[INFO] fetching crate optional_struct 0.2.0...
[INFO] checking optional_struct-0.2.0 against try#07fecb9cf34c4979a772ba38c99d6d9144768413 for pr-87710
[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 07fecb9cf34c4979a772ba38c99d6d9144768413
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+07fecb9cf34c4979a772ba38c99d6d9144768413" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", 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" "+07fecb9cf34c4979a772ba38c99d6d9144768413" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+07fecb9cf34c4979a772ba38c99d6d9144768413" "fetch" "--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+07fecb9cf34c4979a772ba38c99d6d9144768413" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e5d6643d716604556179a66448bcc438e928a6c2117f3053f9c03c39921b0a9c
[INFO] running `Command { std: "docker" "start" "-a" "e5d6643d716604556179a66448bcc438e928a6c2117f3053f9c03c39921b0a9c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e5d6643d716604556179a66448bcc438e928a6c2117f3053f9c03c39921b0a9c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e5d6643d716604556179a66448bcc438e928a6c2117f3053f9c03c39921b0a9c", kill_on_drop: false }`
[INFO] [stdout] e5d6643d716604556179a66448bcc438e928a6c2117f3053f9c03c39921b0a9c
[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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+07fecb9cf34c4979a772ba38c99d6d9144768413" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] feb6836fe3d75894676bf35a9fe3176cc0bb5c54a527bbd19ba52d2fb6991725
[INFO] running `Command { std: "docker" "start" "-a" "feb6836fe3d75894676bf35a9fe3176cc0bb5c54a527bbd19ba52d2fb6991725", 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 5.87s
[INFO] running `Command { std: "docker" "inspect" "feb6836fe3d75894676bf35a9fe3176cc0bb5c54a527bbd19ba52d2fb6991725", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "feb6836fe3d75894676bf35a9fe3176cc0bb5c54a527bbd19ba52d2fb6991725", kill_on_drop: false }`
[INFO] [stdout] feb6836fe3d75894676bf35a9fe3176cc0bb5c54a527bbd19ba52d2fb6991725