[INFO] fetching crate biheap 0.5.1...
[INFO] checking biheap-0.5.1 against try#7014e13d5becc920d4bea3cd87942c8a13d359bf+rustflags=-Dtail_expr_drop_order for pr-129864
[INFO] extracting crate biheap 0.5.1 into /workspace/builds/worker-2-tc2/source
[INFO] validating manifest of crates.io crate biheap 0.5.1 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 biheap 0.5.1
[INFO] finished tweaking crates.io crate biheap 0.5.1
[INFO] tweaked toml for crates.io crate biheap 0.5.1 written to /workspace/builds/worker-2-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] 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] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 99372e5cd4e616d370cee01ffe30d002000babbd1999ade40d60dda1dd302f5e
[INFO] running `Command { std: "docker" "start" "-a" "99372e5cd4e616d370cee01ffe30d002000babbd1999ade40d60dda1dd302f5e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "99372e5cd4e616d370cee01ffe30d002000babbd1999ade40d60dda1dd302f5e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "99372e5cd4e616d370cee01ffe30d002000babbd1999ade40d60dda1dd302f5e", kill_on_drop: false }`
[INFO] [stdout] 99372e5cd4e616d370cee01ffe30d002000babbd1999ade40d60dda1dd302f5e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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] 9e86583b3bcd6eafe42e2cffbb9ac5c35903560c6d61d2c044313dba8613efbe
[INFO] running `Command { std: "docker" "start" "-a" "9e86583b3bcd6eafe42e2cffbb9ac5c35903560c6d61d2c044313dba8613efbe", kill_on_drop: false }`
[INFO] [stderr]     Checking biheap v0.5.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/core/bubble.rs:124:17
[INFO] [stdout]     |
[INFO] [stdout] 124 |             let mut this = unsafe { &mut *this.get() };
[INFO] [stdout]     |                 ----^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/core/bubble.rs:125:17
[INFO] [stdout]     |
[INFO] [stdout] 125 |             let mut cell = unsafe { &mut *cell_ref.get() }; 
[INFO] [stdout]     |                 ----^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/push.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |         drop(borrow); 
[INFO] [stdout]    |         ^^^^^------^
[INFO] [stdout]    |              |
[INFO] [stdout]    |              argument has type `&mut bivec::BiVec<std::rc::Rc<std::cell::UnsafeCell<core::Node<T>>>>`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dropping_references)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 25 -         drop(borrow); 
[INFO] [stdout] 25 +         let _ = borrow; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/bubble.rs:89:25
[INFO] [stdout]    |
[INFO] [stdout] 89 |                         drop(left_ref); 
[INFO] [stdout]    |                         ^^^^^--------^
[INFO] [stdout]    |                              |
[INFO] [stdout]    |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 89 -                         drop(left_ref); 
[INFO] [stdout] 89 +                         let _ = left_ref; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/bubble.rs:93:25
[INFO] [stdout]    |
[INFO] [stdout] 93 |                         drop(right_ref); 
[INFO] [stdout]    |                         ^^^^^---------^
[INFO] [stdout]    |                              |
[INFO] [stdout]    |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 93 -                         drop(right_ref); 
[INFO] [stdout] 93 +                         let _ = right_ref; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/bubble.rs:99:25
[INFO] [stdout]    |
[INFO] [stdout] 99 |                         drop(left_ref); 
[INFO] [stdout]    |                         ^^^^^--------^
[INFO] [stdout]    |                              |
[INFO] [stdout]    |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 99 -                         drop(left_ref); 
[INFO] [stdout] 99 +                         let _ = left_ref; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]    --> src/core/bubble.rs:103:25
[INFO] [stdout]     |
[INFO] [stdout] 103 |                         drop(right_ref); 
[INFO] [stdout]     |                         ^^^^^---------^
[INFO] [stdout]     |                              |
[INFO] [stdout]     |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]     |
[INFO] [stdout] 103 -                         drop(right_ref); 
[INFO] [stdout] 103 +                         let _ = right_ref; 
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]    --> src/core/peek.rs:117:9
[INFO] [stdout]     |
[INFO] [stdout] 117 |         drop(bivec); 
[INFO] [stdout]     |         ^^^^^-----^
[INFO] [stdout]     |              |
[INFO] [stdout]     |              argument has type `&mut bivec::BiVec<std::rc::Rc<std::cell::UnsafeCell<core::Node<T>>>>`
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]     |
[INFO] [stdout] 117 -         drop(bivec); 
[INFO] [stdout] 117 +         let _ = bivec; 
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/core/bubble.rs:124:17
[INFO] [stdout]     |
[INFO] [stdout] 124 |             let mut this = unsafe { &mut *this.get() };
[INFO] [stdout]     |                 ----^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/core/bubble.rs:125:17
[INFO] [stdout]     |
[INFO] [stdout] 125 |             let mut cell = unsafe { &mut *cell_ref.get() }; 
[INFO] [stdout]     |                 ----^^^^
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/push.rs:25:9
[INFO] [stdout]    |
[INFO] [stdout] 25 |         drop(borrow); 
[INFO] [stdout]    |         ^^^^^------^
[INFO] [stdout]    |              |
[INFO] [stdout]    |              argument has type `&mut bivec::BiVec<std::rc::Rc<std::cell::UnsafeCell<core::Node<T>>>>`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dropping_references)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 25 -         drop(borrow); 
[INFO] [stdout] 25 +         let _ = borrow; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/bubble.rs:89:25
[INFO] [stdout]    |
[INFO] [stdout] 89 |                         drop(left_ref); 
[INFO] [stdout]    |                         ^^^^^--------^
[INFO] [stdout]    |                              |
[INFO] [stdout]    |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 89 -                         drop(left_ref); 
[INFO] [stdout] 89 +                         let _ = left_ref; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/bubble.rs:93:25
[INFO] [stdout]    |
[INFO] [stdout] 93 |                         drop(right_ref); 
[INFO] [stdout]    |                         ^^^^^---------^
[INFO] [stdout]    |                              |
[INFO] [stdout]    |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 93 -                         drop(right_ref); 
[INFO] [stdout] 93 +                         let _ = right_ref; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/core/bubble.rs:99:25
[INFO] [stdout]    |
[INFO] [stdout] 99 |                         drop(left_ref); 
[INFO] [stdout]    |                         ^^^^^--------^
[INFO] [stdout]    |                              |
[INFO] [stdout]    |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]    |
[INFO] [stdout] 99 -                         drop(left_ref); 
[INFO] [stdout] 99 +                         let _ = left_ref; 
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]    --> src/core/bubble.rs:103:25
[INFO] [stdout]     |
[INFO] [stdout] 103 |                         drop(right_ref); 
[INFO] [stdout]     |                         ^^^^^---------^
[INFO] [stdout]     |                              |
[INFO] [stdout]     |                              argument has type `&mut core::Node<T>`
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]     |
[INFO] [stdout] 103 -                         drop(right_ref); 
[INFO] [stdout] 103 +                         let _ = right_ref; 
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]    --> src/core/peek.rs:117:9
[INFO] [stdout]     |
[INFO] [stdout] 117 |         drop(bivec); 
[INFO] [stdout]     |         ^^^^^-----^
[INFO] [stdout]     |              |
[INFO] [stdout]     |              argument has type `&mut bivec::BiVec<std::rc::Rc<std::cell::UnsafeCell<core::Node<T>>>>`
[INFO] [stdout]     |
[INFO] [stdout] help: use `let _ = ...` to ignore the expression or result
[INFO] [stdout]     |
[INFO] [stdout] 117 -         drop(bivec); 
[INFO] [stdout] 117 +         let _ = bivec; 
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.64s
[INFO] running `Command { std: "docker" "inspect" "9e86583b3bcd6eafe42e2cffbb9ac5c35903560c6d61d2c044313dba8613efbe", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9e86583b3bcd6eafe42e2cffbb9ac5c35903560c6d61d2c044313dba8613efbe", kill_on_drop: false }`
[INFO] [stdout] 9e86583b3bcd6eafe42e2cffbb9ac5c35903560c6d61d2c044313dba8613efbe