[INFO] fetching crate derive_builder_core 0.10.2...
[INFO] testing derive_builder_core-0.10.2 against master#a77da2d454e6caa227a85b16410b95f93495e7e0 for pr-91031
[INFO] extracting crate derive_builder_core 0.10.2 into /workspace/builds/worker-54/source
[INFO] validating manifest of crates.io crate derive_builder_core 0.10.2 on toolchain a77da2d454e6caa227a85b16410b95f93495e7e0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate derive_builder_core 0.10.2
[INFO] finished tweaking crates.io crate derive_builder_core 0.10.2
[INFO] tweaked toml for crates.io crate derive_builder_core 0.10.2 written to /workspace/builds/worker-54/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "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" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "fetch" "--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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 36397e40c9ebe27d9df6886cb92c5711bdcc439fc9d1f8cf0609c2ce62225b5c
[INFO] running `Command { std: "docker" "start" "-a" "36397e40c9ebe27d9df6886cb92c5711bdcc439fc9d1f8cf0609c2ce62225b5c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "36397e40c9ebe27d9df6886cb92c5711bdcc439fc9d1f8cf0609c2ce62225b5c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "36397e40c9ebe27d9df6886cb92c5711bdcc439fc9d1f8cf0609c2ce62225b5c", kill_on_drop: false }`
[INFO] [stdout] 36397e40c9ebe27d9df6886cb92c5711bdcc439fc9d1f8cf0609c2ce62225b5c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-54/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@sha256:5736fa189c1c60b01babf4b8b698fe57b6ecc41933a7ff2e0b8d7a221459412b" "/opt/rustwide/cargo-home/bin/cargo" "+a77da2d454e6caa227a85b16410b95f93495e7e0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 0d3bdd3d5f4a2ec5937435f1c1061af369073bb2b67fa0390cd1ad45b9450faa
[INFO] running `Command { std: "docker" "start" "-a" "0d3bdd3d5f4a2ec5937435f1c1061af369073bb2b67fa0390cd1ad45b9450faa", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.32
[INFO] [stderr]    Compiling unicode-xid v0.2.2
[INFO] [stderr]    Compiling quote v1.0.10
[INFO] [stderr]    Compiling syn v1.0.81
[INFO] [stderr]    Compiling darling_core v0.12.4
[INFO] [stderr]    Compiling darling_macro v0.12.4
[INFO] [stderr]    Compiling darling v0.12.4
[INFO] [stderr]    Compiling derive_builder_core v0.10.2 (/opt/rustwide/workdir)
[INFO] [stdout] error: field is never read: `vis`
[INFO] [stdout]    --> src/macro_options/darling_opts.rs:213:5
[INFO] [stdout]     |
[INFO] [stdout] 213 |     vis: syn::Visibility,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:18:9
[INFO] [stdout]     |
[INFO] [stdout] 18  | #![deny(warnings, missing_docs)]
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     = note: `#[deny(dead_code)]` implied by `#[deny(warnings)]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: field is never read: `attrs`
[INFO] [stdout]    --> src/macro_options/darling_opts.rs:264:5
[INFO] [stdout]     |
[INFO] [stdout] 264 |     attrs: Vec<Attribute>,
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `derive_builder_core` due to 3 previous errors
[INFO] running `Command { std: "docker" "inspect" "0d3bdd3d5f4a2ec5937435f1c1061af369073bb2b67fa0390cd1ad45b9450faa", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0d3bdd3d5f4a2ec5937435f1c1061af369073bb2b67fa0390cd1ad45b9450faa", kill_on_drop: false }`
[INFO] [stdout] 0d3bdd3d5f4a2ec5937435f1c1061af369073bb2b67fa0390cd1ad45b9450faa