[INFO] cloning repository https://github.com/JesterOrNot/MathLang
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/JesterOrNot/MathLang" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJesterOrNot%2FMathLang", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJesterOrNot%2FMathLang'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7edd069884e3bfa03c8e9ebc96a30af752c60ff6
[INFO] testing JesterOrNot/MathLang against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FJesterOrNot%2FMathLang" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/JesterOrNot/MathLang on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/JesterOrNot/MathLang
[INFO] finished tweaking git repo https://github.com/JesterOrNot/MathLang
[INFO] tweaked toml for git repo https://github.com/JesterOrNot/MathLang written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/JesterOrNot/MathLang already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded ucd-util v0.1.5
[INFO] [stderr]   Downloaded syn v1.0.13
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] fd1eebce7fa81c400c3aedc7c475d9b9c99418d9703a8dbe9d5bd08401a90713
[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" "fd1eebce7fa81c400c3aedc7c475d9b9c99418d9703a8dbe9d5bd08401a90713", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fd1eebce7fa81c400c3aedc7c475d9b9c99418d9703a8dbe9d5bd08401a90713", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fd1eebce7fa81c400c3aedc7c475d9b9c99418d9703a8dbe9d5bd08401a90713", kill_on_drop: false }`
[INFO] [stdout] fd1eebce7fa81c400c3aedc7c475d9b9c99418d9703a8dbe9d5bd08401a90713
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 354a0d643c3d11dd4d4d43ff885ca394cc153fb343414404845c2ecf0a812619
[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" "354a0d643c3d11dd4d4d43ff885ca394cc153fb343414404845c2ecf0a812619", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.13
[INFO] [stderr]    Compiling regex-syntax v0.5.6
[INFO] [stderr]    Compiling aho-corasick v0.6.10
[INFO] [stderr]    Compiling regex v0.2.11
[INFO] [stderr]    Compiling syn-mid v0.4.0
[INFO] [stderr]    Compiling rustversion v1.0.1
[INFO] [stderr]    Compiling proc-macro-error v0.4.4
[INFO] [stderr]    Compiling proc-macro-error-attr v0.4.3
[INFO] [stderr]    Compiling structopt-derive v0.4.0
[INFO] [stderr]    Compiling structopt v0.3.7
[INFO] [stderr]    Compiling mathlang v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/main.rs:93:13
[INFO] [stdout]    |
[INFO] [stdout] 93 |             &line.push_str("   ");
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 93 |             let _ = &line.push_str("   ");
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 19.56s
[INFO] running `Command { std: "docker" "inspect" "354a0d643c3d11dd4d4d43ff885ca394cc153fb343414404845c2ecf0a812619", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "354a0d643c3d11dd4d4d43ff885ca394cc153fb343414404845c2ecf0a812619", kill_on_drop: false }`
[INFO] [stdout] 354a0d643c3d11dd4d4d43ff885ca394cc153fb343414404845c2ecf0a812619
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+beta-2021-09-08" "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] a6fb8914866c12f0a717932446951c20fba901885847d838da0ac0b70fc30c45
[INFO] running `Command { std: "docker" "start" "-a" "a6fb8914866c12f0a717932446951c20fba901885847d838da0ac0b70fc30c45", kill_on_drop: false }`
[INFO] [stderr]    Compiling mathlang v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/main.rs:93:13
[INFO] [stdout]    |
[INFO] [stdout] 93 |             &line.push_str("   ");
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 93 |             let _ = &line.push_str("   ");
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.85s
[INFO] running `Command { std: "docker" "inspect" "a6fb8914866c12f0a717932446951c20fba901885847d838da0ac0b70fc30c45", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a6fb8914866c12f0a717932446951c20fba901885847d838da0ac0b70fc30c45", kill_on_drop: false }`
[INFO] [stdout] a6fb8914866c12f0a717932446951c20fba901885847d838da0ac0b70fc30c45
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+beta-2021-09-08" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] b3830daacd9e4a59f21145c34b1af53a0ee810c2576a4b781ee8cbbf007e8efc
[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" "b3830daacd9e4a59f21145c34b1af53a0ee810c2576a4b781ee8cbbf007e8efc", kill_on_drop: false }`
[INFO] [stderr] warning: unused borrow that must be used
[INFO] [stderr]   --> src/main.rs:93:13
[INFO] [stderr]    |
[INFO] [stderr] 93 |             &line.push_str("   ");
[INFO] [stderr]    |             ^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr] help: use `let _ = ...` to ignore the resulting value
[INFO] [stderr]    |
[INFO] [stderr] 93 |             let _ = &line.push_str("   ");
[INFO] [stderr]    |             +++++++
[INFO] [stderr] 
[INFO] [stderr] warning: `mathlang` (bin "mathlang" test) generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/mathlang-a1e0d3792cefab69)
[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" "b3830daacd9e4a59f21145c34b1af53a0ee810c2576a4b781ee8cbbf007e8efc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b3830daacd9e4a59f21145c34b1af53a0ee810c2576a4b781ee8cbbf007e8efc", kill_on_drop: false }`
[INFO] [stdout] b3830daacd9e4a59f21145c34b1af53a0ee810c2576a4b781ee8cbbf007e8efc