[INFO] fetching crate visiting_ref 0.2.0...
[INFO] checking visiting_ref-0.2.0 against try#15a786332e2f0dd343b226ab6bb8ec028a350f73 for pr-81782
[INFO] extracting crate visiting_ref 0.2.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate visiting_ref 0.2.0 on toolchain 15a786332e2f0dd343b226ab6bb8ec028a350f73
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate visiting_ref 0.2.0
[INFO] finished tweaking crates.io crate visiting_ref 0.2.0
[INFO] tweaked toml for crates.io crate visiting_ref 0.2.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded futures-macro v0.3.13
[INFO] [stderr]   Downloaded tokio v0.2.25
[INFO] [stderr]   Downloaded bytes v0.5.6
[INFO] [stderr]   Downloaded tokio-macros v0.2.6
[INFO] [stderr]   Downloaded futures v0.3.13
[INFO] [stderr]   Downloaded proc-macro-nested v0.1.7
[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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d995e1d6d31cc9223cf954bafa1b12854e13644dd4ca408d644b965d36f436e0
[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" "d995e1d6d31cc9223cf954bafa1b12854e13644dd4ca408d644b965d36f436e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d995e1d6d31cc9223cf954bafa1b12854e13644dd4ca408d644b965d36f436e0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d995e1d6d31cc9223cf954bafa1b12854e13644dd4ca408d644b965d36f436e0", kill_on_drop: false }`
[INFO] [stdout] d995e1d6d31cc9223cf954bafa1b12854e13644dd4ca408d644b965d36f436e0
[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:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+15a786332e2f0dd343b226ab6bb8ec028a350f73" "check" "--frozen" "--all" "--all-targets" "--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] b92ce57ce8e96c0b32c19eb2712bf4159a84a7aa834aec54fbbf42cc0ab79a79
[INFO] running `Command { std: "docker" "start" "-a" "b92ce57ce8e96c0b32c19eb2712bf4159a84a7aa834aec54fbbf42cc0ab79a79", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]    Compiling proc-macro-nested v0.1.7
[INFO] [stderr]     Checking futures-sink v0.3.13
[INFO] [stderr]     Checking futures-core v0.3.13
[INFO] [stderr]    Compiling libc v0.2.86
[INFO] [stderr]     Checking futures-task v0.3.13
[INFO] [stderr]     Checking bytes v0.5.6
[INFO] [stderr]     Checking pin-project-lite v0.1.11
[INFO] [stderr]     Checking memchr v2.3.4
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]     Checking futures-channel v0.3.13
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]    Compiling futures-macro v0.3.13
[INFO] [stderr]    Compiling tokio-macros v0.2.6
[INFO] [stderr]     Checking tokio v0.2.25
[INFO] [stderr]     Checking futures-util v0.3.13
[INFO] [stderr]     Checking futures-executor v0.3.13
[INFO] [stderr]     Checking visiting_ref v0.2.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking futures v0.3.13
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 22.90s
[INFO] running `Command { std: "docker" "inspect" "b92ce57ce8e96c0b32c19eb2712bf4159a84a7aa834aec54fbbf42cc0ab79a79", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b92ce57ce8e96c0b32c19eb2712bf4159a84a7aa834aec54fbbf42cc0ab79a79", kill_on_drop: false }`
[INFO] [stdout] b92ce57ce8e96c0b32c19eb2712bf4159a84a7aa834aec54fbbf42cc0ab79a79