[INFO] crate fort 0.3.0 is already in cache
[INFO] checking fort-0.3.0 against master#6250d56355d72264ece721e8d0dc95b16a6824b1 for pr-68350
[INFO] extracting crate fort 0.3.0 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate fort 0.3.0 on toolchain 6250d56355d72264ece721e8d0dc95b16a6824b1
[INFO] running `"/workspace/cargo-home/bin/cargo" "+6250d56355d72264ece721e8d0dc95b16a6824b1" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate fort 0.3.0
[INFO] finished tweaking crates.io crate fort 0.3.0
[INFO] tweaked toml for crates.io crate fort 0.3.0 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate crates.io crate fort 0.3.0 already has a lockfile, it will not be regenerated
[INFO] running `"/workspace/cargo-home/bin/cargo" "+6250d56355d72264ece721e8d0dc95b16a6824b1" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "/opt/rustwide/cargo-home/bin/cargo" "+6250d56355d72264ece721e8d0dc95b16a6824b1" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 5f666be29c8d8c9b4afebf8a2d2ec1c2f2523921921e468f3a1a09c7d75be20c
[INFO] running `"docker" "start" "-a" "5f666be29c8d8c9b4afebf8a2d2ec1c2f2523921921e468f3a1a09c7d75be20c"`
[INFO] [stderr]    Compiling syn v1.0.11
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking proc-macro2 v1.0.6
[INFO] [stderr]     Checking lightproc v0.3.3
[INFO] [stderr]     Checking crossbeam-epoch v0.7.2
[INFO] [stderr]     Checking crossbeam v0.7.3
[INFO] [stderr]     Checking bastion-executor v0.3.0
[INFO] [stderr]     Checking quote v1.0.2
[INFO] [stderr]     Checking fort v0.3.0 (/opt/rustwide/workdir)
[INFO] [stderr] error: unused extern crate
[INFO] [stderr]  --> src/lib.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | extern crate proc_macro;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
[INFO] [stderr]   |
[INFO] [stderr] note: lint level defined here
[INFO] [stderr]  --> src/lib.rs:1:45
[INFO] [stderr]   |
[INFO] [stderr] 1 | #![forbid(unsafe_code, future_incompatible, rust_2018_idioms)]
[INFO] [stderr]   |                                             ^^^^^^^^^^^^^^^^
[INFO] [stderr]   = note: `#[forbid(unused_extern_crates)]` implied by `#[forbid(rust_2018_idioms)]`
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] error: could not compile `fort`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "5f666be29c8d8c9b4afebf8a2d2ec1c2f2523921921e468f3a1a09c7d75be20c"`
[INFO] running `"docker" "rm" "-f" "5f666be29c8d8c9b4afebf8a2d2ec1c2f2523921921e468f3a1a09c7d75be20c"`
[INFO] [stdout] 5f666be29c8d8c9b4afebf8a2d2ec1c2f2523921921e468f3a1a09c7d75be20c