[INFO] fetching crate frankencell 0.2.0...
[INFO] checking frankencell-0.2.0 against try#de0e80659cee4f27282e60d63bbb8c5271a0d147 for pr-129392
[INFO] extracting crate frankencell 0.2.0 into /workspace/builds/worker-7-tc2/source
[INFO] validating manifest of crates.io crate frankencell 0.2.0 on toolchain de0e80659cee4f27282e60d63bbb8c5271a0d147
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+de0e80659cee4f27282e60d63bbb8c5271a0d147" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate frankencell 0.2.0
[INFO] finished tweaking crates.io crate frankencell 0.2.0
[INFO] tweaked toml for crates.io crate frankencell 0.2.0 written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate crates.io crate frankencell 0.2.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+de0e80659cee4f27282e60d63bbb8c5271a0d147" "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-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+de0e80659cee4f27282e60d63bbb8c5271a0d147" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f6cd52ec99c73f0da67d08479083bdec508bf3b36710656a24d9232799139e06
[INFO] running `Command { std: "docker" "start" "-a" "f6cd52ec99c73f0da67d08479083bdec508bf3b36710656a24d9232799139e06", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f6cd52ec99c73f0da67d08479083bdec508bf3b36710656a24d9232799139e06", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f6cd52ec99c73f0da67d08479083bdec508bf3b36710656a24d9232799139e06", kill_on_drop: false }`
[INFO] [stdout] f6cd52ec99c73f0da67d08479083bdec508bf3b36710656a24d9232799139e06
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/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" "RUSTDOCFLAGS=--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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+de0e80659cee4f27282e60d63bbb8c5271a0d147" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 39e08dc9b05dd509899475d7729e6eacb99a0299f9cb1804dafd5f6dbe8fa187
[INFO] running `Command { std: "docker" "start" "-a" "39e08dc9b05dd509899475d7729e6eacb99a0299f9cb1804dafd5f6dbe8fa187", kill_on_drop: false }`
[INFO] [stderr]     Checking frankencell v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> examples/arena.rs:88:5
[INFO] [stdout]    |
[INFO] [stdout] 88 |     drop(b);
[INFO] [stdout]    |     ^^^^^-^
[INFO] [stdout]    |          |
[INFO] [stdout]    |          argument has type `&char`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dropping_references)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 88 -     drop(b);
[INFO] [stdout] 88 +     let _ = b;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> examples/arena.rs:89:5
[INFO] [stdout]    |
[INFO] [stdout] 89 |     drop(a);
[INFO] [stdout]    |     ^^^^^-^
[INFO] [stdout]    |          |
[INFO] [stdout]    |          argument has type `&mut char`
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 89 -     drop(a);
[INFO] [stdout] 89 +     let _ = a;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.29s
[INFO] running `Command { std: "docker" "inspect" "39e08dc9b05dd509899475d7729e6eacb99a0299f9cb1804dafd5f6dbe8fa187", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "39e08dc9b05dd509899475d7729e6eacb99a0299f9cb1804dafd5f6dbe8fa187", kill_on_drop: false }`
[INFO] [stdout] 39e08dc9b05dd509899475d7729e6eacb99a0299f9cb1804dafd5f6dbe8fa187