[INFO] cloning repository https://github.com/p-flock/matmult-rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/p-flock/matmult-rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fp-flock%2Fmatmult-rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fp-flock%2Fmatmult-rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 868f3c9e49d4c7572f9160733a9f6e51095590e0
[INFO] testing p-flock/matmult-rust 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%2Fp-flock%2Fmatmult-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/p-flock/matmult-rust 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/p-flock/matmult-rust
[INFO] finished tweaking git repo https://github.com/p-flock/matmult-rust
[INFO] tweaked toml for git repo https://github.com/p-flock/matmult-rust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/p-flock/matmult-rust 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] 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" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 570febe8692b9bfdf69f4176733f5f8e88720f7fba6d7d980c465005f1caee88
[INFO] running `Command { std: "docker" "start" "-a" "570febe8692b9bfdf69f4176733f5f8e88720f7fba6d7d980c465005f1caee88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "570febe8692b9bfdf69f4176733f5f8e88720f7fba6d7d980c465005f1caee88", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "570febe8692b9bfdf69f4176733f5f8e88720f7fba6d7d980c465005f1caee88", kill_on_drop: false }`
[INFO] [stdout] 570febe8692b9bfdf69f4176733f5f8e88720f7fba6d7d980c465005f1caee88
[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" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 30e06f508a52e8090f7ec776f55a03d3094bce1cc837759169c79c83b55c0abc
[INFO] running `Command { std: "docker" "start" "-a" "30e06f508a52e8090f7ec776f55a03d3094bce1cc837759169c79c83b55c0abc", kill_on_drop: false }`
[INFO] [stderr]    Compiling multi_matmult v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/main.rs:31:34
[INFO] [stdout]    |
[INFO] [stdout] 31 | fn parse_matrix(file_1: &str) -> (Vec<Vec<f64>>) {
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `output_matrix`
[INFO] [stdout]   --> src/main.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let output_matrix = multiply_matrices(&a, &b);
[INFO] [stdout]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_output_matrix`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.02s
[INFO] running `Command { std: "docker" "inspect" "30e06f508a52e8090f7ec776f55a03d3094bce1cc837759169c79c83b55c0abc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "30e06f508a52e8090f7ec776f55a03d3094bce1cc837759169c79c83b55c0abc", kill_on_drop: false }`
[INFO] [stdout] 30e06f508a52e8090f7ec776f55a03d3094bce1cc837759169c79c83b55c0abc
[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" "+beta-2021-09-08" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4d1031a0c602bab21c24e3ff0b6705fd4d9940cc54ed3d84406c992824de39b3
[INFO] running `Command { std: "docker" "start" "-a" "4d1031a0c602bab21c24e3ff0b6705fd4d9940cc54ed3d84406c992824de39b3", kill_on_drop: false }`
[INFO] [stderr]    Compiling multi_matmult v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around type
[INFO] [stdout]   --> src/main.rs:31:34
[INFO] [stdout]    |
[INFO] [stdout] 31 | fn parse_matrix(file_1: &str) -> (Vec<Vec<f64>>) {
[INFO] [stdout]    |                                  ^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `output_matrix`
[INFO] [stdout]   --> src/main.rs:16:9
[INFO] [stdout]    |
[INFO] [stdout] 16 |     let output_matrix = multiply_matrices(&a, &b);
[INFO] [stdout]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_output_matrix`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.72s
[INFO] running `Command { std: "docker" "inspect" "4d1031a0c602bab21c24e3ff0b6705fd4d9940cc54ed3d84406c992824de39b3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d1031a0c602bab21c24e3ff0b6705fd4d9940cc54ed3d84406c992824de39b3", kill_on_drop: false }`
[INFO] [stdout] 4d1031a0c602bab21c24e3ff0b6705fd4d9940cc54ed3d84406c992824de39b3
[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" "+beta-2021-09-08" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 3a32bf03f7e183cd3a223e0c3b141c726bd20b48821cd688eaf6bdeccc04b46e
[INFO] running `Command { std: "docker" "start" "-a" "3a32bf03f7e183cd3a223e0c3b141c726bd20b48821cd688eaf6bdeccc04b46e", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stderr] warning: unnecessary parentheses around type
[INFO] [stdout] running 0 tests
[INFO] [stderr]   --> src/main.rs:31:34
[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] 31 | fn parse_matrix(file_1: &str) -> (Vec<Vec<f64>>) {
[INFO] [stdout] 
[INFO] [stderr]    |                                  ^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `output_matrix`
[INFO] [stderr]   --> src/main.rs:16:9
[INFO] [stderr]    |
[INFO] [stderr] 16 |     let output_matrix = multiply_matrices(&a, &b);
[INFO] [stderr]    |         ^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_output_matrix`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: `multi_matmult` (bin "multi_matmult" test) generated 2 warnings
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/multi_matmult-f8c0b5beffc76031)
[INFO] running `Command { std: "docker" "inspect" "3a32bf03f7e183cd3a223e0c3b141c726bd20b48821cd688eaf6bdeccc04b46e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3a32bf03f7e183cd3a223e0c3b141c726bd20b48821cd688eaf6bdeccc04b46e", kill_on_drop: false }`
[INFO] [stdout] 3a32bf03f7e183cd3a223e0c3b141c726bd20b48821cd688eaf6bdeccc04b46e