[INFO] updating cached repository https://github.com/a7p/learn-rust-stringmixer
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] fcb40481b878e6596a5284902fa4cf1a2a04252e
[INFO] testing a7p/learn-rust-stringmixer against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fa7p%2Flearn-rust-stringmixer" "work/builds/worker-1/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/a7p/learn-rust-stringmixer on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/a7p/learn-rust-stringmixer
[INFO] finished tweaking git repo https://github.com/a7p/learn-rust-stringmixer
[INFO] tweaked toml for git repo https://github.com/a7p/learn-rust-stringmixer written to work/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/a7p/learn-rust-stringmixer already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr] error: the lock file /big/crater/work/builds/worker-1/source/Cargo.lock needs to be updated but --locked was passed to prevent this
[INFO] the lockfile is outdated, regenerating it
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-1/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] fa7d284836a5aa7899994f2ce5386f6814566d9ca0522a1487eb395927a50bf5
[INFO] running `"docker" "start" "-a" "fa7d284836a5aa7899994f2ce5386f6814566d9ca0522a1487eb395927a50bf5"`
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling stringmixer v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:20:13
[INFO] [stderr]    |
[INFO] [stderr] 20 |         let mut v = &mut g[1..l];
[INFO] [stderr]    |             ----^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.21s
[INFO] running `"docker" "inspect" "fa7d284836a5aa7899994f2ce5386f6814566d9ca0522a1487eb395927a50bf5"`
[INFO] running `"docker" "rm" "-f" "fa7d284836a5aa7899994f2ce5386f6814566d9ca0522a1487eb395927a50bf5"`
[INFO] [stdout] fa7d284836a5aa7899994f2ce5386f6814566d9ca0522a1487eb395927a50bf5
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-1/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "test" "--frozen" "--no-run"`
[INFO] [stdout] 6c8284f5a0ffe4929a06b302cd694a6326cd54cd142b5e3b70d299551cffd606
[INFO] running `"docker" "start" "-a" "6c8284f5a0ffe4929a06b302cd694a6326cd54cd142b5e3b70d299551cffd606"`
[INFO] [stderr]    Compiling stringmixer v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/main.rs:20:13
[INFO] [stderr]    |
[INFO] [stderr] 20 |         let mut v = &mut g[1..l];
[INFO] [stderr]    |             ----^
[INFO] [stderr]    |             |
[INFO] [stderr]    |             help: remove this `mut`
[INFO] [stderr]    |
[INFO] [stderr]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.89s
[INFO] running `"docker" "inspect" "6c8284f5a0ffe4929a06b302cd694a6326cd54cd142b5e3b70d299551cffd606"`
[INFO] running `"docker" "rm" "-f" "6c8284f5a0ffe4929a06b302cd694a6326cd54cd142b5e3b70d299551cffd606"`
[INFO] [stdout] 6c8284f5a0ffe4929a06b302cd694a6326cd54cd142b5e3b70d299551cffd606
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-1/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "test" "--frozen"`
[INFO] [stdout] 46f2544f7b6de8db4d4ac5bf79cd277cba56377e25f2c5ff7140ab448487c802
[INFO] running `"docker" "start" "-a" "46f2544f7b6de8db4d4ac5bf79cd277cba56377e25f2c5ff7140ab448487c802"`
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/stringmixer-3d2f8f256dfa6498
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test test_same ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/mixer-35afe2ff8ff7f8c0
[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" "46f2544f7b6de8db4d4ac5bf79cd277cba56377e25f2c5ff7140ab448487c802"`
[INFO] running `"docker" "rm" "-f" "46f2544f7b6de8db4d4ac5bf79cd277cba56377e25f2c5ff7140ab448487c802"`
[INFO] [stdout] 46f2544f7b6de8db4d4ac5bf79cd277cba56377e25f2c5ff7140ab448487c802