[INFO] fetching crate im-rc 15.0.0...
[INFO] checking im-rc-15.0.0 against master#5e3f1b148db5bfa27fee52464ae1f5d34c49d77b for pr-75502
[INFO] extracting crate im-rc 15.0.0 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate im-rc 15.0.0 on toolchain 5e3f1b148db5bfa27fee52464ae1f5d34c49d77b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate im-rc 15.0.0
[INFO] finished tweaking crates.io crate im-rc 15.0.0
[INFO] tweaked toml for crates.io crate im-rc 15.0.0 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:e18d859f9e32a1da89bc7b2d7d51e13b57342044d1295d9fc0dd0068c58eb3d1" "/opt/rustwide/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6b901cc64df4898feac091e9c49b02ab1a9417e8e7a44b2ea0518ef031c3f3a3
[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" "6b901cc64df4898feac091e9c49b02ab1a9417e8e7a44b2ea0518ef031c3f3a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6b901cc64df4898feac091e9c49b02ab1a9417e8e7a44b2ea0518ef031c3f3a3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6b901cc64df4898feac091e9c49b02ab1a9417e8e7a44b2ea0518ef031c3f3a3", kill_on_drop: false }`
[INFO] [stdout] 6b901cc64df4898feac091e9c49b02ab1a9417e8e7a44b2ea0518ef031c3f3a3
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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:e18d859f9e32a1da89bc7b2d7d51e13b57342044d1295d9fc0dd0068c58eb3d1" "/opt/rustwide/cargo-home/bin/cargo" "+5e3f1b148db5bfa27fee52464ae1f5d34c49d77b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 9af8ebd47110d8e4e98505b8490eda94871c6a7786404031318a045618c94df4
[INFO] running `Command { std: "docker" "start" "-a" "9af8ebd47110d8e4e98505b8490eda94871c6a7786404031318a045618c94df4", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.76
[INFO] [stderr]    Compiling typenum v1.12.0
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling serde v1.0.115
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]     Checking bit-vec v0.6.2
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking itoa v0.4.6
[INFO] [stderr]     Checking either v1.6.0
[INFO] [stderr]     Checking regex-syntax v0.6.18
[INFO] [stderr]     Checking metrohash v1.0.6
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling im-rc v15.0.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking pretty_assertions v0.6.1
[INFO] [stderr]     Checking crossbeam-utils v0.7.2
[INFO] [stderr]     Checking bit-set v0.5.2
[INFO] [stderr]     Checking crossbeam-epoch v0.8.2
[INFO] [stderr]     Checking crossbeam-channel v0.4.3
[INFO] [stderr]     Checking crossbeam-deque v0.7.3
[INFO] [stderr]     Checking getrandom v0.1.14
[INFO] [stderr]     Checking wait-timeout v0.2.0
[INFO] [stderr]     Checking rand_os v0.1.3
[INFO] [stderr]     Checking num_cpus v1.13.0
[INFO] [stderr]     Checking rayon-core v1.8.0
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr]     Checking rand_chacha v0.2.2
[INFO] [stderr]     Checking rand_pcg v0.2.1
[INFO] [stderr]     Checking rand_xoshiro v0.4.0
[INFO] [stderr]     Checking bitmaps v2.1.0
[INFO] [stderr]     Checking rand v0.7.3
[INFO] [stderr]     Checking rayon v1.4.0
[INFO] [stderr]     Checking tempfile v3.1.0
[INFO] [stderr]     Checking rusty-fork v0.2.2
[INFO] [stderr]     Checking proptest v0.9.6
[INFO] [stderr]     Checking sized-chunks v0.6.2
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]    --> src/lib.rs:341:41
[INFO] [stdout]     |
[INFO] [stdout] 341 | #![cfg_attr(has_specialisation, feature(specialization))]
[INFO] [stdout]     |                                         ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]     = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vector/mod.rs:986:13
[INFO] [stdout]     |
[INFO] [stdout] 986 |             replace(self, other);
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling proptest-derive v0.1.2
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]    --> src/lib.rs:341:41
[INFO] [stdout]     |
[INFO] [stdout] 341 | #![cfg_attr(has_specialisation, feature(specialization))]
[INFO] [stdout]     |                                         ^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]     = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/vector/mod.rs:986:13
[INFO] [stdout]     |
[INFO] [stdout] 986 |             replace(self, other);
[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: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1m 06s
[INFO] running `Command { std: "docker" "inspect" "9af8ebd47110d8e4e98505b8490eda94871c6a7786404031318a045618c94df4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9af8ebd47110d8e4e98505b8490eda94871c6a7786404031318a045618c94df4", kill_on_drop: false }`
[INFO] [stdout] 9af8ebd47110d8e4e98505b8490eda94871c6a7786404031318a045618c94df4