[INFO] crate json_derive 0.0.1-alpha1 is already in cache
[INFO] checking json_derive-0.0.1-alpha1 against master#7c59a81a5fcbaaca311f744cd7c68d99bfbb05d3 for pr-71873
[INFO] extracting crate json_derive 0.0.1-alpha1 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate json_derive 0.0.1-alpha1 on toolchain 7c59a81a5fcbaaca311f744cd7c68d99bfbb05d3
[INFO] running `"/workspace/cargo-home/bin/cargo" "+7c59a81a5fcbaaca311f744cd7c68d99bfbb05d3" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate json_derive 0.0.1-alpha1
[INFO] finished tweaking crates.io crate json_derive 0.0.1-alpha1
[INFO] tweaked toml for crates.io crate json_derive 0.0.1-alpha1 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+7c59a81a5fcbaaca311f744cd7c68d99bfbb05d3" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+7c59a81a5fcbaaca311f744cd7c68d99bfbb05d3" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "+7c59a81a5fcbaaca311f744cd7c68d99bfbb05d3" "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] b605448a9cd06a36e1d842e2a7fe90b8dfd2c921de50875a6fd2ea40b6dbe482
[INFO] running `"docker" "start" "-a" "b605448a9cd06a36e1d842e2a7fe90b8dfd2c921de50875a6fd2ea40b6dbe482"`
[INFO] [stderr] sudo: setrlimit(RLIMIT_CORE): Operation not permitted
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling autocfg v1.0.0
[INFO] [stderr]    Compiling syn v0.15.31
[INFO] [stderr]    Compiling indexmap v1.3.2
[INFO] [stderr]     Checking quote v0.6.11
[INFO] [stderr]     Checking serde_json v1.0.39
[INFO] [stderr]     Checking json_derive v0.0.1-alpha1 (/opt/rustwide/workdir)
[INFO] [stderr] warning: unused extern crate
[INFO] [stderr]  --> src/lib.rs:5:1
[INFO] [stderr]   |
[INFO] [stderr] 5 | extern crate proc_macro;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
[INFO] [stderr]   |
[INFO] [stderr] note: the lint level is defined here
[INFO] [stderr]  --> src/lib.rs:3:9
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![warn(unused_extern_crates)]
[INFO] [stderr]   |         ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr] warning: unused extern crate
[INFO] [stderr]  --> src/lib.rs:5:1
[INFO] [stderr]   |
[INFO] [stderr] 5 | extern crate proc_macro;
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove it
[INFO] [stderr]   |
[INFO] [stderr] note: the lint level is defined here
[INFO] [stderr]  --> src/lib.rs:3:9
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![warn(unused_extern_crates)]
[INFO] [stderr]   |         ^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] warning: 1 warning emitted
[INFO] [stderr] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 9.36s
[INFO] running `"docker" "inspect" "b605448a9cd06a36e1d842e2a7fe90b8dfd2c921de50875a6fd2ea40b6dbe482"`
[INFO] running `"docker" "rm" "-f" "b605448a9cd06a36e1d842e2a7fe90b8dfd2c921de50875a6fd2ea40b6dbe482"`
[INFO] [stdout] b605448a9cd06a36e1d842e2a7fe90b8dfd2c921de50875a6fd2ea40b6dbe482