd3cc88b4ac5a591acc23eae0a8b2c5b1a44c7ced1fd2967293115", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a599c24b18bd3cc88b4ac5a591acc23eae0a8b2c5b1a44c7ced1fd2967293115", kill_on_drop: false }`
[INFO] [stdout] a599c24b18bd3cc88b4ac5a591acc23eae0a8b2c5b1a44c7ced1fd2967293115
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2513db7a2bb50678e814116ea0e7dd3ddf939c4f313426ca3e4ed92f13151113
[INFO] running `Command { std: "docker" "start" "-a" "2513db7a2bb50678e814116ea0e7dd3ddf939c4f313426ca3e4ed92f13151113", kill_on_drop: false }`
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/head_tail.rs:18:10
[INFO] [stdout]    |
[INFO] [stdout] 18 |     for (i, line) in reader.lines().enumerate().take(n) {
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling head_tail v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/head_tail.rs:18:10
[INFO] [stdout]    |
[INFO] [stdout] 18 |     for (i, line) in reader.lines().enumerate().take(n) {
[INFO] [stdout]    |          ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.46s
[INFO] running `Command { std: "docker" "inspect" "2513db7a2bb50678e814116ea0e7dd3ddf939c4f313426ca3e4ed92f13151113", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2513db7a2bb50678e814116ea0e7dd3ddf939c4f313426ca3e4ed92f13151113", kill_on_drop: false }`
[INFO] [stdout] 2513db7a2bb50678e814116ea0e7dd3ddf939c4f313426ca3e4ed92f13151113
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/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" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+b6ae10aa7319b7ebb6c7b3331dd71a9d6c9c5b4b" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 31225734e92877dfd649d5ac4f2bf7faf01892dad9930e421790821c242164c9
[INFO] running `Command { std: "docker" "start" "-a" "31225734e92877dfd649d5ac4f2bf7faf01892dad9930e421790821c242164c9", kill_on_drop: false }`
[INFO] [stderr] warning: unused variable: `i`
[INFO] [stdout] 
[INFO] [stderr]   --> src/head_tail.rs:18:10
[INFO] [stdout] running 0 tests
[INFO] [stderr]    |
[INFO] [stdout] 
[INFO] [stderr] 18 |     for (i, line) in reader.lines().enumerate().take(n) {
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr]    |          ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout] 
[INFO] [stderr]    |
[INFO] [stdout] 
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] running 1 test
[INFO] [stderr] 
[INFO] [stderr] warning: `head_tail` (lib) generated 1 warning
[INFO] [stderr] warning: `head_tail` (lib test) generated 1 warning (1 duplicate)
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running unittests src/head_tail.rs (/opt/rustwide/target/debug/deps/head_tail-98d9014d3dd2852f)
[INFO] [stderr]      Running unittests src/main.rs (/opt/rustwide/target/debug/deps/head_tail-ae1cbc6036f4eb10)
[INFO] [stdout] test tests::test_math ... ok
[INFO] [stderr]    Doc-tests head_tail
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] running 0 tests
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "31225734e92877dfd649d5ac4f2bf7faf01892dad9930e421790821c242164c9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31225734e92877dfd649d5ac4f2bf7faf01892dad9930e421790821c242164c9", kill_on_drop: false }`
[INFO] [stdout] 31225734e92877dfd649d5ac4f2bf7faf01892dad9930e421790821c242164c9