[INFO] fetching crate discard 1.0.4...
[INFO] building discard-1.0.4 against master#d5c88c22807925c189328ef9d923c5d2b11a95b8 for pr-87066-3
[INFO] extracting crate discard 1.0.4 into /workspace/builds/worker-55/source
[INFO] validating manifest of crates.io crate discard 1.0.4 on toolchain d5c88c22807925c189328ef9d923c5d2b11a95b8
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate discard 1.0.4
[INFO] finished tweaking crates.io crate discard 1.0.4
[INFO] tweaked toml for crates.io crate discard 1.0.4 written to /workspace/builds/worker-55/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "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-55/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-55/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0cc6208ca9aa09687f98c7863737962afdf45ba41e89ad58c3d10c944ad1bead
[INFO] running `Command { std: "docker" "start" "-a" "0cc6208ca9aa09687f98c7863737962afdf45ba41e89ad58c3d10c944ad1bead", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0cc6208ca9aa09687f98c7863737962afdf45ba41e89ad58c3d10c944ad1bead", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0cc6208ca9aa09687f98c7863737962afdf45ba41e89ad58c3d10c944ad1bead", kill_on_drop: false }`
[INFO] [stdout] 0cc6208ca9aa09687f98c7863737962afdf45ba41e89ad58c3d10c944ad1bead
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-55/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-55/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] acc0a6609889f79bdbb098f9a95b66d95146ed8b627de4461eb177985fc7fd4b
[INFO] running `Command { std: "docker" "start" "-a" "acc0a6609889f79bdbb098f9a95b66d95146ed8b627de4461eb177985fc7fd4b", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling discard v1.0.4 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.50s
[INFO] running `Command { std: "docker" "inspect" "acc0a6609889f79bdbb098f9a95b66d95146ed8b627de4461eb177985fc7fd4b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "acc0a6609889f79bdbb098f9a95b66d95146ed8b627de4461eb177985fc7fd4b", kill_on_drop: false }`
[INFO] [stdout] acc0a6609889f79bdbb098f9a95b66d95146ed8b627de4461eb177985fc7fd4b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-55/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-55/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+d5c88c22807925c189328ef9d923c5d2b11a95b8" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7e9a5da52d49639e4dd0fcd34e6ea9e0435c16d38a8f8a50dc1b659db2acca7c
[INFO] running `Command { std: "docker" "start" "-a" "7e9a5da52d49639e4dd0fcd34e6ea9e0435c16d38a8f8a50dc1b659db2acca7c", kill_on_drop: false }`
[INFO] [stderr]    Compiling discard v1.0.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `DiscardOnDrop` that must be used
[INFO] [stdout]    --> src/lib.rs:261:9
[INFO] [stdout]     |
[INFO] [stdout] 261 |         DiscardOnDrop::new(Foo::new());
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout]     = note: 
[INFO] [stdout]             The DiscardOnDrop is unused, which causes it to be immediately discarded.
[INFO] [stdout]             You probably don't want that to happen.
[INFO] [stdout]             
[INFO] [stdout]             How to fix this:
[INFO] [stdout]             
[INFO] [stdout]               * Store the DiscardOnDrop in a variable or data structure.
[INFO] [stdout]             
[INFO] [stdout]               * Or use the DiscardOnDrop::leak function which will cause it to not be
[INFO] [stdout]                 discarded (this *will* leak memory!).
[INFO] [stdout]             
[INFO] [stdout]             See the DiscardOnDrop documentation for more details.
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `DiscardOnDrop` that must be used
[INFO] [stdout]    --> src/lib.rs:262:9
[INFO] [stdout]     |
[INFO] [stdout] 262 |         DiscardOnDrop::new(Foo::new());
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: 
[INFO] [stdout]             The DiscardOnDrop is unused, which causes it to be immediately discarded.
[INFO] [stdout]             You probably don't want that to happen.
[INFO] [stdout]             
[INFO] [stdout]             How to fix this:
[INFO] [stdout]             
[INFO] [stdout]               * Store the DiscardOnDrop in a variable or data structure.
[INFO] [stdout]             
[INFO] [stdout]               * Or use the DiscardOnDrop::leak function which will cause it to not be
[INFO] [stdout]                 discarded (this *will* leak memory!).
[INFO] [stdout]             
[INFO] [stdout]             See the DiscardOnDrop documentation for more details.
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished test [unoptimized + debuginfo] target(s) in 0.51s
[INFO] running `Command { std: "docker" "inspect" "7e9a5da52d49639e4dd0fcd34e6ea9e0435c16d38a8f8a50dc1b659db2acca7c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7e9a5da52d49639e4dd0fcd34e6ea9e0435c16d38a8f8a50dc1b659db2acca7c", kill_on_drop: false }`
[INFO] [stdout] 7e9a5da52d49639e4dd0fcd34e6ea9e0435c16d38a8f8a50dc1b659db2acca7c