[INFO] fetching crate preftool 0.2.0...
[INFO] checking preftool-0.2.0 against try#7014e13d5becc920d4bea3cd87942c8a13d359bf+rustflags=-Dtail_expr_drop_order for pr-129864
[INFO] extracting crate preftool 0.2.0 into /workspace/builds/worker-0-tc2/source
[INFO] validating manifest of crates.io crate preftool 0.2.0 on toolchain 7014e13d5becc920d4bea3cd87942c8a13d359bf
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "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-0-tc2/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]      Locking 38 packages to latest compatible versions
[INFO] [stderr]       Adding crossbeam v0.2.12 (available: v0.8.4)
[INFO] [stderr]       Adding log v0.3.9 (available: v0.4.22)
[INFO] [stderr]       Adding slog-stdlog v3.0.5 (available: v4.1.1)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "fetch" "--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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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:ceb6ea022f8a89cebbe621bb4987e73a935bd40dfbb726f832cfff4742a5b95a" "/opt/rustwide/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 42c0a0ca7e5e7a820c8103788a5301f7a3f196d6fc2f6437f2efb727550c2f58
[INFO] running `Command { std: "docker" "start" "-a" "42c0a0ca7e5e7a820c8103788a5301f7a3f196d6fc2f6437f2efb727550c2f58", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "42c0a0ca7e5e7a820c8103788a5301f7a3f196d6fc2f6437f2efb727550c2f58", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "42c0a0ca7e5e7a820c8103788a5301f7a3f196d6fc2f6437f2efb727550c2f58", kill_on_drop: false }`
[INFO] [stdout] 42c0a0ca7e5e7a820c8103788a5301f7a3f196d6fc2f6437f2efb727550c2f58
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/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 -Dtail_expr_drop_order" "-e" "RUSTDOCFLAGS=--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:ceb6ea022f8a89cebbe621bb4987e73a935bd40dfbb726f832cfff4742a5b95a" "/opt/rustwide/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7963e61e08a5cb032cfdb9f83f98399b83bb2e328dc05c10904507628c4d5c41
[INFO] running `Command { std: "docker" "start" "-a" "7963e61e08a5cb032cfdb9f83f98399b83bb2e328dc05c10904507628c4d5c41", kill_on_drop: false }`
[INFO] [stderr]    Compiling slog v2.7.0
[INFO] [stderr]    Compiling libc v0.2.159
[INFO] [stderr]     Checking arc-swap v1.7.1
[INFO] [stderr]     Checking crossbeam v0.2.12
[INFO] [stderr]    Compiling cargo-husky v1.5.0
[INFO] [stderr]     Checking miniz_oxide v0.8.0
[INFO] [stderr]    Compiling error-chain v0.12.4
[INFO] [stderr]     Checking log v0.3.9
[INFO] [stderr]    Compiling caseless v0.2.1
[INFO] [stderr]     Checking slog-scope v4.4.0
[INFO] [stderr]     Checking slog-stdlog v3.0.5
[INFO] [stderr]     Checking backtrace v0.3.74
[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: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 144 |     let _ = std::mem::replace(value, proxy.into());
[INFO] [stdout]     |     +++++++
[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: if you don't need the old value, you can just assign the new value directly
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]     |
[INFO] [stdout] 144 |     let _ = std::mem::replace(value, proxy.into());
[INFO] [stdout]     |     +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.70s
[INFO] running `Command { std: "docker" "inspect" "7963e61e08a5cb032cfdb9f83f98399b83bb2e328dc05c10904507628c4d5c41", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7963e61e08a5cb032cfdb9f83f98399b83bb2e328dc05c10904507628c4d5c41", kill_on_drop: false }`
[INFO] [stdout] 7963e61e08a5cb032cfdb9f83f98399b83bb2e328dc05c10904507628c4d5c41