[INFO] fetching crate flowclib 0.8.8...
[INFO] checking flowclib-0.8.8 against try#9c1dcf141bc0875407c4eb36972857bd3db713e2 for pr-81863
[INFO] extracting crate flowclib 0.8.8 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate flowclib 0.8.8 on toolchain 9c1dcf141bc0875407c4eb36972857bd3db713e2
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate flowclib 0.8.8
[INFO] finished tweaking crates.io crate flowclib 0.8.8
[INFO] tweaked toml for crates.io crate flowclib 0.8.8 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] be80a8e096b5e12d1b943f81b674df9d8561c18b7a81e33308666472865be040
[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" "be80a8e096b5e12d1b943f81b674df9d8561c18b7a81e33308666472865be040", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "be80a8e096b5e12d1b943f81b674df9d8561c18b7a81e33308666472865be040", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "be80a8e096b5e12d1b943f81b674df9d8561c18b7a81e33308666472865be040", kill_on_drop: false }`
[INFO] [stdout] be80a8e096b5e12d1b943f81b674df9d8561c18b7a81e33308666472865be040
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+9c1dcf141bc0875407c4eb36972857bd3db713e2" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7e558fbf3bcf44b9e7ff673c5778e3d420c0035f80f3174d5e18561943f17e4f
[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" "7e558fbf3bcf44b9e7ff673c5778e3d420c0035f80f3174d5e18561943f17e4f", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]     Checking linked-hash-map v0.5.4
[INFO] [stderr]     Checking dtoa v0.4.7
[INFO] [stderr]     Checking remove_dir_all v0.5.3
[INFO] [stderr]     Checking strfmt v0.1.6
[INFO] [stderr]    Compiling itertools v0.8.2
[INFO] [stderr]     Checking erased-serde v0.3.13
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]     Checking rand v0.4.6
[INFO] [stderr]     Checking url v2.1.1
[INFO] [stderr]     Checking yaml-rust v0.4.5
[INFO] [stderr]     Checking serde_yaml v0.8.16
[INFO] [stderr]     Checking tempdir v0.3.7
[INFO] [stderr]    Compiling time-macros-impl v0.1.1
[INFO] [stderr]    Compiling serde_derive v1.0.123
[INFO] [stderr]    Compiling shrinkwraprs v0.2.3
[INFO] [stderr]     Checking time-macros v0.1.1
[INFO] [stderr]     Checking time v0.2.25
[INFO] [stderr]     Checking instant v0.1.9
[INFO] [stderr]     Checking flowrlib v0.8.8
[INFO] [stderr]     Checking flowclib v0.8.8 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/model/flow.rs:320:9
[INFO] [stdout]     |
[INFO] [stdout] 320 |         replace(&mut self.connections, Some(connections));
[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] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/model/flow.rs:320:9
[INFO] [stdout]     |
[INFO] [stdout] 320 |         replace(&mut self.connections, Some(connections));
[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 54.19s
[INFO] running `Command { std: "docker" "inspect" "7e558fbf3bcf44b9e7ff673c5778e3d420c0035f80f3174d5e18561943f17e4f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e558fbf3bcf44b9e7ff673c5778e3d420c0035f80f3174d5e18561943f17e4f", kill_on_drop: false }`
[INFO] [stdout] 7e558fbf3bcf44b9e7ff673c5778e3d420c0035f80f3174d5e18561943f17e4f