[INFO] cloning repository https://github.com/dowoncha/blockchain
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/dowoncha/blockchain" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdowoncha%2Fblockchain", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdowoncha%2Fblockchain'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] ff19cd4580e801c87e6f18dd61ff7e394cd5ce16
[INFO] checking dowoncha/blockchain against master#dfd7b8d03fb93d0e03147d28b3be6d93260fa94d for pr-87050
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fdowoncha%2Fblockchain" "/workspace/builds/worker-13/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-13/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/dowoncha/blockchain on toolchain dfd7b8d03fb93d0e03147d28b3be6d93260fa94d
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/dowoncha/blockchain
[INFO] finished tweaking git repo https://github.com/dowoncha/blockchain
[INFO] tweaked toml for git repo https://github.com/dowoncha/blockchain written to /workspace/builds/worker-13/source/Cargo.toml
[INFO] crate git repo https://github.com/dowoncha/blockchain already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "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] ac0eb90438014b2621f286f935f6a804f1f45b25fcb0aab38a326d17745a6778
[INFO] running `Command { std: "docker" "start" "-a" "ac0eb90438014b2621f286f935f6a804f1f45b25fcb0aab38a326d17745a6778", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ac0eb90438014b2621f286f935f6a804f1f45b25fcb0aab38a326d17745a6778", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ac0eb90438014b2621f286f935f6a804f1f45b25fcb0aab38a326d17745a6778", kill_on_drop: false }`
[INFO] [stdout] ac0eb90438014b2621f286f935f6a804f1f45b25fcb0aab38a326d17745a6778
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-13/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=forbid" "-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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+dfd7b8d03fb93d0e03147d28b3be6d93260fa94d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 804cbdf49f10e745a4759dc3fc076cd04cc48fddd7c6dc8c0bc60c1cb64067da
[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" "804cbdf49f10e745a4759dc3fc076cd04cc48fddd7c6dc8c0bc60c1cb64067da", kill_on_drop: false }`
[INFO] [stderr]     Checking libc v0.2.41
[INFO] [stderr]     Checking rand v0.4.2
[INFO] [stderr]     Checking time v0.1.40
[INFO] [stderr]     Checking rand v0.3.22
[INFO] [stderr]     Checking rust-crypto v0.2.36
[INFO] [stderr]     Checking blockchain v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: associated function is never used: `blocks`
[INFO] [stdout]   --> src/main.rs:82:12
[INFO] [stdout]    |
[INFO] [stdout] 82 |     pub fn blocks(&self) -> &[Block] {
[INFO] [stdout]    |            ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:131:13
[INFO] [stdout]     |
[INFO] [stdout] 131 |             writeln!(f, "Block {} Hash: {}", index, block.hash());
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `blocks`
[INFO] [stdout]   --> src/main.rs:82:12
[INFO] [stdout]    |
[INFO] [stdout] 82 |     pub fn blocks(&self) -> &[Block] {
[INFO] [stdout]    |            ^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]    --> src/main.rs:131:13
[INFO] [stdout]     |
[INFO] [stdout] 131 |             writeln!(f, "Block {} Hash: {}", index, block.hash());
[INFO] [stdout]     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]     = note: this warning originates in the macro `writeln` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 7.60s
[INFO] running `Command { std: "docker" "inspect" "804cbdf49f10e745a4759dc3fc076cd04cc48fddd7c6dc8c0bc60c1cb64067da", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "804cbdf49f10e745a4759dc3fc076cd04cc48fddd7c6dc8c0bc60c1cb64067da", kill_on_drop: false }`
[INFO] [stdout] 804cbdf49f10e745a4759dc3fc076cd04cc48fddd7c6dc8c0bc60c1cb64067da