[INFO] updating cached repository caryssaperez/learn-rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/caryssaperez/learn-rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/caryssaperez/learn-rust" "work/ex/beta-1.37-6/sources/1.36.0/gh/caryssaperez/learn-rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/caryssaperez/learn-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/caryssaperez/learn-rust" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/caryssaperez/learn-rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/caryssaperez/learn-rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] b22b664e5c0caaf4842a994978d9126fc6be9324
[INFO] sha for GitHub repo caryssaperez/learn-rust: b22b664e5c0caaf4842a994978d9126fc6be9324
[INFO] validating manifest of caryssaperez/learn-rust on toolchain 1.36.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of caryssaperez/learn-rust on toolchain beta-2019-07-23
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing caryssaperez/learn-rust
[INFO] finished frobbing caryssaperez/learn-rust
[INFO] frobbed toml for caryssaperez/learn-rust written to work/ex/beta-1.37-6/sources/1.36.0/gh/caryssaperez/learn-rust/Cargo.toml
[INFO] started frobbing caryssaperez/learn-rust
[INFO] finished frobbing caryssaperez/learn-rust
[INFO] frobbed toml for caryssaperez/learn-rust written to work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/caryssaperez/learn-rust/Cargo.toml
[INFO] crate caryssaperez/learn-rust already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.36.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-07-23" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] testing caryssaperez/learn-rust against 1.36.0 for beta-1.37-6
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/beta-1.37-6/worker-6/1.36.0:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/beta-1.37-6/sources/1.36.0/gh/caryssaperez/learn-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" "+1.36.0" "build" "--frozen"`
[INFO] [stdout] 463b5f21231166fa48ee323a4428f9daa410e51f415c1afde015a50d86ddd7cf
[INFO] running `"docker" "start" "-a" "463b5f21231166fa48ee323a4428f9daa410e51f415c1afde015a50d86ddd7cf"`
[INFO] [stderr]    Compiling learn-rust v0.1.0 (/opt/crater/workdir)
[INFO] [stderr] warning: unused import: `learn_rust::ThreadPool`
[INFO] [stderr]  --> src/bin/main.rs:1:5
[INFO] [stderr]   |
[INFO] [stderr] 1 | use learn_rust::ThreadPool;
[INFO] [stderr]   |     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]   |
[INFO] [stderr]   = note: #[warn(unused_imports)] on by default
[INFO] [stderr] 
[INFO] [stderr] error[E0601]: `main` function not found in crate `main`
[INFO] [stderr]   |
[INFO] [stderr]   = note: consider adding a `main` function to `src/bin/main.rs`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0601`.
[INFO] [stderr] error: Could not compile `learn-rust`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "463b5f21231166fa48ee323a4428f9daa410e51f415c1afde015a50d86ddd7cf"`
[INFO] running `"docker" "rm" "-f" "463b5f21231166fa48ee323a4428f9daa410e51f415c1afde015a50d86ddd7cf"`
[INFO] [stdout] 463b5f21231166fa48ee323a4428f9daa410e51f415c1afde015a50d86ddd7cf