[INFO] fetching crate untyped-arena 0.1.1...
[INFO] checking untyped-arena-0.1.1 against master#cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c for pr-143170
[INFO] extracting crate untyped-arena 0.1.1 into /workspace/builds/worker-0-tc1/source
[INFO] started tweaking crates.io crate untyped-arena 0.1.1
[INFO] finished tweaking crates.io crate untyped-arena 0.1.1
[INFO] tweaked toml for crates.io crate untyped-arena 0.1.1 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate untyped-arena 0.1.1 on toolchain cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate untyped-arena 0.1.1 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" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[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-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5276c090ff55b24f19e824fb962f6985fff1befbb66bbb71d0607e78f07b9819
[INFO] running `Command { std: "docker" "start" "-a" "5276c090ff55b24f19e824fb962f6985fff1befbb66bbb71d0607e78f07b9819", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5276c090ff55b24f19e824fb962f6985fff1befbb66bbb71d0607e78f07b9819", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5276c090ff55b24f19e824fb962f6985fff1befbb66bbb71d0607e78f07b9819", kill_on_drop: false }`
[INFO] [stdout] 5276c090ff55b24f19e824fb962f6985fff1befbb66bbb71d0607e78f07b9819
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+cf38b8e663f15db10ce49d7bbce02c99fc3dbc0c" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5ef4cf326561e7d521b4eb33a8487d4898483c4458750979f4cca3dc404fccf0
[INFO] running `Command { std: "docker" "start" "-a" "5ef4cf326561e7d521b4eb33a8487d4898483c4458750979f4cca3dc404fccf0", kill_on_drop: false }`
[INFO] [stderr]     Checking untyped-arena v0.1.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> examples/dropck_tests.rs:29:9
[INFO] [stdout]    |
[INFO] [stdout] 29 |     let mut a = arena.alloc(A::default());
[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]   --> examples/dropck_tests.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |     let mut b = arena.alloc(A::default());
[INFO] [stdout]    |         ----^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0597]: `arena` does not live long enough
[INFO] [stdout]   --> examples/dropck_tests.rs:29:17
[INFO] [stdout]    |
[INFO] [stdout] 28 |     let arena = Arena::new();
[INFO] [stdout]    |         ----- binding `arena` declared here
[INFO] [stdout] 29 |     let mut a = arena.alloc(A::default());
[INFO] [stdout]    |                 ^^^^^ borrowed value does not live long enough
[INFO] [stdout] ...
[INFO] [stdout] 32 | }
[INFO] [stdout]    | -
[INFO] [stdout]    | |
[INFO] [stdout]    | `arena` dropped here while still borrowed
[INFO] [stdout]    | borrow might be used here, when `arena` is dropped and runs the `Drop` code for type `Arena`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0597`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `untyped-arena` (example "dropck_tests") due to 1 previous error; 2 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "5ef4cf326561e7d521b4eb33a8487d4898483c4458750979f4cca3dc404fccf0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5ef4cf326561e7d521b4eb33a8487d4898483c4458750979f4cca3dc404fccf0", kill_on_drop: false }`
[INFO] [stdout] 5ef4cf326561e7d521b4eb33a8487d4898483c4458750979f4cca3dc404fccf0