[INFO] cloning repository https://github.com/rustviz/polonius-engine
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rustviz/polonius-engine" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustviz%2Fpolonius-engine", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustviz%2Fpolonius-engine'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 5b8752c8bf7ed7d2202c166a8e03a8a039232a7b
[INFO] checking rustviz/polonius-engine against master#5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f for pr-87248
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frustviz%2Fpolonius-engine" "/workspace/builds/worker-10/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-10/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/rustviz/polonius-engine on toolchain 5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/rustviz/polonius-engine
[INFO] finished tweaking git repo https://github.com/rustviz/polonius-engine
[INFO] tweaked toml for git repo https://github.com/rustviz/polonius-engine written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] crate git repo https://github.com/rustviz/polonius-engine already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6afba5bd01edb6276041d1fd8a5a213a59f730eb0cd9761aa291b2d1b7fc14ae
[INFO] running `Command { std: "docker" "start" "-a" "6afba5bd01edb6276041d1fd8a5a213a59f730eb0cd9761aa291b2d1b7fc14ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6afba5bd01edb6276041d1fd8a5a213a59f730eb0cd9761aa291b2d1b7fc14ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6afba5bd01edb6276041d1fd8a5a213a59f730eb0cd9761aa291b2d1b7fc14ae", kill_on_drop: false }`
[INFO] [stdout] 6afba5bd01edb6276041d1fd8a5a213a59f730eb0cd9761aa291b2d1b7fc14ae
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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" "+5a8a44196b3cf099f8c9b0156bd902eaec0b4e5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 33ebd17b86dc926854c950b34e5bf7553fa727c863f8ed1ce7018f0a42cbe624
[INFO] running `Command { std: "docker" "start" "-a" "33ebd17b86dc926854c950b34e5bf7553fa727c863f8ed1ce7018f0a42cbe624", kill_on_drop: false }`
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking datafrog v2.0.1
[INFO] [stderr]     Checking polonius-engine v0.12.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `potential_errors`
[INFO] [stdout]    --> src/output/mod.rs:139:5
[INFO] [stdout]     |
[INFO] [stdout] 139 |     potential_errors: Option<FxHashSet<T::Loan>>,
[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] [stdout] warning: field is never read: `potential_errors`
[INFO] [stdout]    --> src/output/mod.rs:139:5
[INFO] [stdout]     |
[INFO] [stdout] 139 |     potential_errors: Option<FxHashSet<T::Loan>>,
[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 1.86s
[INFO] running `Command { std: "docker" "inspect" "33ebd17b86dc926854c950b34e5bf7553fa727c863f8ed1ce7018f0a42cbe624", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "33ebd17b86dc926854c950b34e5bf7553fa727c863f8ed1ce7018f0a42cbe624", kill_on_drop: false }`
[INFO] [stdout] 33ebd17b86dc926854c950b34e5bf7553fa727c863f8ed1ce7018f0a42cbe624