[INFO] fetching crate blc 0.6.0...
[INFO] checking blc-0.6.0 against try#b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f for pr-76104
[INFO] extracting crate blc 0.6.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate blc 0.6.0 on toolchain b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate blc 0.6.0
[INFO] finished tweaking crates.io crate blc 0.6.0
[INFO] tweaked toml for crates.io crate blc 0.6.0 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded lambda_calculus v2.2.0
[INFO] running `Command { std: "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" "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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e147dfab79feb6d1871fb5fee4558a4f4017a8df276caac6341cde64a0507378
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "e147dfab79feb6d1871fb5fee4558a4f4017a8df276caac6341cde64a0507378", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e147dfab79feb6d1871fb5fee4558a4f4017a8df276caac6341cde64a0507378", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e147dfab79feb6d1871fb5fee4558a4f4017a8df276caac6341cde64a0507378", kill_on_drop: false }`
[INFO] [stdout] e147dfab79feb6d1871fb5fee4558a4f4017a8df276caac6341cde64a0507378
[INFO] running `Command { std: "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" "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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+b1cc2963e8346ba1f5afb1edb86dbcf3f9ef0c5f" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e6f1b224b628853e2b9743152e19cb79ecc3cc9728978d32ae137572230aca42
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "e6f1b224b628853e2b9743152e19cb79ecc3cc9728978d32ae137572230aca42", kill_on_drop: false }`
[INFO] [stderr]     Checking lambda_calculus v2.2.0
[INFO] [stderr]     Checking blc v0.6.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]   --> src/lib.rs:42:1
[INFO] [stdout]    |
[INFO] [stdout] 42 | #[macro_use]
[INFO] [stdout]    | ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/pair_list.rs:112:5
[INFO] [stdout]     |
[INFO] [stdout] 112 |     mem::replace(term, tail.clone()); // replace term with tail
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/pair_list.rs:112:5
[INFO] [stdout]     |
[INFO] [stdout] 112 |     mem::replace(term, tail.clone()); // replace term with tail
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.93s
[INFO] running `Command { std: "docker" "inspect" "e6f1b224b628853e2b9743152e19cb79ecc3cc9728978d32ae137572230aca42", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e6f1b224b628853e2b9743152e19cb79ecc3cc9728978d32ae137572230aca42", kill_on_drop: false }`
[INFO] [stdout] e6f1b224b628853e2b9743152e19cb79ecc3cc9728978d32ae137572230aca42