[INFO] fetching crate ur20-modbus 0.4.0...
[INFO] checking ur20-modbus-0.4.0 against try#590af02d982816cfb2e4e43f8c54065e816581ce for pr-111505
[INFO] extracting crate ur20-modbus 0.4.0 into /workspace/builds/worker-2-tc2/source
[INFO] validating manifest of crates.io crate ur20-modbus 0.4.0 on toolchain 590af02d982816cfb2e4e43f8c54065e816581ce
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+590af02d982816cfb2e4e43f8c54065e816581ce" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate ur20-modbus 0.4.0
[INFO] finished tweaking crates.io crate ur20-modbus 0.4.0
[INFO] tweaked toml for crates.io crate ur20-modbus 0.4.0 written to /workspace/builds/worker-2-tc2/source/Cargo.toml
[INFO] crate crates.io crate ur20-modbus 0.4.0 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" "+590af02d982816cfb2e4e43f8c54065e816581ce" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+590af02d982816cfb2e4e43f8c54065e816581ce" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 40428e5ab6e4a7bf426f08b5e433213ce82812083f8238abe76c311e27836181
[INFO] running `Command { std: "docker" "start" "-a" "40428e5ab6e4a7bf426f08b5e433213ce82812083f8238abe76c311e27836181", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "40428e5ab6e4a7bf426f08b5e433213ce82812083f8238abe76c311e27836181", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "40428e5ab6e4a7bf426f08b5e433213ce82812083f8238abe76c311e27836181", kill_on_drop: false }`
[INFO] [stdout] 40428e5ab6e4a7bf426f08b5e433213ce82812083f8238abe76c311e27836181
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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@sha256:19e73879b68f455e41552ea35293514db52ea292d993f571636dbffedb77a1ee" "/opt/rustwide/cargo-home/bin/cargo" "+590af02d982816cfb2e4e43f8c54065e816581ce" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c2711b77ff88f402172b7c19556717cf79db5ef77d5444b421c6f8e2af843334
[INFO] running `Command { std: "docker" "start" "-a" "c2711b77ff88f402172b7c19556717cf79db5ef77d5444b421c6f8e2af843334", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.67
[INFO] [stderr]    Compiling proc-macro2 v1.0.9
[INFO] [stderr]    Compiling syn v1.0.16
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]     Checking arc-swap v0.4.4
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling num-traits v0.2.11
[INFO] [stderr]    Compiling num-derive v0.2.5
[INFO] [stderr]     Checking smallvec v1.2.0
[INFO] [stderr]     Checking futures-util v0.3.4
[INFO] [stderr]    Compiling quote v1.0.3
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]     Checking net2 v0.2.33
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking signal-hook-registry v1.2.0
[INFO] [stderr]     Checking num_cpus v1.12.0
[INFO] [stderr]     Checking mio v0.6.21
[INFO] [stderr]     Checking mio-uds v0.6.7
[INFO] [stderr]    Compiling tokio-macros v0.2.5
[INFO] [stderr]     Checking ur20 v0.5.1
[INFO] [stderr]     Checking tokio v0.2.13
[INFO] [stdout] error: this attribute can only be applied to a `use` item
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/tokio-0.2.13/src/macros/cfg.rs:157:19
[INFO] [stdout]     |
[INFO] [stdout] 157 |               #[doc(inline)]
[INFO] [stdout]     |                     ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]    ::: /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/tokio-0.2.13/src/macros/mod.rs:22:1
[INFO] [stdout]     |
[INFO] [stdout] 22  | / cfg_macros! {
[INFO] [stdout] 23  | |     #[macro_use]
[INFO] [stdout] 24  | |     mod select;
[INFO] [stdout] 25  | |
[INFO] [stdout] ...   |
[INFO] [stdout] 30  | |     mod try_join;
[INFO] [stdout] 31  | | }
[INFO] [stdout]     | |_- in this macro invocation
[INFO] [stdout]     |
[INFO] [stdout]     = note: read <https://doc.rust-lang.org/nightly/rustdoc/the-doc-attribute.html#inline-and-no_inline> for more information
[INFO] [stdout]     = note: this error originates in the macro `cfg_macros` (in Nightly builds, run with -Z macro-backtrace for more info)
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `tokio` (lib) due to 2 previous errors
[INFO] running `Command { std: "docker" "inspect" "c2711b77ff88f402172b7c19556717cf79db5ef77d5444b421c6f8e2af843334", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c2711b77ff88f402172b7c19556717cf79db5ef77d5444b421c6f8e2af843334", kill_on_drop: false }`
[INFO] [stdout] c2711b77ff88f402172b7c19556717cf79db5ef77d5444b421c6f8e2af843334