[INFO] fetching crate competitive-programming-rs 29.0.0...
[INFO] checking competitive-programming-rs-29.0.0 against master#4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5 for pr-81174
[INFO] extracting crate competitive-programming-rs 29.0.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate competitive-programming-rs 29.0.0 on toolchain 4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate competitive-programming-rs 29.0.0
[INFO] finished tweaking crates.io crate competitive-programming-rs 29.0.0
[INFO] tweaked toml for crates.io crate competitive-programming-rs 29.0.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "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" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "fetch" "--locked" "--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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded rand_hc v0.2.0
[INFO] [stderr]   Downloaded rand_chacha v0.2.2
[INFO] [stderr]   Downloaded getrandom v0.1.16
[INFO] [stderr]   Downloaded ppv-lite86 v0.2.10
[INFO] [stderr]   Downloaded rand v0.7.3
[INFO] [stderr]   Downloaded wasi v0.9.0+wasi-snapshot-preview1
[INFO] [stderr]   Downloaded rand_core v0.5.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0f1ec22b587a7cc376da3772544ee7122e0247c7b1cd73d79aebc9ff6b474982
[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" "0f1ec22b587a7cc376da3772544ee7122e0247c7b1cd73d79aebc9ff6b474982", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0f1ec22b587a7cc376da3772544ee7122e0247c7b1cd73d79aebc9ff6b474982", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0f1ec22b587a7cc376da3772544ee7122e0247c7b1cd73d79aebc9ff6b474982", kill_on_drop: false }`
[INFO] [stdout] 0f1ec22b587a7cc376da3772544ee7122e0247c7b1cd73d79aebc9ff6b474982
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 3bf610110707e9bc9864373a04eab60d3f03ceee87245632457c7c88bd631ad9
[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" "3bf610110707e9bc9864373a04eab60d3f03ceee87245632457c7c88bd631ad9", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling getrandom v0.1.16
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking ppv-lite86 v0.2.10
[INFO] [stderr]     Checking competitive-programming-rs v29.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `is_reversed`
[INFO] [stdout]   --> src/graph/min_cost_flow.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |         is_reversed: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stdout] warning: field is never read: `is_reversed`
[INFO] [stdout]   --> src/graph/min_cost_flow.rs:14:9
[INFO] [stdout]    |
[INFO] [stdout] 14 |         is_reversed: bool,
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` 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 5.17s
[INFO] running `Command { std: "docker" "inspect" "3bf610110707e9bc9864373a04eab60d3f03ceee87245632457c7c88bd631ad9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3bf610110707e9bc9864373a04eab60d3f03ceee87245632457c7c88bd631ad9", kill_on_drop: false }`
[INFO] [stdout] 3bf610110707e9bc9864373a04eab60d3f03ceee87245632457c7c88bd631ad9