[INFO] cloning repository https://github.com/friendbear/stepByStepRust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/friendbear/stepByStepRust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffriendbear%2FstepByStepRust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffriendbear%2FstepByStepRust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] dc045f3e4c69e97a6eda85d500c59c754c76c844
[INFO] testing friendbear/stepByStepRust against beta-2021-01-01 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ffriendbear%2FstepByStepRust" "/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/friendbear/stepByStepRust on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/friendbear/stepByStepRust
[INFO] finished tweaking git repo https://github.com/friendbear/stepByStepRust
[INFO] tweaked toml for git repo https://github.com/friendbear/stepByStepRust written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] crate git repo https://github.com/friendbear/stepByStepRust already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "fetch" "--locked" "--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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "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] 093d0d83e48edf5665405492cccfab633588b96dc9732083f8b4e1a6fbbcfba0
[INFO] running `Command { std: "docker" "start" "-a" "093d0d83e48edf5665405492cccfab633588b96dc9732083f8b4e1a6fbbcfba0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "093d0d83e48edf5665405492cccfab633588b96dc9732083f8b4e1a6fbbcfba0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "093d0d83e48edf5665405492cccfab633588b96dc9732083f8b4e1a6fbbcfba0", kill_on_drop: false }`
[INFO] [stdout] 093d0d83e48edf5665405492cccfab633588b96dc9732083f8b4e1a6fbbcfba0
[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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 35bf7804b05c7ce8db7a717c523e87cc490088d87d9a9760929134b3792908c8
[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" "35bf7804b05c7ce8db7a717c523e87cc490088d87d9a9760929134b3792908c8", kill_on_drop: false }`
[INFO] [stderr]    Compiling hello_world v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function is never used: `main_dummy`
[INFO] [stdout]  --> src/main.rs:4:4
[INFO] [stdout]   |
[INFO] [stdout] 4 | fn main_dummy() {
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `language`
[INFO] [stdout]  --> src/main.rs:8:4
[INFO] [stdout]   |
[INFO] [stdout] 8 | fn language() -> String {
[INFO] [stdout]   |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 49 |         writeln!(std::io::stderr(), "Usage; gcd NUMBER ...");
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.99s
[INFO] running `Command { std: "docker" "inspect" "35bf7804b05c7ce8db7a717c523e87cc490088d87d9a9760929134b3792908c8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "35bf7804b05c7ce8db7a717c523e87cc490088d87d9a9760929134b3792908c8", kill_on_drop: false }`
[INFO] [stdout] 35bf7804b05c7ce8db7a717c523e87cc490088d87d9a9760929134b3792908c8
[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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "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] 737b20acaf7fa584dc55108b907b7f8553a563eed59835caa1ac956ba26c67b7
[INFO] running `Command { std: "docker" "start" "-a" "737b20acaf7fa584dc55108b907b7f8553a563eed59835caa1ac956ba26c67b7", kill_on_drop: false }`
[INFO] [stderr]    Compiling hello_world v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: function is never used: `main_dummy`
[INFO] [stdout]  --> src/main.rs:4:4
[INFO] [stdout]   |
[INFO] [stdout] 4 | fn main_dummy() {
[INFO] [stdout]   |    ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `std::result::Result` that must be used
[INFO] [stdout]   --> src/main.rs:49:9
[INFO] [stdout]    |
[INFO] [stdout] 49 |         writeln!(std::io::stderr(), "Usage; gcd NUMBER ...");
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.01s
[INFO] running `Command { std: "docker" "inspect" "737b20acaf7fa584dc55108b907b7f8553a563eed59835caa1ac956ba26c67b7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "737b20acaf7fa584dc55108b907b7f8553a563eed59835caa1ac956ba26c67b7", kill_on_drop: false }`
[INFO] [stdout] 737b20acaf7fa584dc55108b907b7f8553a563eed59835caa1ac956ba26c67b7
[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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] 21751e5d196f8138c85e7e6cc14bec71be7f5ca3f22448be5825b323a046ea27
[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" "21751e5d196f8138c85e7e6cc14bec71be7f5ca3f22448be5825b323a046ea27", kill_on_drop: false }`
[INFO] [stdout] 
[INFO] [stdout] running 2 tests
[INFO] [stdout] test test_gcd ... ok
[INFO] [stdout] test test_language ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 2 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr] warning: function is never used: `main_dummy`
[INFO] [stderr]  --> src/main.rs:4:4
[INFO] [stderr]   |
[INFO] [stderr] 4 | fn main_dummy() {
[INFO] [stderr]   |    ^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(dead_code)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused `std::result::Result` that must be used
[INFO] [stderr]   --> src/main.rs:49:9
[INFO] [stderr]    |
[INFO] [stderr] 49 |         writeln!(std::io::stderr(), "Usage; gcd NUMBER ...");
[INFO] [stderr]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stderr]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stderr]    = note: this warning originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stderr] 
[INFO] [stderr] warning: 2 warnings emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/hello_world-e7c042202f3b4d5e
[INFO] running `Command { std: "docker" "inspect" "21751e5d196f8138c85e7e6cc14bec71be7f5ca3f22448be5825b323a046ea27", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21751e5d196f8138c85e7e6cc14bec71be7f5ca3f22448be5825b323a046ea27", kill_on_drop: false }`
[INFO] [stdout] 21751e5d196f8138c85e7e6cc14bec71be7f5ca3f22448be5825b323a046ea27