[INFO] updating cached repository ajames72/rust-basics
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/ajames72/rust-basics
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/ajames72/rust-basics" "work/ex/beta-1.38-1/sources/1.37.0/gh/ajames72/rust-basics"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/ajames72/rust-basics'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/ajames72/rust-basics" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ajames72/rust-basics"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ajames72/rust-basics'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 2628779b41d77c2c35a75e1ab3bce18f3631779c
[INFO] sha for GitHub repo ajames72/rust-basics: 2628779b41d77c2c35a75e1ab3bce18f3631779c
[INFO] validating manifest of ajames72/rust-basics 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 ajames72/rust-basics 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 ajames72/rust-basics
[INFO] finished frobbing ajames72/rust-basics
[INFO] frobbed toml for ajames72/rust-basics written to work/ex/beta-1.38-1/sources/1.37.0/gh/ajames72/rust-basics/Cargo.toml
[INFO] started frobbing ajames72/rust-basics
[INFO] finished frobbing ajames72/rust-basics
[INFO] frobbed toml for ajames72/rust-basics written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ajames72/rust-basics/Cargo.toml
[INFO] crate ajames72/rust-basics 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 ajames72/rust-basics against beta-2019-08-13 for beta-1.38-1
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ajames72/rust-basics:/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" "+beta-2019-08-13" "build" "--frozen"`
[INFO] [stdout] 06ae648edfe5cc0d266bdf45061f3191c4b8870b715bc880387d4d52883c53fc
[INFO] running `"docker" "start" "-a" "06ae648edfe5cc0d266bdf45061f3191c4b8870b715bc880387d4d52883c53fc"`
[INFO] [stderr]    Compiling rust-basics v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/basics.rs:62:13
[INFO] [stderr]    |
[INFO] [stderr] 62 |         let x = 7; // generates a warning 'help: consider using `_x` instead'
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.94s
[INFO] running `"docker" "inspect" "06ae648edfe5cc0d266bdf45061f3191c4b8870b715bc880387d4d52883c53fc"`
[INFO] running `"docker" "rm" "-f" "06ae648edfe5cc0d266bdf45061f3191c4b8870b715bc880387d4d52883c53fc"`
[INFO] [stdout] 06ae648edfe5cc0d266bdf45061f3191c4b8870b715bc880387d4d52883c53fc
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ajames72/rust-basics:/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" "+beta-2019-08-13" "test" "--frozen" "--no-run"`
[INFO] [stdout] e703b9f4fb5d3d62252a125672813cd11b57282e18db629669987dbafb174a03
[INFO] running `"docker" "start" "-a" "e703b9f4fb5d3d62252a125672813cd11b57282e18db629669987dbafb174a03"`
[INFO] [stderr]    Compiling rust-basics v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused variable: `x`
[INFO] [stderr]   --> src/basics.rs:62:13
[INFO] [stderr]    |
[INFO] [stderr] 62 |         let x = 7; // generates a warning 'help: consider using `_x` instead'
[INFO] [stderr]    |             ^ help: consider prefixing with an underscore: `_x`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.67s
[INFO] running `"docker" "inspect" "e703b9f4fb5d3d62252a125672813cd11b57282e18db629669987dbafb174a03"`
[INFO] running `"docker" "rm" "-f" "e703b9f4fb5d3d62252a125672813cd11b57282e18db629669987dbafb174a03"`
[INFO] [stdout] e703b9f4fb5d3d62252a125672813cd11b57282e18db629669987dbafb174a03
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.38-1/worker-0/beta-2019-08-13:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/ajames72/rust-basics:/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" "+beta-2019-08-13" "test" "--frozen"`
[INFO] [stdout] e441d1512cdac7549014b0519f67fedbab3527fda02f70df3b64488a9040cf6c
[INFO] running `"docker" "start" "-a" "e441d1512cdac7549014b0519f67fedbab3527fda02f70df3b64488a9040cf6c"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running /opt/crater/target/debug/deps/rust_basics-ee9104bdc7b2e69a
[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" "e441d1512cdac7549014b0519f67fedbab3527fda02f70df3b64488a9040cf6c"`
[INFO] running `"docker" "rm" "-f" "e441d1512cdac7549014b0519f67fedbab3527fda02f70df3b64488a9040cf6c"`
[INFO] [stdout] e441d1512cdac7549014b0519f67fedbab3527fda02f70df3b64488a9040cf6c