[INFO] cloning repository https://github.com/kbacha/string-clone-performance-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kbacha/string-clone-performance-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkbacha%2Fstring-clone-performance-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkbacha%2Fstring-clone-performance-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] dbbcf257a78bae12cff841f781eac3a6ae9ccac3
[INFO] testing kbacha/string-clone-performance-rust against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkbacha%2Fstring-clone-performance-rust" "/workspace/builds/worker-4/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kbacha/string-clone-performance-rust 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/kbacha/string-clone-performance-rust
[INFO] finished tweaking git repo https://github.com/kbacha/string-clone-performance-rust
[INFO] tweaked toml for git repo https://github.com/kbacha/string-clone-performance-rust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/kbacha/string-clone-performance-rust 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-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] [stdout] 6a53443ce4ba1786b9f0f476eb575b833203712f9c277447ece7ab45e31ab368
[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" "6a53443ce4ba1786b9f0f476eb575b833203712f9c277447ece7ab45e31ab368", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6a53443ce4ba1786b9f0f476eb575b833203712f9c277447ece7ab45e31ab368", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6a53443ce4ba1786b9f0f476eb575b833203712f9c277447ece7ab45e31ab368", kill_on_drop: false }`
[INFO] [stdout] 6a53443ce4ba1786b9f0f476eb575b833203712f9c277447ece7ab45e31ab368
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 896e3f5583ef8b924ede8d9d329be1fcfc025e4f0d05ca343e866b04cc683f91
[INFO] running `Command { std: "docker" "start" "-a" "896e3f5583ef8b924ede8d9d329be1fcfc025e4f0d05ca343e866b04cc683f91", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling string-clone-performance v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:13:38
[INFO] [stdout]    |
[INFO] [stdout] 13 |     time("100 rs", 100_000_000, || { s.clone(); });
[INFO] [stdout]    |                                      ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:15:39
[INFO] [stdout]    |
[INFO] [stdout] 15 |     time("1000 rs", 100_000_000, || { s.clone(); });
[INFO] [stdout]    |                                       ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:17:41
[INFO] [stdout]    |
[INFO] [stdout] 17 |     time("10,000 rs", 100_000_000, || { s.clone(); });
[INFO] [stdout]    |                                         ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:19:41
[INFO] [stdout]    |
[INFO] [stdout] 19 |     time("100,000 rs", 10_000_000, || { s.clone(); });
[INFO] [stdout]    |                                         ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.77s
[INFO] running `Command { std: "docker" "inspect" "896e3f5583ef8b924ede8d9d329be1fcfc025e4f0d05ca343e866b04cc683f91", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "896e3f5583ef8b924ede8d9d329be1fcfc025e4f0d05ca343e866b04cc683f91", kill_on_drop: false }`
[INFO] [stdout] 896e3f5583ef8b924ede8d9d329be1fcfc025e4f0d05ca343e866b04cc683f91
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 2ce225ecadf86a718f82d21163f3450c05be76409dee1e17138a749f2d24e21f
[INFO] running `Command { std: "docker" "start" "-a" "2ce225ecadf86a718f82d21163f3450c05be76409dee1e17138a749f2d24e21f", kill_on_drop: false }`
[INFO] [stderr]    Compiling string-clone-performance v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:13:38
[INFO] [stdout]    |
[INFO] [stdout] 13 |     time("100 rs", 100_000_000, || { s.clone(); });
[INFO] [stdout]    |                                      ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:15:39
[INFO] [stdout]    |
[INFO] [stdout] 15 |     time("1000 rs", 100_000_000, || { s.clone(); });
[INFO] [stdout]    |                                       ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:17:41
[INFO] [stdout]    |
[INFO] [stdout] 17 |     time("10,000 rs", 100_000_000, || { s.clone(); });
[INFO] [stdout]    |                                         ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `clone` that must be used
[INFO] [stdout]   --> src/main.rs:19:41
[INFO] [stdout]    |
[INFO] [stdout] 19 |     time("100,000 rs", 10_000_000, || { s.clone(); });
[INFO] [stdout]    |                                         ^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.81s
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "2ce225ecadf86a718f82d21163f3450c05be76409dee1e17138a749f2d24e21f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2ce225ecadf86a718f82d21163f3450c05be76409dee1e17138a749f2d24e21f", kill_on_drop: false }`
[INFO] [stdout] 2ce225ecadf86a718f82d21163f3450c05be76409dee1e17138a749f2d24e21f
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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] 469e6224b3634f480fac9a3ea66699c9154b2c1894d446aecdcd11ad8f173b7e
[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" "469e6224b3634f480fac9a3ea66699c9154b2c1894d446aecdcd11ad8f173b7e", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr] warning: unused return value of `clone` that must be used
[INFO] [stdout] running 0 tests
[INFO] [stderr]   --> src/main.rs:13:38
[INFO] [stdout] 
[INFO] [stderr]    |
[INFO] [stdout] test result: ok. 0 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stderr] 13 |     time("100 rs", 100_000_000, || { s.clone(); });
[INFO] [stdout] 
[INFO] [stderr]    |                                      ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `clone` that must be used
[INFO] [stderr]   --> src/main.rs:15:39
[INFO] [stderr]    |
[INFO] [stderr] 15 |     time("1000 rs", 100_000_000, || { s.clone(); });
[INFO] [stderr]    |                                       ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `clone` that must be used
[INFO] [stderr]   --> src/main.rs:17:41
[INFO] [stderr]    |
[INFO] [stderr] 17 |     time("10,000 rs", 100_000_000, || { s.clone(); });
[INFO] [stderr]    |                                         ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stderr] 
[INFO] [stderr] warning: unused return value of `clone` that must be used
[INFO] [stderr]   --> src/main.rs:19:41
[INFO] [stderr]    |
[INFO] [stderr] 19 |     time("100,000 rs", 10_000_000, || { s.clone(); });
[INFO] [stderr]    |                                         ^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: cloning is often expensive and is not expected to have side effects
[INFO] [stderr] 
[INFO] [stderr] warning: `string-clone-performance` (bin "string-clone-performance" test) generated 4 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/string_clone_performance-48b8bea891b0f9a8)
[INFO] running `Command { std: "docker" "inspect" "469e6224b3634f480fac9a3ea66699c9154b2c1894d446aecdcd11ad8f173b7e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "469e6224b3634f480fac9a3ea66699c9154b2c1894d446aecdcd11ad8f173b7e", kill_on_drop: false }`
[INFO] [stdout] 469e6224b3634f480fac9a3ea66699c9154b2c1894d446aecdcd11ad8f173b7e