[INFO] fetching crate develop_debug 0.1.2...
[INFO] checking develop_debug-0.1.2 against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] extracting crate develop_debug 0.1.2 into /workspace/builds/worker-10/source
[INFO] validating manifest of crates.io crate develop_debug 0.1.2 on toolchain 45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate develop_debug 0.1.2
[INFO] finished tweaking crates.io crate develop_debug 0.1.2
[INFO] tweaked toml for crates.io crate develop_debug 0.1.2 written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 15a2c60b5f227c8f5e930b3809c03cc4df2d75859890a2c35a37202a44c71ba6
[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" "15a2c60b5f227c8f5e930b3809c03cc4df2d75859890a2c35a37202a44c71ba6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "15a2c60b5f227c8f5e930b3809c03cc4df2d75859890a2c35a37202a44c71ba6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "15a2c60b5f227c8f5e930b3809c03cc4df2d75859890a2c35a37202a44c71ba6", kill_on_drop: false }`
[INFO] [stdout] 15a2c60b5f227c8f5e930b3809c03cc4df2d75859890a2c35a37202a44c71ba6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4537364bad3cfc286bbc3f6c56a92e411ced3d98f7e638a9c6a1a6fad1639d4e
[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" "4537364bad3cfc286bbc3f6c56a92e411ced3d98f7e638a9c6a1a6fad1639d4e", kill_on_drop: false }`
[INFO] [stderr]     Checking develop_debug v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]  --> tests/how_to_use.rs:5:9
[INFO] [stdout]   |
[INFO] [stdout] 5 |     let x = "dear X";
[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: `say`
[INFO] [stdout]  --> tests/how_to_use.rs:6:9
[INFO] [stdout]   |
[INFO] [stdout] 6 |     let say = "hello world!";
[INFO] [stdout]   |         ^^^ help: if this is intentional, prefix it with an underscore: `_say`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `array`
[INFO] [stdout]  --> tests/how_to_use.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 |     let array = vec!["a", "b", "c"];
[INFO] [stdout]   |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_array`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `title2`
[INFO] [stdout]  --> tests/how_to_use.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     let title2 = "balabala...";
[INFO] [stdout]   |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_title2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> tests/how_to_use.rs:23:9
[INFO] [stdout]    |
[INFO] [stdout] 23 |     let x = "dear X";
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `say`
[INFO] [stdout]   --> tests/how_to_use.rs:24:9
[INFO] [stdout]    |
[INFO] [stdout] 24 |     let say = "hello world!";
[INFO] [stdout]    |         ^^^ help: if this is intentional, prefix it with an underscore: `_say`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `array`
[INFO] [stdout]   --> tests/how_to_use.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |     let array = vec!["a", "b", "c"];
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_array`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `title2`
[INFO] [stdout]   --> tests/how_to_use.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let title2 = "balabala...";
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_title2`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.63s
[INFO] running `Command { std: "docker" "inspect" "4537364bad3cfc286bbc3f6c56a92e411ced3d98f7e638a9c6a1a6fad1639d4e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4537364bad3cfc286bbc3f6c56a92e411ced3d98f7e638a9c6a1a6fad1639d4e", kill_on_drop: false }`
[INFO] [stdout] 4537364bad3cfc286bbc3f6c56a92e411ced3d98f7e638a9c6a1a6fad1639d4e