[INFO] fetching crate buffer_io 1.0.3...
[INFO] testing buffer_io-1.0.3 against 1.49.0 for beta-1.50-1
[INFO] extracting crate buffer_io 1.0.3 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate buffer_io 1.0.3 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 crates.io crate buffer_io 1.0.3
[INFO] finished tweaking crates.io crate buffer_io 1.0.3
[INFO] tweaked toml for crates.io crate buffer_io 1.0.3 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "metadata" "--no-deps" "--format-version=1", 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] b816371bedbe8e12a7bc0d57aad121305f0741bfa66a9c48f0046a4f8f66473e
[INFO] running `Command { std: "docker" "start" "-a" "b816371bedbe8e12a7bc0d57aad121305f0741bfa66a9c48f0046a4f8f66473e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b816371bedbe8e12a7bc0d57aad121305f0741bfa66a9c48f0046a4f8f66473e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b816371bedbe8e12a7bc0d57aad121305f0741bfa66a9c48f0046a4f8f66473e", kill_on_drop: false }`
[INFO] [stdout] b816371bedbe8e12a7bc0d57aad121305f0741bfa66a9c48f0046a4f8f66473e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b9292971781fdcc52114f4c50f22ff9da387a2d75cbff3df2ba5255ae4531144
[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" "b9292971781fdcc52114f4c50f22ff9da387a2d75cbff3df2ba5255ae4531144", kill_on_drop: false }`
[INFO] [stderr]    Compiling buffer_io v1.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `b` is never read
[INFO] [stdout]    --> src/lib.rs:211:17
[INFO] [stdout]     |
[INFO] [stdout] 211 |             let mut b: u8 = 0;
[INFO] [stdout]     |                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.66s
[INFO] running `Command { std: "docker" "inspect" "b9292971781fdcc52114f4c50f22ff9da387a2d75cbff3df2ba5255ae4531144", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b9292971781fdcc52114f4c50f22ff9da387a2d75cbff3df2ba5255ae4531144", kill_on_drop: false }`
[INFO] [stdout] b9292971781fdcc52114f4c50f22ff9da387a2d75cbff3df2ba5255ae4531144
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 4d4e3daf3b2fd50e88e58f01e8e98c0b22a9d5bbc58bb497a53b125bda85c8b6
[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" "4d4e3daf3b2fd50e88e58f01e8e98c0b22a9d5bbc58bb497a53b125bda85c8b6", kill_on_drop: false }`
[INFO] [stdout] warning: value assigned to `b` is never read
[INFO] [stdout]    --> src/lib.rs:211:17
[INFO] [stdout]     |
[INFO] [stdout] 211 |             let mut b: u8 = 0;
[INFO] [stdout]     |                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling buffer_io v1.0.3 (/opt/rustwide/workdir)
[INFO] [stdout] warning: value assigned to `b` is never read
[INFO] [stdout]    --> src/lib.rs:211:17
[INFO] [stdout]     |
[INFO] [stdout] 211 |             let mut b: u8 = 0;
[INFO] [stdout]     |                 ^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]     = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 1.16s
[INFO] running `Command { std: "docker" "inspect" "4d4e3daf3b2fd50e88e58f01e8e98c0b22a9d5bbc58bb497a53b125bda85c8b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4d4e3daf3b2fd50e88e58f01e8e98c0b22a9d5bbc58bb497a53b125bda85c8b6", kill_on_drop: false }`
[INFO] [stdout] 4d4e3daf3b2fd50e88e58f01e8e98c0b22a9d5bbc58bb497a53b125bda85c8b6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+1.49.0" "test" "--frozen", kill_on_drop: false }`
[INFO] [stdout] d9fa5fd962ff623742568a6fbfcd8790667596e176058f3e7f3c8d64a371f6cd
[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" "d9fa5fd962ff623742568a6fbfcd8790667596e176058f3e7f3c8d64a371f6cd", kill_on_drop: false }`
[INFO] [stderr] warning: value assigned to `b` is never read
[INFO] [stderr]    --> src/lib.rs:211:17
[INFO] [stderr]     |
[INFO] [stderr] 211 |             let mut b: u8 = 0;
[INFO] [stderr]     |                 ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]     = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr] warning: value assigned to `b` is never read
[INFO] [stderr]    --> src/lib.rs:211:17
[INFO] [stderr]     |
[INFO] [stderr] 211 |             let mut b: u8 = 0;
[INFO] [stderr]     |                 ^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: `#[warn(unused_assignments)]` on by default
[INFO] [stderr]     = help: maybe it is overwritten before being read?
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.04s
[INFO] [stderr]      Running /opt/rustwide/target/debug/deps/buffer_io-405f16fc41146c7a
[INFO] [stdout] 
[INFO] [stdout] running 1 test
[INFO] [stderr]    Doc-tests buffer_io
[INFO] [stdout] test tests::it_works ... ok
[INFO] [stdout] 
[INFO] [stdout] test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out
[INFO] [stdout] 
[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 `Command { std: "docker" "inspect" "d9fa5fd962ff623742568a6fbfcd8790667596e176058f3e7f3c8d64a371f6cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d9fa5fd962ff623742568a6fbfcd8790667596e176058f3e7f3c8d64a371f6cd", kill_on_drop: false }`
[INFO] [stdout] d9fa5fd962ff623742568a6fbfcd8790667596e176058f3e7f3c8d64a371f6cd