[INFO] cloning repository https://github.com/zhangshuyx/dangling_references
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/zhangshuyx/dangling_references" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangshuyx%2Fdangling_references", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangshuyx%2Fdangling_references'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cdbcb7b85a6a90a695b126b504def976d60c726a
[INFO] testing zhangshuyx/dangling_references against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzhangshuyx%2Fdangling_references" "/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/zhangshuyx/dangling_references on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/zhangshuyx/dangling_references
[INFO] finished tweaking git repo https://github.com/zhangshuyx/dangling_references
[INFO] tweaked toml for git repo https://github.com/zhangshuyx/dangling_references written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/zhangshuyx/dangling_references already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] d558e7c63317e34411bb625ee299beb303c807f8934ec34542ea1609b3dbbd12
[INFO] running `Command { std: "docker" "start" "-a" "d558e7c63317e34411bb625ee299beb303c807f8934ec34542ea1609b3dbbd12", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d558e7c63317e34411bb625ee299beb303c807f8934ec34542ea1609b3dbbd12", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d558e7c63317e34411bb625ee299beb303c807f8934ec34542ea1609b3dbbd12", kill_on_drop: false }`
[INFO] [stdout] d558e7c63317e34411bb625ee299beb303c807f8934ec34542ea1609b3dbbd12
[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=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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 82e665557ee6111d0bd2db6a7f3c6954cb81c00bf664b245e9e648e006bbd476
[INFO] running `Command { std: "docker" "start" "-a" "82e665557ee6111d0bd2db6a7f3c6954cb81c00bf664b245e9e648e006bbd476", kill_on_drop: false }`
[INFO] [stderr]    Compiling dangling_references v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `string`
[INFO] [stdout]  --> src/main.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let string = no_dangle();
[INFO] [stdout]   |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_string`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.47s
[INFO] running `Command { std: "docker" "inspect" "82e665557ee6111d0bd2db6a7f3c6954cb81c00bf664b245e9e648e006bbd476", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "82e665557ee6111d0bd2db6a7f3c6954cb81c00bf664b245e9e648e006bbd476", kill_on_drop: false }`
[INFO] [stdout] 82e665557ee6111d0bd2db6a7f3c6954cb81c00bf664b245e9e648e006bbd476
[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=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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 832a3ab6e454f153b562259befe42ca2db8295676800441a08dd83f8693c26e4
[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" "832a3ab6e454f153b562259befe42ca2db8295676800441a08dd83f8693c26e4", kill_on_drop: false }`
[INFO] [stderr]    Compiling dangling_references v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `string`
[INFO] [stdout]  --> src/main.rs:3:9
[INFO] [stdout]   |
[INFO] [stdout] 3 |     let string = no_dangle();
[INFO] [stdout]   |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_string`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.40s
[INFO] running `Command { std: "docker" "inspect" "832a3ab6e454f153b562259befe42ca2db8295676800441a08dd83f8693c26e4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "832a3ab6e454f153b562259befe42ca2db8295676800441a08dd83f8693c26e4", kill_on_drop: false }`
[INFO] [stdout] 832a3ab6e454f153b562259befe42ca2db8295676800441a08dd83f8693c26e4
[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=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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 4ac413adccb955802c879b3c25314bed7de7c4eb1e780dd8a7a7d7c84410032e
[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" "4ac413adccb955802c879b3c25314bed7de7c4eb1e780dd8a7a7d7c84410032e", kill_on_drop: false }`
[INFO] [stderr] warning: unused variable: `string`
[INFO] [stderr]  --> src/main.rs:3:9
[INFO] [stderr]   |
[INFO] [stderr] 3 |     let string = no_dangle();
[INFO] [stderr]   |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_string`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `dangling_references` (bin "dangling_references" test) generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.00s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/dangling_references-34d745e11aaeda1d)
[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" "4ac413adccb955802c879b3c25314bed7de7c4eb1e780dd8a7a7d7c84410032e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4ac413adccb955802c879b3c25314bed7de7c4eb1e780dd8a7a7d7c84410032e", kill_on_drop: false }`
[INFO] [stdout] 4ac413adccb955802c879b3c25314bed7de7c4eb1e780dd8a7a7d7c84410032e