[INFO] fetching crate tracing-allocations 0.1.0...
[INFO] checking tracing-allocations-0.1.0 against master#ab869e094a907cc5d19b4080f22eccaf347f1f95 for pr-129604
[INFO] extracting crate tracing-allocations 0.1.0 into /workspace/builds/worker-4-tc1/source
[INFO] validating manifest of crates.io crate tracing-allocations 0.1.0 on toolchain ab869e094a907cc5d19b4080f22eccaf347f1f95
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate tracing-allocations 0.1.0
[INFO] finished tweaking crates.io crate tracing-allocations 0.1.0
[INFO] tweaked toml for crates.io crate tracing-allocations 0.1.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate crates.io crate tracing-allocations 0.1.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "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-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 1c3132dd7b079f22a492b83c388b936fe3bba95c91bf7880956eea9055ac2c37
[INFO] running `Command { std: "docker" "start" "-a" "1c3132dd7b079f22a492b83c388b936fe3bba95c91bf7880956eea9055ac2c37", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1c3132dd7b079f22a492b83c388b936fe3bba95c91bf7880956eea9055ac2c37", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1c3132dd7b079f22a492b83c388b936fe3bba95c91bf7880956eea9055ac2c37", kill_on_drop: false }`
[INFO] [stdout] 1c3132dd7b079f22a492b83c388b936fe3bba95c91bf7880956eea9055ac2c37
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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" "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@sha256:923055f121b5182466d55868a8b05e67af8ba4a3a3f6bad814e953ca3cd3ac2a" "/opt/rustwide/cargo-home/bin/cargo" "+ab869e094a907cc5d19b4080f22eccaf347f1f95" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 960b630122f8c697f7fee387a309e1cff086873a23e304289551d0cd42cd50c5
[INFO] running `Command { std: "docker" "start" "-a" "960b630122f8c697f7fee387a309e1cff086873a23e304289551d0cd42cd50c5", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.119
[INFO] [stderr]    Compiling syn v1.0.86
[INFO] [stderr]    Compiling parking_lot_core v0.9.1
[INFO] [stderr]     Checking once_cell v1.10.0
[INFO] [stderr]     Checking tracing-core v0.1.22
[INFO] [stderr]     Checking lock_api v0.4.6
[INFO] [stderr]     Checking sharded-slab v0.1.4
[INFO] [stderr]     Checking thread_local v1.1.4
[INFO] [stderr]     Checking tracing-log v0.1.2
[INFO] [stderr]     Checking tracing-subscriber v0.3.9
[INFO] [stderr]     Checking signal-hook-registry v1.4.0
[INFO] [stderr]     Checking num_cpus v1.13.1
[INFO] [stderr]     Checking socket2 v0.4.4
[INFO] [stderr]     Checking mio v0.8.0
[INFO] [stderr]     Checking parking_lot v0.12.0
[INFO] [stderr]    Compiling tracing-attributes v0.1.19
[INFO] [stderr]    Compiling tokio-macros v1.7.0
[INFO] [stderr]     Checking tokio v1.17.0
[INFO] [stderr]     Checking tracing v0.1.31
[INFO] [stderr]     Checking tracing-allocations v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: calls to `std::mem::drop` with a reference instead of an owned value does nothing
[INFO] [stdout]   --> src/lib.rs:84:17
[INFO] [stdout]    |
[INFO] [stdout] 84 |                 drop(guard);
[INFO] [stdout]    |                 ^^^^^-----^
[INFO] [stdout]    |                      |
[INFO] [stdout]    |                      argument has type `&RefCell<bool>`
[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] 84 -                 drop(guard);
[INFO] [stdout] 84 +                 let _ = guard;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Instrument` and `trace_span`
[INFO] [stdout]  --> examples/simple.rs:1:15
[INFO] [stdout]   |
[INFO] [stdout] 1 | use tracing::{trace_span, Instrument};
[INFO] [stdout]   |               ^^^^^^^^^^  ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[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/lib.rs:84:17
[INFO] [stdout]    |
[INFO] [stdout] 84 |                 drop(guard);
[INFO] [stdout]    |                 ^^^^^-----^
[INFO] [stdout]    |                      |
[INFO] [stdout]    |                      argument has type `&RefCell<bool>`
[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] 84 -                 drop(guard);
[INFO] [stdout] 84 +                 let _ = guard;
[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 12.69s
[INFO] running `Command { std: "docker" "inspect" "960b630122f8c697f7fee387a309e1cff086873a23e304289551d0cd42cd50c5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "960b630122f8c697f7fee387a309e1cff086873a23e304289551d0cd42cd50c5", kill_on_drop: false }`
[INFO] [stdout] 960b630122f8c697f7fee387a309e1cff086873a23e304289551d0cd42cd50c5