[INFO] fetching crate walrus-macro 0.18.0...
[INFO] checking walrus-macro-0.18.0 against try#b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b for pr-82781
[INFO] extracting crate walrus-macro 0.18.0 into /workspace/builds/worker-6/source
[INFO] validating manifest of crates.io crate walrus-macro 0.18.0 on toolchain b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate walrus-macro 0.18.0
[INFO] finished tweaking crates.io crate walrus-macro 0.18.0
[INFO] tweaked toml for crates.io crate walrus-macro 0.18.0 written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "fetch" "--locked" "--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-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 23f769cf9f96ee6ee76d931e00a52bd1fd8f4b7af51f7f8a6db9ba435f2f006e
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "23f769cf9f96ee6ee76d931e00a52bd1fd8f4b7af51f7f8a6db9ba435f2f006e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "23f769cf9f96ee6ee76d931e00a52bd1fd8f4b7af51f7f8a6db9ba435f2f006e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "23f769cf9f96ee6ee76d931e00a52bd1fd8f4b7af51f7f8a6db9ba435f2f006e", kill_on_drop: false }`
[INFO] [stdout] 23f769cf9f96ee6ee76d931e00a52bd1fd8f4b7af51f7f8a6db9ba435f2f006e
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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" "rustops/crates-build-env@sha256:f2f6bcd4b43ebee4e173f653a26493129bdb64017c85f916b780ca7fbdbaa79d" "/opt/rustwide/cargo-home/bin/cargo" "+b09a3e9a7a0ff7efb269ec0c13dcc0fd3cedcf6b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 37f3fc9f016035cb7b90885aa22a4e47440964814ee5b2a2acae56918cfc21e8
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "37f3fc9f016035cb7b90885aa22a4e47440964814ee5b2a2acae56918cfc21e8", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.64
[INFO] [stderr]     Checking proc-macro2 v1.0.24
[INFO] [stderr]     Checking heck v0.3.2
[INFO] [stderr]     Checking quote v1.0.9
[INFO] [stderr]     Checking walrus-macro v0.18.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: field is never read: `display_name`
[INFO] [stdout]   --> src/lib.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     display_name: Option<syn::Ident>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `display_extra`
[INFO] [stdout]   --> src/lib.rs:49:5
[INFO] [stdout]    |
[INFO] [stdout] 49 |     display_extra: Option<syn::Ident>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `display_name`
[INFO] [stdout]   --> src/lib.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     display_name: Option<syn::Ident>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field is never read: `display_extra`
[INFO] [stdout]   --> src/lib.rs:49:5
[INFO] [stdout]    |
[INFO] [stdout] 49 |     display_extra: Option<syn::Ident>,
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 6.36s
[INFO] running `Command { std: "docker" "inspect" "37f3fc9f016035cb7b90885aa22a4e47440964814ee5b2a2acae56918cfc21e8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "37f3fc9f016035cb7b90885aa22a4e47440964814ee5b2a2acae56918cfc21e8", kill_on_drop: false }`
[INFO] [stdout] 37f3fc9f016035cb7b90885aa22a4e47440964814ee5b2a2acae56918cfc21e8