[INFO] fetching crate tappy 0.1.0...
[INFO] checking tappy-0.1.0 against master#36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923 for pr-81863
[INFO] extracting crate tappy 0.1.0 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate tappy 0.1.0 on toolchain 36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate tappy 0.1.0
[INFO] finished tweaking crates.io crate tappy 0.1.0
[INFO] tweaked toml for crates.io crate tappy 0.1.0 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded parking_lot_core v0.3.1
[INFO] [stderr]   Downloaded crossbeam-utils v0.5.0
[INFO] [stderr]   Downloaded parking_lot v0.6.4
[INFO] [stderr]   Downloaded crossbeam-epoch v0.6.1
[INFO] [stderr]   Downloaded enum-map v0.4.1
[INFO] [stderr]   Downloaded cursive v0.9.2
[INFO] [stderr]   Downloaded enum-map-derive v0.4.6
[INFO] [stderr]   Downloaded crossbeam-channel v0.2.6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b39891667174248f74800ee6f04d9049cc3db3a62cea357ac306456ef6b61037
[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" "b39891667174248f74800ee6f04d9049cc3db3a62cea357ac306456ef6b61037", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b39891667174248f74800ee6f04d9049cc3db3a62cea357ac306456ef6b61037", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b39891667174248f74800ee6f04d9049cc3db3a62cea357ac306456ef6b61037", kill_on_drop: false }`
[INFO] [stdout] b39891667174248f74800ee6f04d9049cc3db3a62cea357ac306456ef6b61037
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f847121ded38ac69c8fd49f5bb6503fd8962ab2d051d5f9d0d30d65f042ec36d
[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" "f847121ded38ac69c8fd49f5bb6503fd8962ab2d051d5f9d0d30d65f042ec36d", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling libc v0.2.85
[INFO] [stderr]    Compiling semver-parser v0.7.0
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]     Checking rand_core v0.4.2
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]    Compiling serde v1.0.123
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking memoffset v0.2.1
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking crossbeam-utils v0.5.0
[INFO] [stderr]     Checking reexport-proc-macro v1.0.6
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]     Checking xi-unicode v0.1.0
[INFO] [stderr]     Checking unicode-segmentation v1.7.1
[INFO] [stderr]     Checking crossbeam-utils v0.6.6
[INFO] [stderr]     Checking rand_core v0.3.1
[INFO] [stderr]    Compiling semver v0.9.0
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling num-rational v0.2.4
[INFO] [stderr]     Checking crossbeam-epoch v0.6.1
[INFO] [stderr]    Compiling rustc_version v0.2.3
[INFO] [stderr]    Compiling quote v0.6.13
[INFO] [stderr]    Compiling parking_lot_core v0.3.1
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling quote v1.0.8
[INFO] [stderr]     Checking rand v0.5.6
[INFO] [stderr]     Checking signal-hook-registry v1.3.0
[INFO] [stderr]     Checking termion v1.5.6
[INFO] [stderr]     Checking signal-hook v0.1.17
[INFO] [stderr]     Checking num v0.2.1
[INFO] [stderr]     Checking parking_lot v0.6.4
[INFO] [stderr]     Checking crossbeam-channel v0.2.6
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]    Compiling enumset_derive v0.3.2
[INFO] [stderr]    Compiling enum-map-derive v0.4.6
[INFO] [stderr]     Checking enumset v0.3.19
[INFO] [stderr]     Checking enum-map v0.4.1
[INFO] [stderr]     Checking cursive v0.9.2
[INFO] [stderr]     Checking tappy v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/main.rs:45:9
[INFO] [stdout]    |
[INFO] [stdout] 45 |         mem::replace(self, Default::default());
[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: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]   --> src/main.rs:45:9
[INFO] [stdout]    |
[INFO] [stdout] 45 |         mem::replace(self, Default::default());
[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: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 45.86s
[INFO] running `Command { std: "docker" "inspect" "f847121ded38ac69c8fd49f5bb6503fd8962ab2d051d5f9d0d30d65f042ec36d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f847121ded38ac69c8fd49f5bb6503fd8962ab2d051d5f9d0d30d65f042ec36d", kill_on_drop: false }`
[INFO] [stdout] f847121ded38ac69c8fd49f5bb6503fd8962ab2d051d5f9d0d30d65f042ec36d