[INFO] fetching crate index-ext 0.0.2...
[INFO] checking index-ext-0.0.2 against master#6526e5c772f2da07db745c94ca6bb0a591a39ba4 for pr-80920
[INFO] extracting crate index-ext 0.0.2 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate index-ext 0.0.2 on toolchain 6526e5c772f2da07db745c94ca6bb0a591a39ba4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate index-ext 0.0.2
[INFO] removed 0 missing examples
[INFO] finished tweaking crates.io crate index-ext 0.0.2
[INFO] tweaked toml for crates.io crate index-ext 0.0.2 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate crates.io crate index-ext 0.0.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "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] ee08c5da3d4cc1952426ee35ed8be879c090f1accf9014c2834221b318849cd0
[INFO] running `Command { std: "docker" "start" "-a" "ee08c5da3d4cc1952426ee35ed8be879c090f1accf9014c2834221b318849cd0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "ee08c5da3d4cc1952426ee35ed8be879c090f1accf9014c2834221b318849cd0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ee08c5da3d4cc1952426ee35ed8be879c090f1accf9014c2834221b318849cd0", kill_on_drop: false }`
[INFO] [stdout] ee08c5da3d4cc1952426ee35ed8be879c090f1accf9014c2834221b318849cd0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "+6526e5c772f2da07db745c94ca6bb0a591a39ba4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 646f4b843a05e716f21d893c8e33659a555da86928ecd5990fd275b55932fae3
[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" "646f4b843a05e716f21d893c8e33659a555da86928ecd5990fd275b55932fae3", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.77
[INFO] [stderr]     Checking index-ext v0.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `ManuallyDrop::<T>::new` that must be used
[INFO] [stdout]    --> src/tag.rs:474:9
[INFO] [stdout]     |
[INFO] [stdout] 474 |         core::mem::ManuallyDrop::new(t);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the wrapper, you can use `mem::forget` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary trailing semicolon
[INFO] [stdout]    --> src/lib.rs:378:10
[INFO] [stdout]     |
[INFO] [stdout] 378 |         };
[INFO] [stdout]     |          ^ help: remove this semicolon
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(redundant_semicolons)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `ManuallyDrop::<T>::new` that must be used
[INFO] [stdout]    --> src/tag.rs:474:9
[INFO] [stdout]     |
[INFO] [stdout] 474 |         core::mem::ManuallyDrop::new(t);
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: if you don't need the wrapper, you can use `mem::forget` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 3.70s
[INFO] running `Command { std: "docker" "inspect" "646f4b843a05e716f21d893c8e33659a555da86928ecd5990fd275b55932fae3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "646f4b843a05e716f21d893c8e33659a555da86928ecd5990fd275b55932fae3", kill_on_drop: false }`
[INFO] [stdout] 646f4b843a05e716f21d893c8e33659a555da86928ecd5990fd275b55932fae3