[INFO] fetching crate gc-arena 0.2.0...
[INFO] checking gc-arena-0.2.0 against master#6526e5c772f2da07db745c94ca6bb0a591a39ba4 for pr-80920
[INFO] extracting crate gc-arena 0.2.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate gc-arena 0.2.0 on toolchain 6526e5c772f2da07db745c94ca6bb0a591a39ba4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate gc-arena 0.2.0
[INFO] finished tweaking crates.io crate gc-arena 0.2.0
[INFO] tweaked toml for crates.io crate gc-arena 0.2.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7bc5d36db493eee79dcf440e6b69ffd09fba70c710b1c235b471d7a085c2a0fb
[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" "7bc5d36db493eee79dcf440e6b69ffd09fba70c710b1c235b471d7a085c2a0fb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7bc5d36db493eee79dcf440e6b69ffd09fba70c710b1c235b471d7a085c2a0fb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7bc5d36db493eee79dcf440e6b69ffd09fba70c710b1c235b471d7a085c2a0fb", kill_on_drop: false }`
[INFO] [stdout] 7bc5d36db493eee79dcf440e6b69ffd09fba70c710b1c235b471d7a085c2a0fb
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ac9c33940af99fab089cfc0fce92356d0f812ef90f45c30078ea6f84c929a533
[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" "ac9c33940af99fab089cfc0fce92356d0f812ef90f45c30078ea6f84c929a533", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]     Checking gc-arena v0.2.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stdout] warning: bounds on `T: Drop` are useless, consider instead using `std::mem::needs_drop` to detect if a type has a destructor
[INFO] [stdout]  --> src/no_drop.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 | impl<T: Drop> MustNotImplDrop for T {}
[INFO] [stdout]   |         ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(drop_bounds)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: bounds on `T: Drop` are useless, consider instead using `std::mem::needs_drop` to detect if a type has a destructor
[INFO] [stdout]  --> src/no_drop.rs:7:9
[INFO] [stdout]   |
[INFO] [stdout] 7 | impl<T: Drop> MustNotImplDrop for T {}
[INFO] [stdout]   |         ^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(drop_bounds)]` 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 2.24s
[INFO] running `Command { std: "docker" "inspect" "ac9c33940af99fab089cfc0fce92356d0f812ef90f45c30078ea6f84c929a533", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ac9c33940af99fab089cfc0fce92356d0f812ef90f45c30078ea6f84c929a533", kill_on_drop: false }`
[INFO] [stdout] ac9c33940af99fab089cfc0fce92356d0f812ef90f45c30078ea6f84c929a533