[INFO] fetching crate farbfeld 0.3.1...
[INFO] checking farbfeld-0.3.1 against master#a5f164faad4a2fed606b8160fd7ecd2d5cbba381 for pr-84920
[INFO] extracting crate farbfeld 0.3.1 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate farbfeld 0.3.1 on toolchain a5f164faad4a2fed606b8160fd7ecd2d5cbba381
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate farbfeld 0.3.1
[INFO] finished tweaking crates.io crate farbfeld 0.3.1
[INFO] tweaked toml for crates.io crate farbfeld 0.3.1 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "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" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4ca227bbb34e7c3b8bd309b304027b6abeb4a38196d4f4903802e29908cf3ca8
[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" "4ca227bbb34e7c3b8bd309b304027b6abeb4a38196d4f4903802e29908cf3ca8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4ca227bbb34e7c3b8bd309b304027b6abeb4a38196d4f4903802e29908cf3ca8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4ca227bbb34e7c3b8bd309b304027b6abeb4a38196d4f4903802e29908cf3ca8", kill_on_drop: false }`
[INFO] [stdout] 4ca227bbb34e7c3b8bd309b304027b6abeb4a38196d4f4903802e29908cf3ca8
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+a5f164faad4a2fed606b8160fd7ecd2d5cbba381" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] afd65e7b8c0b872aebef3c5ed2d6f596b5679fda74d4233e64a913c848569566
[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" "afd65e7b8c0b872aebef3c5ed2d6f596b5679fda74d4233e64a913c848569566", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking byteorder v1.4.3
[INFO] [stderr]     Checking farbfeld v0.3.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:68:33
[INFO] [stdout]    |
[INFO] [stdout] 68 |     fn cause (&self) -> Option<&error::Error> {
[INFO] [stdout]    |                                 ^^^^^^^^^^^^ help: use `dyn`: `dyn error::Error`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/lib.rs:68:33
[INFO] [stdout]    |
[INFO] [stdout] 68 |     fn cause (&self) -> Option<&error::Error> {
[INFO] [stdout]    |                                 ^^^^^^^^^^^^ help: use `dyn`: `dyn error::Error`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout]    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2021 edition!
[INFO] [stdout]    = note: for more information, see issue #80165 <https://github.com/rust-lang/rust/issues/80165>
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: panic message is not a string literal
[INFO] [stdout]   --> src/tests.rs:22:16
[INFO] [stdout]    |
[INFO] [stdout] 22 |         panic!(e)
[INFO] [stdout]    |                ^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_fmt_panic)]` on by default
[INFO] [stdout]    = note: this is no longer accepted in Rust 2021
[INFO] [stdout] help: add a "{}" format string to Display the message
[INFO] [stdout]    |
[INFO] [stdout] 22 |         panic!("{}", e)
[INFO] [stdout]    |                ^^^^^
[INFO] [stdout] help: or use std::panic::panic_any instead
[INFO] [stdout]    |
[INFO] [stdout] 22 |         std::panic::panic_any(e)
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.14s
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "afd65e7b8c0b872aebef3c5ed2d6f596b5679fda74d4233e64a913c848569566", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "afd65e7b8c0b872aebef3c5ed2d6f596b5679fda74d4233e64a913c848569566", kill_on_drop: false }`
[INFO] [stdout] afd65e7b8c0b872aebef3c5ed2d6f596b5679fda74d4233e64a913c848569566