[INFO] fetching crate preftool 0.2.0...
[INFO] checking preftool-0.2.0 against try#6f8a6450478f69b8510c8976ab6c2a70b3b0e47c for pr-84920
[INFO] extracting crate preftool 0.2.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate preftool 0.2.0 on toolchain 6f8a6450478f69b8510c8976ab6c2a70b3b0e47c
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate preftool 0.2.0
[INFO] finished tweaking crates.io crate preftool 0.2.0
[INFO] tweaked toml for crates.io crate preftool 0.2.0 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b65a3abe04f152eb04a9106913c569120fcf18961162d9e4cfd775b2d204c1cd
[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" "b65a3abe04f152eb04a9106913c569120fcf18961162d9e4cfd775b2d204c1cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b65a3abe04f152eb04a9106913c569120fcf18961162d9e4cfd775b2d204c1cd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b65a3abe04f152eb04a9106913c569120fcf18961162d9e4cfd775b2d204c1cd", kill_on_drop: false }`
[INFO] [stdout] b65a3abe04f152eb04a9106913c569120fcf18961162d9e4cfd775b2d204c1cd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+6f8a6450478f69b8510c8976ab6c2a70b3b0e47c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 407958d469f64d8760577d04c8781719d2c3c6239c80010acdd1b9373ae4effd
[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" "407958d469f64d8760577d04c8781719d2c3c6239c80010acdd1b9373ae4effd", kill_on_drop: false }`
[INFO] [stderr]    Compiling memchr v2.4.0
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling slog v2.7.0
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]    Compiling cc v1.0.67
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]     Checking gimli v0.23.0
[INFO] [stderr]     Checking arc-swap v1.2.0
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stderr]     Checking rustc-demangle v0.1.19
[INFO] [stderr]     Checking object v0.23.0
[INFO] [stderr]    Compiling cargo-husky v1.5.0
[INFO] [stderr]    Compiling error-chain v0.12.4
[INFO] [stderr]    Compiling miniz_oxide v0.4.4
[INFO] [stderr]    Compiling aho-corasick v0.7.18
[INFO] [stderr]     Checking log v0.3.9
[INFO] [stderr]     Checking slog-scope v4.4.0
[INFO] [stderr]     Checking slog-stdlog v3.0.5
[INFO] [stderr]    Compiling backtrace v0.3.58
[INFO] [stderr]    Compiling regex v1.5.4
[INFO] [stderr]     Checking addr2line v0.14.1
[INFO] [stderr]    Compiling caseless v0.2.1
[INFO] [stderr]     Checking preftool v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `std::mem::replace` that must be used
[INFO] [stdout]    --> src/bind.rs:144:5
[INFO] [stdout]     |
[INFO] [stdout] 144 |     std::mem::replace(value, proxy.into());
[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/bind.rs:144:5
[INFO] [stdout]     |
[INFO] [stdout] 144 |     std::mem::replace(value, proxy.into());
[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 28.33s
[INFO] running `Command { std: "docker" "inspect" "407958d469f64d8760577d04c8781719d2c3c6239c80010acdd1b9373ae4effd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "407958d469f64d8760577d04c8781719d2c3c6239c80010acdd1b9373ae4effd", kill_on_drop: false }`
[INFO] [stdout] 407958d469f64d8760577d04c8781719d2c3c6239c80010acdd1b9373ae4effd