[INFO] fetching crate monotron-synth 0.2.0...
[INFO] checking monotron-synth-0.2.0 against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] extracting crate monotron-synth 0.2.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate monotron-synth 0.2.0 on toolchain 45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate monotron-synth 0.2.0
[INFO] finished tweaking crates.io crate monotron-synth 0.2.0
[INFO] tweaked toml for crates.io crate monotron-synth 0.2.0 written to /workspace/builds/worker-2/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded libpulse-sys v1.18.0
[INFO] [stderr]   Downloaded libpulse-binding v2.23.1
[INFO] [stderr]   Downloaded num-derive v0.3.3
[INFO] [stderr]   Downloaded libpulse-simple-binding v2.23.0
[INFO] [stderr]   Downloaded libpulse-simple-sys v1.16.1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "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] 039306a31995bba60bb257074cbf64fb1e53e7b5e0277fa51921928bdb21b78b
[INFO] running `Command { std: "docker" "start" "-a" "039306a31995bba60bb257074cbf64fb1e53e7b5e0277fa51921928bdb21b78b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "039306a31995bba60bb257074cbf64fb1e53e7b5e0277fa51921928bdb21b78b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "039306a31995bba60bb257074cbf64fb1e53e7b5e0277fa51921928bdb21b78b", kill_on_drop: false }`
[INFO] [stdout] 039306a31995bba60bb257074cbf64fb1e53e7b5e0277fa51921928bdb21b78b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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:c46a2d1a26fb48b37929c74ca49dd9409f2375a0a3bdb8fe07617f3ffccaa889" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5a865bcf31c7fc6e1a33226c8cd4924ae51ea7160e05211b68f5d97a8d8c211d
[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" "5a865bcf31c7fc6e1a33226c8cd4924ae51ea7160e05211b68f5d97a8d8c211d", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling pkg-config v0.3.19
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling syn v1.0.69
[INFO] [stderr]    Compiling libc v0.2.93
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking monotron-synth v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:359:9
[INFO] [stdout]     |
[INFO] [stdout] 359 |         (intermediate as u8)
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling libpulse-sys v1.18.0
[INFO] [stderr]    Compiling libpulse-simple-sys v1.16.1
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]    Compiling num-derive v0.3.3
[INFO] [stderr]     Checking libpulse-binding v2.23.1
[INFO] [stderr]     Checking libpulse-simple-binding v2.23.0
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:359:9
[INFO] [stdout]     |
[INFO] [stdout] 359 |         (intermediate as u8)
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_parens)]` 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 22.69s
[INFO] running `Command { std: "docker" "inspect" "5a865bcf31c7fc6e1a33226c8cd4924ae51ea7160e05211b68f5d97a8d8c211d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5a865bcf31c7fc6e1a33226c8cd4924ae51ea7160e05211b68f5d97a8d8c211d", kill_on_drop: false }`
[INFO] [stdout] 5a865bcf31c7fc6e1a33226c8cd4924ae51ea7160e05211b68f5d97a8d8c211d