[INFO] fetching crate convec 2.0.1...
[INFO] checking convec-2.0.1 against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] extracting crate convec 2.0.1 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate convec 2.0.1 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 convec 2.0.1
[INFO] finished tweaking crates.io crate convec 2.0.1
[INFO] tweaked toml for crates.io crate convec 2.0.1 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] 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] [stdout] 087d8a42c3af460441c3ea4d02323663a0b5943c0ecfe7d2a683ba4f845613bb
[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" "087d8a42c3af460441c3ea4d02323663a0b5943c0ecfe7d2a683ba4f845613bb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "087d8a42c3af460441c3ea4d02323663a0b5943c0ecfe7d2a683ba4f845613bb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "087d8a42c3af460441c3ea4d02323663a0b5943c0ecfe7d2a683ba4f845613bb", kill_on_drop: false }`
[INFO] [stdout] 087d8a42c3af460441c3ea4d02323663a0b5943c0ecfe7d2a683ba4f845613bb
[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] 98e8b30c84d5741ff3ee0bda94be8da604fd31a04f3162515cc2c83af3eb40f7
[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" "98e8b30c84d5741ff3ee0bda94be8da604fd31a04f3162515cc2c83af3eb40f7", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking owning_ref v0.3.3
[INFO] [stderr]     Checking parking_lot_core v0.2.14
[INFO] [stderr]     Checking parking_lot v0.4.8
[INFO] [stderr]     Checking convec v2.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `Option::<T>::is_some` that must be used
[INFO] [stdout]    --> src/lib.rs:176:21
[INFO] [stdout]     |
[INFO] [stdout] 176 |                     stack.pop().is_some();
[INFO] [stdout]     |                     ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you intended to assert that this has a value, consider `.unwrap()` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 2.19s
[INFO] running `Command { std: "docker" "inspect" "98e8b30c84d5741ff3ee0bda94be8da604fd31a04f3162515cc2c83af3eb40f7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "98e8b30c84d5741ff3ee0bda94be8da604fd31a04f3162515cc2c83af3eb40f7", kill_on_drop: false }`
[INFO] [stdout] 98e8b30c84d5741ff3ee0bda94be8da604fd31a04f3162515cc2c83af3eb40f7