[INFO] fetching crate pyo3-python-tracing-subscriber 0.1.0...
[INFO] checking pyo3-python-tracing-subscriber-0.1.0 against try#4f260f0f20b3133d20cfb50353c0221943af5796+rustflags=-Dunmustuse_in_always_ok for pr-148577
[INFO] extracting crate pyo3-python-tracing-subscriber 0.1.0 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate pyo3-python-tracing-subscriber 0.1.0
[INFO] finished tweaking crates.io crate pyo3-python-tracing-subscriber 0.1.0
[INFO] tweaked toml for crates.io crate pyo3-python-tracing-subscriber 0.1.0 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate pyo3-python-tracing-subscriber 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] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4f260f0f20b3133d20cfb50353c0221943af5796" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 43 packages to latest compatible versions
[INFO] [stderr]       Adding pyo3 v0.22.6 (available: v0.27.1)
[INFO] [stderr]       Adding tracing-serde v0.1.3 (available: v0.2.0)
[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-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 6545dc63a8b1f255cf64c5a67c0ffc6033a8b288633a5e27ba0e948418852844
[INFO] running `Command { std: "docker" "start" "-a" "6545dc63a8b1f255cf64c5a67c0ffc6033a8b288633a5e27ba0e948418852844", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6545dc63a8b1f255cf64c5a67c0ffc6033a8b288633a5e27ba0e948418852844", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6545dc63a8b1f255cf64c5a67c0ffc6033a8b288633a5e27ba0e948418852844", kill_on_drop: false }`
[INFO] [stdout] 6545dc63a8b1f255cf64c5a67c0ffc6033a8b288633a5e27ba0e948418852844
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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] 1fdc3a10584d76c5b5fbbbec7a6b2a71d82554647bdba6c65e2482ceee5d6b47
[INFO] running `Command { std: "docker" "start" "-a" "1fdc3a10584d76c5b5fbbbec7a6b2a71d82554647bdba6c65e2482ceee5d6b47", kill_on_drop: false }`
[INFO] [stderr]    Compiling target-lexicon v0.12.16
[INFO] [stderr]    Compiling indoc v2.0.7
[INFO] [stderr]     Checking unindent v0.2.4
[INFO] [stderr]     Checking tracing-subscriber v0.3.20
[INFO] [stderr]     Checking tracing-serde v0.1.3
[INFO] [stderr]    Compiling pyo3-build-config v0.22.6
[INFO] [stderr]    Compiling pyo3-ffi v0.22.6
[INFO] [stderr]    Compiling pyo3-macros-backend v0.22.6
[INFO] [stderr]    Compiling pyo3 v0.22.6
[INFO] [stderr]    Compiling pyo3-macros v0.22.6
[INFO] [stderr]     Checking pyo3-python-tracing-subscriber v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error: this type will no longer be must used: Result<u16, Infallible>
[INFO] [stdout]    --> src/lib.rs:184:80
[INFO] [stdout]     |
[INFO] [stdout] 184 |         pub fn on_new_span(&mut self, span_attrs: String, _span_id: String) -> u16 {
[INFO] [stdout]     |                                                                                ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: requested on the command line with `-D unmustuse-in-always-ok`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `pyo3-python-tracing-subscriber` (lib test) due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "1fdc3a10584d76c5b5fbbbec7a6b2a71d82554647bdba6c65e2482ceee5d6b47", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1fdc3a10584d76c5b5fbbbec7a6b2a71d82554647bdba6c65e2482ceee5d6b47", kill_on_drop: false }`
[INFO] [stdout] 1fdc3a10584d76c5b5fbbbec7a6b2a71d82554647bdba6c65e2482ceee5d6b47