[INFO] crate context-attribute 1.0.0 is already in cache
[INFO] testing context-attribute-1.0.0 against master#8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e for pr-74409
[INFO] extracting crate context-attribute 1.0.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate context-attribute 1.0.0 on toolchain 8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate context-attribute 1.0.0
[INFO] finished tweaking crates.io crate context-attribute 1.0.0
[INFO] tweaked toml for crates.io crate context-attribute 1.0.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "metadata" "--no-deps" "--format-version=1", 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] b09b484dd5731b716313f700c26d6307415cebeaac5ee68ac7bb383e191cf71a
[INFO] running `Command { std: "docker" "start" "-a" "b09b484dd5731b716313f700c26d6307415cebeaac5ee68ac7bb383e191cf71a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b09b484dd5731b716313f700c26d6307415cebeaac5ee68ac7bb383e191cf71a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b09b484dd5731b716313f700c26d6307415cebeaac5ee68ac7bb383e191cf71a", kill_on_drop: false }`
[INFO] [stdout] b09b484dd5731b716313f700c26d6307415cebeaac5ee68ac7bb383e191cf71a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env@sha256:38e1b949b06cde1964af550a6e548bd9b2b2ea170003ae122f8fc0886596cc07" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 71a46ec320b0a77841d07ea7b977c5794afe76e79556ba0b43d67fb7453bd0d3
[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" "71a46ec320b0a77841d07ea7b977c5794afe76e79556ba0b43d67fb7453bd0d3", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.73
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling backtrace v0.3.50
[INFO] [stderr]    Compiling failure v0.1.8
[INFO] [stderr]    Compiling context-attribute v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: unused extern crate
[INFO] [stdout]   --> src/lib.rs:45:1
[INFO] [stdout]    |
[INFO] [stdout] 45 | extern crate proc_macro;
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/lib.rs:39:45
[INFO] [stdout]    |
[INFO] [stdout] 39 | #![forbid(unsafe_code, future_incompatible, rust_2018_idioms)]
[INFO] [stdout]    |                                             ^^^^^^^^^^^^^^^^
[INFO] [stdout]    = note: `#[forbid(unused_extern_crates)]` implied by `#[forbid(rust_2018_idioms)]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `context-attribute`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "71a46ec320b0a77841d07ea7b977c5794afe76e79556ba0b43d67fb7453bd0d3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "71a46ec320b0a77841d07ea7b977c5794afe76e79556ba0b43d67fb7453bd0d3", kill_on_drop: false }`
[INFO] [stdout] 71a46ec320b0a77841d07ea7b977c5794afe76e79556ba0b43d67fb7453bd0d3