[INFO] crate runtime-attributes 0.3.0-alpha.6 is already in cache
[INFO] testing runtime-attributes-0.3.0-alpha.6 against master#8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e for pr-74409
[INFO] extracting crate runtime-attributes 0.3.0-alpha.6 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate runtime-attributes 0.3.0-alpha.6 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 runtime-attributes 0.3.0-alpha.6
[INFO] finished tweaking crates.io crate runtime-attributes 0.3.0-alpha.6
[INFO] tweaked toml for crates.io crate runtime-attributes 0.3.0-alpha.6 written to /workspace/builds/worker-5/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-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 37efadb2f601f0eedab9b4f47a866b984eafb8fb8b653fb3a5eb3137f504fd19
[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" "37efadb2f601f0eedab9b4f47a866b984eafb8fb8b653fb3a5eb3137f504fd19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "37efadb2f601f0eedab9b4f47a866b984eafb8fb8b653fb3a5eb3137f504fd19", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "37efadb2f601f0eedab9b4f47a866b984eafb8fb8b653fb3a5eb3137f504fd19", kill_on_drop: false }`
[INFO] [stdout] 37efadb2f601f0eedab9b4f47a866b984eafb8fb8b653fb3a5eb3137f504fd19
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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:d9fbb4e2287ab3795bdefaf705efb7541a8875c13bce71e067d6b01dc5ed759b" "/opt/rustwide/cargo-home/bin/cargo" "+8534be72fc3b9c5f2f2dc4e4ee7b651a008e9a3e" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 391fef7f128871b16c047142f3dd0384eb3c0587e9d337e802fb642e658fab78
[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" "391fef7f128871b16c047142f3dd0384eb3c0587e9d337e802fb642e658fab78", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.19
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling syn v1.0.35
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling runtime-attributes v0.3.0-alpha.6 (/opt/rustwide/workdir)
[INFO] [stdout] error: unused extern crate
[INFO] [stdout]  --> src/lib.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | 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:4:45
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![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 `runtime-attributes`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "391fef7f128871b16c047142f3dd0384eb3c0587e9d337e802fb642e658fab78", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "391fef7f128871b16c047142f3dd0384eb3c0587e9d337e802fb642e658fab78", kill_on_drop: false }`
[INFO] [stdout] 391fef7f128871b16c047142f3dd0384eb3c0587e9d337e802fb642e658fab78