[INFO] cloning repository https://github.com/HsiangSun/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/HsiangSun/rust_study" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHsiangSun%2Frust_study", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHsiangSun%2Frust_study'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cafc19252292e98dc652fbf9ef9a99bf8a5f4cea
[INFO] testing HsiangSun/rust_study against 1.49.0 for beta-1.50-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FHsiangSun%2Frust_study" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/HsiangSun/rust_study on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/HsiangSun/rust_study
[INFO] finished tweaking git repo https://github.com/HsiangSun/rust_study
[INFO] tweaked toml for git repo https://github.com/HsiangSun/rust_study written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/HsiangSun/rust_study already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4d01c8e91e979b9053893e465f400bf89877711f4d315038f699f7103f4d6cc6
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "4d01c8e91e979b9053893e465f400bf89877711f4d315038f699f7103f4d6cc6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4d01c8e91e979b9053893e465f400bf89877711f4d315038f699f7103f4d6cc6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d01c8e91e979b9053893e465f400bf89877711f4d315038f699f7103f4d6cc6", kill_on_drop: false }`
[INFO] [stdout] 4d01c8e91e979b9053893e465f400bf89877711f4d315038f699f7103f4d6cc6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 947ca75bfdf6f38d105340e871fd1859c72a544c7eb1e925d1af8614ffe114b4
[INFO] running `Command { std: "docker" "start" "-a" "947ca75bfdf6f38d105340e871fd1859c72a544c7eb1e925d1af8614ffe114b4", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling study01 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]  --> src/io.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let f = File::create("./rust.txt").unwrap();
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` 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 1.32s
[INFO] running `Command { std: "docker" "inspect" "947ca75bfdf6f38d105340e871fd1859c72a544c7eb1e925d1af8614ffe114b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "947ca75bfdf6f38d105340e871fd1859c72a544c7eb1e925d1af8614ffe114b4", kill_on_drop: false }`
[INFO] [stdout] 947ca75bfdf6f38d105340e871fd1859c72a544c7eb1e925d1af8614ffe114b4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 454c93ddaf38ec5ab402a89d2e2cc69927ea238f33dd2fcf3ed4419f98019a59
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "454c93ddaf38ec5ab402a89d2e2cc69927ea238f33dd2fcf3ed4419f98019a59", kill_on_drop: false }`
[INFO] [stderr]    Compiling study01 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `f`
[INFO] [stdout]  --> src/io.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let f = File::create("./rust.txt").unwrap();
[INFO] [stdout]   |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` 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 0.77s
[INFO] running `Command { std: "docker" "inspect" "454c93ddaf38ec5ab402a89d2e2cc69927ea238f33dd2fcf3ed4419f98019a59", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "454c93ddaf38ec5ab402a89d2e2cc69927ea238f33dd2fcf3ed4419f98019a59", kill_on_drop: false }`
[INFO] [stdout] 454c93ddaf38ec5ab402a89d2e2cc69927ea238f33dd2fcf3ed4419f98019a59
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:c8ac004eab7d63a0ad09a2dde3d3353ba464f767bee4de425dc8f74c46a1905e" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] f39f0b85e321f8795321d90e3fe0a522ddb80aaf9ff2aca869e60f709235b9d7
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "f39f0b85e321f8795321d90e3fe0a522ddb80aaf9ff2aca869e60f709235b9d7", kill_on_drop: false }`
[INFO] [stderr] warning: unused variable: `f`
[INFO] [stderr]  --> src/io.rs:4:9
[INFO] [stderr]   |
[INFO] [stderr] 4 |     let f = File::create("./rust.txt").unwrap();
[INFO] [stderr]   |         ^ help: if this is intentional, prefix it with an underscore: `_f`
[INFO] [stderr]   |
[INFO] [stderr]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.01s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/study01-eb6c35204dd2b261
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stdout] test io::unit_test ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "f39f0b85e321f8795321d90e3fe0a522ddb80aaf9ff2aca869e60f709235b9d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f39f0b85e321f8795321d90e3fe0a522ddb80aaf9ff2aca869e60f709235b9d7", kill_on_drop: false }`
[INFO] [stdout] f39f0b85e321f8795321d90e3fe0a522ddb80aaf9ff2aca869e60f709235b9d7