[INFO] cloning repository https://github.com/shuqiangzhou/rust_study
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/shuqiangzhou/rust_study" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshuqiangzhou%2Frust_study", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshuqiangzhou%2Frust_study'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4fefc8853dfd148d162cb45558e4f3fa90e1293b
[INFO] testing shuqiangzhou/rust_study against 1.55.0 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshuqiangzhou%2Frust_study" "/workspace/builds/worker-86/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-86/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/shuqiangzhou/rust_study on toolchain 1.55.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/shuqiangzhou/rust_study
[INFO] finished tweaking git repo https://github.com/shuqiangzhou/rust_study
[INFO] tweaked toml for git repo https://github.com/shuqiangzhou/rust_study written to /workspace/builds/worker-86/source/Cargo.toml
[INFO] crate git repo https://github.com/shuqiangzhou/rust_study already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.55.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1160fa35792e6a306ec6f4a1c9d99a71ee6b163671843a84b6b27d77f9501188
[INFO] running `Command { std: "docker" "start" "-a" "1160fa35792e6a306ec6f4a1c9d99a71ee6b163671843a84b6b27d77f9501188", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1160fa35792e6a306ec6f4a1c9d99a71ee6b163671843a84b6b27d77f9501188", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1160fa35792e6a306ec6f4a1c9d99a71ee6b163671843a84b6b27d77f9501188", kill_on_drop: false }`
[INFO] [stdout] 1160fa35792e6a306ec6f4a1c9d99a71ee6b163671843a84b6b27d77f9501188
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5be31d0c605c67ee5ecb89fc1b34ec1969dd97a99c00a9c4c6abc5a5808a158b
[INFO] running `Command { std: "docker" "start" "-a" "5be31d0c605c67ee5ecb89fc1b34ec1969dd97a99c00a9c4c6abc5a5808a158b", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rust_study v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/bin/io.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut f = File::open("foo.txt").unwrap();
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 48.15s
[INFO] running `Command { std: "docker" "inspect" "5be31d0c605c67ee5ecb89fc1b34ec1969dd97a99c00a9c4c6abc5a5808a158b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5be31d0c605c67ee5ecb89fc1b34ec1969dd97a99c00a9c4c6abc5a5808a158b", kill_on_drop: false }`
[INFO] [stdout] 5be31d0c605c67ee5ecb89fc1b34ec1969dd97a99c00a9c4c6abc5a5808a158b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 37cc1bb67b7417c0089da0bb6dfbc82518c6fdc37ade59cbd3ff3a64d603472d
[INFO] running `Command { std: "docker" "start" "-a" "37cc1bb67b7417c0089da0bb6dfbc82518c6fdc37ade59cbd3ff3a64d603472d", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling rust_study v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/bin/io.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |     let mut f = File::open("foo.txt").unwrap();
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.84s
[INFO] running `Command { std: "docker" "inspect" "37cc1bb67b7417c0089da0bb6dfbc82518c6fdc37ade59cbd3ff3a64d603472d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "37cc1bb67b7417c0089da0bb6dfbc82518c6fdc37ade59cbd3ff3a64d603472d", kill_on_drop: false }`
[INFO] [stdout] 37cc1bb67b7417c0089da0bb6dfbc82518c6fdc37ade59cbd3ff3a64d603472d
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-86/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+1.55.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] c38eae210a417683c6ab23023d6d9502dd4443eadf8613346caa33436dec9e16
[INFO] running `Command { std: "docker" "start" "-a" "c38eae210a417683c6ab23023d6d9502dd4443eadf8613346caa33436dec9e16", kill_on_drop: false }`
[INFO] [stderr] warning: variable does not need to be mutable
[INFO] [stderr]   --> src/bin/io.rs:14:9
[INFO] [stderr]    |
[INFO] [stderr] 14 |     let mut f = File::open("foo.txt").unwrap();
[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] warning: `rust_study` (bin "io" test) generated 1 warning
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.03s
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/io-1ea4bc66aa920012)
[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; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/panic-ffd2c4f31a754887)
[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; finished in 0.00s
[INFO] [stdout] 
[INFO] [stderr]      Running unittests (/opt/rustwide/target/debug/deps/rust_study-976a0edcd64ab48f)
[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; finished in 0.00s
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "c38eae210a417683c6ab23023d6d9502dd4443eadf8613346caa33436dec9e16", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c38eae210a417683c6ab23023d6d9502dd4443eadf8613346caa33436dec9e16", kill_on_drop: false }`
[INFO] [stdout] c38eae210a417683c6ab23023d6d9502dd4443eadf8613346caa33436dec9e16