[INFO] updating cached repository d-silvas/intro-to-rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/d-silvas/intro-to-rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/d-silvas/intro-to-rust" "work/ex/beta-1.38-1/sources/1.37.0/gh/d-silvas/intro-to-rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/d-silvas/intro-to-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/d-silvas/intro-to-rust" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/d-silvas/intro-to-rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/d-silvas/intro-to-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] c3bfa0461d1eb0474a22312c85e57430c1839c5e
[INFO] sha for GitHub repo d-silvas/intro-to-rust: c3bfa0461d1eb0474a22312c85e57430c1839c5e
[INFO] validating manifest of d-silvas/intro-to-rust on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of d-silvas/intro-to-rust on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing d-silvas/intro-to-rust
[INFO] finished frobbing d-silvas/intro-to-rust
[INFO] frobbed toml for d-silvas/intro-to-rust written to work/ex/beta-1.38-1/sources/1.37.0/gh/d-silvas/intro-to-rust/Cargo.toml
[INFO] started frobbing d-silvas/intro-to-rust
[INFO] finished frobbing d-silvas/intro-to-rust
[INFO] frobbed toml for d-silvas/intro-to-rust written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/d-silvas/intro-to-rust/Cargo.toml
[INFO] crate d-silvas/intro-to-rust already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing d-silvas/intro-to-rust against 1.37.0 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/d-silvas/intro-to-rust:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "build" "--frozen"`
[INFO] [stdout] 419f6f8e1e4307c0a73557ba59db18324e2725dcafd60bf5108c77e1c581bbba
[INFO] running `"docker" "start" "-a" "419f6f8e1e4307c0a73557ba59db18324e2725dcafd60bf5108c77e1c581bbba"`
[INFO] [stderr]    Compiling num-bigint v0.2.2
[INFO] [stderr]    Compiling intro-to-rust v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]  --> src/main.rs:7:7
[INFO] [stderr]   |
[INFO] [stderr] 7 |   let x = 1;
[INFO] [stderr]   |       ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `z`
[INFO] [stderr]   --> src/main.rs:27:7
[INFO] [stderr]    |
[INFO] [stderr] 27 |   let z = &y;
[INFO] [stderr]    |       ^ help: consider prefixing with an underscore: `_z`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.30s
[INFO] running `"docker" "inspect" "419f6f8e1e4307c0a73557ba59db18324e2725dcafd60bf5108c77e1c581bbba"`
[INFO] running `"docker" "rm" "-f" "419f6f8e1e4307c0a73557ba59db18324e2725dcafd60bf5108c77e1c581bbba"`
[INFO] [stdout] 419f6f8e1e4307c0a73557ba59db18324e2725dcafd60bf5108c77e1c581bbba
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/d-silvas/intro-to-rust:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] e06e283a1e24fbf8c92ec7fe9e67aff744445bda5a429382f5801d5be6bc6c8e
[INFO] running `"docker" "start" "-a" "e06e283a1e24fbf8c92ec7fe9e67aff744445bda5a429382f5801d5be6bc6c8e"`
[INFO] [stderr]    Compiling intro-to-rust v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]  --> src/main.rs:7:7
[INFO] [stderr]   |
[INFO] [stderr] 7 |   let x = 1;
[INFO] [stderr]   |       ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_variables)] on by default
[INFO] [stderr] 
[INFO] [stderr] warning: unused variable: `z`
[INFO] [stderr]   --> src/main.rs:27:7
[INFO] [stderr]    |
[INFO] [stderr] 27 |   let z = &y;
[INFO] [stderr]    |       ^ help: consider prefixing with an underscore: `_z`
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.68s
[INFO] running `"docker" "inspect" "e06e283a1e24fbf8c92ec7fe9e67aff744445bda5a429382f5801d5be6bc6c8e"`
[INFO] running `"docker" "rm" "-f" "e06e283a1e24fbf8c92ec7fe9e67aff744445bda5a429382f5801d5be6bc6c8e"`
[INFO] [stdout] e06e283a1e24fbf8c92ec7fe9e67aff744445bda5a429382f5801d5be6bc6c8e
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-6/1.37.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/1.37.0/gh/d-silvas/intro-to-rust:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+1.37.0" "test" "--frozen"`
[INFO] [stdout] ac8fe63709644d6ac84775c01e9e6cb584e4a513283d6345ce4ab7c8c60471d0
[INFO] running `"docker" "start" "-a" "ac8fe63709644d6ac84775c01e9e6cb584e4a513283d6345ce4ab7c8c60471d0"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.02s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/intro_to_rust-819352c928e5cdd6
[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
[INFO] [stdout] 
[INFO] running `"docker" "inspect" "ac8fe63709644d6ac84775c01e9e6cb584e4a513283d6345ce4ab7c8c60471d0"`
[INFO] running `"docker" "rm" "-f" "ac8fe63709644d6ac84775c01e9e6cb584e4a513283d6345ce4ab7c8c60471d0"`
[INFO] [stdout] ac8fe63709644d6ac84775c01e9e6cb584e4a513283d6345ce4ab7c8c60471d0