[INFO] fetching crate optional_struct 0.2.0...
[INFO] checking optional_struct-0.2.0 against master#4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5 for pr-81174
[INFO] extracting crate optional_struct 0.2.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate optional_struct 0.2.0 on toolchain 4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate optional_struct 0.2.0
[INFO] finished tweaking crates.io crate optional_struct 0.2.0
[INFO] tweaked toml for crates.io crate optional_struct 0.2.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "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" "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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "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] 1569f1d867583cd4495032878fa17546e0ed1a9d65ee2f73aa18792a7b26c043
[INFO] running `Command { std: "docker" "start" "-a" "1569f1d867583cd4495032878fa17546e0ed1a9d65ee2f73aa18792a7b26c043", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1569f1d867583cd4495032878fa17546e0ed1a9d65ee2f73aa18792a7b26c043", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1569f1d867583cd4495032878fa17546e0ed1a9d65ee2f73aa18792a7b26c043", kill_on_drop: false }`
[INFO] [stdout] 1569f1d867583cd4495032878fa17546e0ed1a9d65ee2f73aa18792a7b26c043
[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" "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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 7bec53a124f1f2028fcd450ee14448c2410199bf74f1ca316d9d273df90e33db
[INFO] running `Command { std: "docker" "start" "-a" "7bec53a124f1f2028fcd450ee14448c2410199bf74f1ca316d9d273df90e33db", kill_on_drop: false }`
[INFO] [stderr]     Checking unicode-xid v0.0.4
[INFO] [stderr]     Checking quote v0.3.15
[INFO] [stderr]    Compiling synom v0.11.3
[INFO] [stderr]    Compiling syn v0.11.11
[INFO] [stderr]     Checking optional_struct v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: struct is never constructed: `Config`
[INFO] [stdout]  --> tests/empty.rs:5:8
[INFO] [stdout]   |
[INFO] [stdout] 5 | struct Config {
[INFO] [stdout]   |        ^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 7.87s
[INFO] running `Command { std: "docker" "inspect" "7bec53a124f1f2028fcd450ee14448c2410199bf74f1ca316d9d273df90e33db", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7bec53a124f1f2028fcd450ee14448c2410199bf74f1ca316d9d273df90e33db", kill_on_drop: false }`
[INFO] [stdout] 7bec53a124f1f2028fcd450ee14448c2410199bf74f1ca316d9d273df90e33db