[INFO] fetching crate serde_deser_iter 0.1.0...
[INFO] checking serde_deser_iter-0.1.0 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate serde_deser_iter 0.1.0 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate serde_deser_iter 0.1.0
[INFO] finished tweaking crates.io crate serde_deser_iter 0.1.0
[INFO] tweaked toml for crates.io crate serde_deser_iter 0.1.0 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate serde_deser_iter 0.1.0 on toolchain 4f260f0f20b3133d20cfb50353c0221943af5796
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate serde_deser_iter 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" "+4f260f0f20b3133d20cfb50353c0221943af5796" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2ac7b807b8ffac3ef049ccf80d0e4f720299d0f84c7b8e082c69836b6d235c39
[INFO] running `Command { std: "docker" "start" "-a" "2ac7b807b8ffac3ef049ccf80d0e4f720299d0f84c7b8e082c69836b6d235c39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2ac7b807b8ffac3ef049ccf80d0e4f720299d0f84c7b8e082c69836b6d235c39", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2ac7b807b8ffac3ef049ccf80d0e4f720299d0f84c7b8e082c69836b6d235c39", kill_on_drop: false }`
[INFO] [stdout] 2ac7b807b8ffac3ef049ccf80d0e4f720299d0f84c7b8e082c69836b6d235c39
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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 -Dunmustuse_in_always_ok" "-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f888fbe690fb6215cbeda7959e52ad9aab87f87e6b3177b2af27f7cbb8ab42b8
[INFO] running `Command { std: "docker" "start" "-a" "f888fbe690fb6215cbeda7959e52ad9aab87f87e6b3177b2af27f7cbb8ab42b8", kill_on_drop: false }`
[INFO] [stderr]    Compiling serde v1.0.189
[INFO] [stderr]    Compiling anyhow v1.0.75
[INFO] [stderr]    Compiling serde_json v1.0.107
[INFO] [stderr]    Compiling syn v2.0.38
[INFO] [stderr]    Compiling serde_derive v1.0.189
[INFO] [stderr]     Checking serde_deser_iter v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: this type will no longer be must used: ControlFlow<Infallible, <I as fold::FoldAggregator>::Acc>
[INFO] [stdout]   --> src/deep/fold.rs:40:90
[INFO] [stdout]    |
[INFO] [stdout] 40 |       fn try_fold(acc: Self::Acc, item: Self::Item) -> ControlFlow<Self::Break, Self::Acc> {
[INFO] [stdout]    |  __________________________________________________________________________________________^
[INFO] [stdout] 41 | |         ControlFlow::Continue(I::f(acc, item))
[INFO] [stdout] 42 | |     }
[INFO] [stdout]    | |_____^
[INFO] [stdout]    |
[INFO] [stdout]    = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: ControlFlow<Infallible, <I as fold::FoldAggregator>::Acc>
[INFO] [stdout]   --> src/deep/fold.rs:41:9
[INFO] [stdout]    |
[INFO] [stdout] 41 |         ControlFlow::Continue(I::f(acc, item))
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: this type will no longer be must used: ControlFlow<Infallible, <I as fold::FoldAggregator>::Acc>
[INFO] [stdout]   --> src/deep/fold.rs:45:15
[INFO] [stdout]    |
[INFO] [stdout] 45 |         match f {
[INFO] [stdout]    |               ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `serde_deser_iter` (lib) due to 3 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "f888fbe690fb6215cbeda7959e52ad9aab87f87e6b3177b2af27f7cbb8ab42b8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f888fbe690fb6215cbeda7959e52ad9aab87f87e6b3177b2af27f7cbb8ab42b8", kill_on_drop: false }`
[INFO] [stdout] f888fbe690fb6215cbeda7959e52ad9aab87f87e6b3177b2af27f7cbb8ab42b8