[INFO] fetching crate serde-helpers 0.1.0...
[INFO] checking serde-helpers-0.1.0 against master#4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5 for pr-81174
[INFO] extracting crate serde-helpers 0.1.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate serde-helpers 0.1.0 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 serde-helpers 0.1.0
[INFO] finished tweaking crates.io crate serde-helpers 0.1.0
[INFO] tweaked toml for crates.io crate serde-helpers 0.1.0 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] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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] 7e240c42cf5f04810d85d0fe0b2278ce1f6751b0d63402fde7dea5cdcc648c3a
[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" "7e240c42cf5f04810d85d0fe0b2278ce1f6751b0d63402fde7dea5cdcc648c3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7e240c42cf5f04810d85d0fe0b2278ce1f6751b0d63402fde7dea5cdcc648c3a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e240c42cf5f04810d85d0fe0b2278ce1f6751b0d63402fde7dea5cdcc648c3a", kill_on_drop: false }`
[INFO] [stdout] 7e240c42cf5f04810d85d0fe0b2278ce1f6751b0d63402fde7dea5cdcc648c3a
[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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] b76385970fbf71293c927a85088aad04858727f4ea626587bd4f713429ebc3cd
[INFO] running `Command { std: "docker" "start" "-a" "b76385970fbf71293c927a85088aad04858727f4ea626587bd4f713429ebc3cd", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.123
[INFO] [stderr]    Compiling serde_json v1.0.61
[INFO] [stderr]     Checking linked-hash-map v0.5.4
[INFO] [stderr]     Checking dtoa v0.4.7
[INFO] [stderr]     Checking yaml-rust v0.4.5
[INFO] [stderr]     Checking serde_yaml v0.7.5
[INFO] [stderr]     Checking serde-helpers v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/error.rs:24:23
[INFO] [stdout]    |
[INFO] [stdout] 24 |     cause: Option<Box<StdError>>,
[INFO] [stdout]    |                       ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/error.rs:56:32
[INFO] [stdout]    |
[INFO] [stdout] 56 |     fn cause(&self) -> Option<&StdError> {
[INFO] [stdout]    |                                ^^^^^^^^ help: use `dyn`: `dyn StdError`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/error.rs:31:30
[INFO] [stdout]    |
[INFO] [stdout] 31 |             description: err.description().to_string(),
[INFO] [stdout]    |                              ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(deprecated)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of deprecated associated function `std::error::Error::description`: use the Display impl or to_string()
[INFO] [stdout]   --> src/error.rs:40:30
[INFO] [stdout]    |
[INFO] [stdout] 40 |             description: err.description().to_string(),
[INFO] [stdout]    |                              ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 10.10s
[INFO] running `Command { std: "docker" "inspect" "b76385970fbf71293c927a85088aad04858727f4ea626587bd4f713429ebc3cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b76385970fbf71293c927a85088aad04858727f4ea626587bd4f713429ebc3cd", kill_on_drop: false }`
[INFO] [stdout] b76385970fbf71293c927a85088aad04858727f4ea626587bd4f713429ebc3cd