[INFO] fetching crate trailing_cell 0.3.0...
[INFO] checking trailing_cell-0.3.0 against try#f47dd4da3ae8c32c9e65d307bfe640b143e674df for pr-77526
[INFO] extracting crate trailing_cell 0.3.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate trailing_cell 0.3.0 on toolchain f47dd4da3ae8c32c9e65d307bfe640b143e674df
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate trailing_cell 0.3.0
[INFO] finished tweaking crates.io crate trailing_cell 0.3.0
[INFO] tweaked toml for crates.io crate trailing_cell 0.3.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded parking_lot_core v0.2.14
[INFO] [stderr]   Downloaded atomic-option v0.1.2
[INFO] [stderr]   Downloaded bus v1.4.1
[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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "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] 3555222ad49a381d0bb2e60798d83fd3871af49f4c08e3edbe6526fbdc02b649
[INFO] running `Command { std: "docker" "start" "-a" "3555222ad49a381d0bb2e60798d83fd3871af49f4c08e3edbe6526fbdc02b649", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3555222ad49a381d0bb2e60798d83fd3871af49f4c08e3edbe6526fbdc02b649", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3555222ad49a381d0bb2e60798d83fd3871af49f4c08e3edbe6526fbdc02b649", kill_on_drop: false }`
[INFO] [stdout] 3555222ad49a381d0bb2e60798d83fd3871af49f4c08e3edbe6526fbdc02b649
[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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 71c20c03af85047cc15cccb140d3e8c6a7e5f0cc59b09fe0b953e221f35a303c
[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" "71c20c03af85047cc15cccb140d3e8c6a7e5f0cc59b09fe0b953e221f35a303c", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.79
[INFO] [stderr]    Compiling maybe-uninit v2.0.0
[INFO] [stderr]     Checking smallvec v0.6.13
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking parking_lot_core v0.2.14
[INFO] [stderr]     Checking bus v1.4.1
[INFO] [stderr]     Checking trailing_cell v0.3.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]   --> src/tests.rs:77:9
[INFO] [stdout]    |
[INFO] [stdout] 77 |         h.join().is_ok();
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]    = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]    --> src/tests.rs:103:5
[INFO] [stdout]     |
[INFO] [stdout] 103 |     h1.join().is_ok();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::result::Result::<T, E>::is_ok` that must be used
[INFO] [stdout]    --> src/tests.rs:104:5
[INFO] [stdout]     |
[INFO] [stdout] 104 |     h2.join().is_ok();
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: if you intended to assert that this is ok, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 5.27s
[INFO] running `Command { std: "docker" "inspect" "71c20c03af85047cc15cccb140d3e8c6a7e5f0cc59b09fe0b953e221f35a303c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "71c20c03af85047cc15cccb140d3e8c6a7e5f0cc59b09fe0b953e221f35a303c", kill_on_drop: false }`
[INFO] [stdout] 71c20c03af85047cc15cccb140d3e8c6a7e5f0cc59b09fe0b953e221f35a303c