[INFO] fetching crate prefect 0.2.0...
[INFO] building prefect-0.2.0 against master#c7f6aa2869acdbf014d094c6e427e554e160b6db for pr-146237-2
[INFO] extracting crate prefect 0.2.0 into /workspace/builds/worker-2-tc1/source
[INFO] started tweaking crates.io crate prefect 0.2.0
[INFO] finished tweaking crates.io crate prefect 0.2.0
[INFO] tweaked toml for crates.io crate prefect 0.2.0 written to /workspace/builds/worker-2-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate prefect 0.2.0 on toolchain c7f6aa2869acdbf014d094c6e427e554e160b6db
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+c7f6aa2869acdbf014d094c6e427e554e160b6db" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate prefect 0.2.0 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" "+c7f6aa2869acdbf014d094c6e427e554e160b6db" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tokio-macros v1.8.2
[INFO] [stderr]   Downloaded thread_local v1.1.4
[INFO] [stderr]   Downloaded rusqlite_migration v1.0.1
[INFO] [stderr]   Downloaded deadpool-sqlite v0.5.0
[INFO] [stderr]   Downloaded owo-colors v3.5.0
[INFO] [stderr]   Downloaded tracing-error v0.2.0
[INFO] [stderr]   Downloaded addr2line v0.17.0
[INFO] [stderr]   Downloaded futures-executor v0.3.25
[INFO] [stderr]   Downloaded ahash v0.8.2
[INFO] [stderr]   Downloaded miniz_oxide v0.5.4
[INFO] [stderr]   Downloaded futures v0.3.25
[INFO] [stderr]   Downloaded backtrace v0.3.66
[INFO] [stderr]   Downloaded hashlink v0.8.1
[INFO] [stderr]   Downloaded eyre v0.6.8
[INFO] [stderr]   Downloaded serde_derive v1.0.148
[INFO] [stderr]   Downloaded tracing-subscriber v0.3.16
[INFO] [stderr]   Downloaded color-spantrace v0.2.0
[INFO] [stderr]   Downloaded deadpool v0.9.5
[INFO] [stderr]   Downloaded ulid v1.0.0
[INFO] [stderr]   Downloaded object v0.29.0
[INFO] [stderr]   Downloaded deadpool-runtime v0.1.2
[INFO] [stderr]   Downloaded retain_mut v0.1.9
[INFO] [stderr]   Downloaded deadpool-sync v0.1.0
[INFO] [stderr]   Downloaded serde v1.0.148
[INFO] [stderr]   Downloaded tracing-tree v0.2.2
[INFO] [stderr]   Downloaded async-trait v0.1.59
[INFO] [stderr]   Downloaded tokio v1.22.0
[INFO] [stderr]   Downloaded gimli v0.26.2
[INFO] [stderr]   Downloaded color-eyre v0.6.2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+c7f6aa2869acdbf014d094c6e427e554e160b6db" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4bd62c36b1a85e15eea1af7f940159bb65374256581b45992a6485d181bb5927
[INFO] running `Command { std: "docker" "start" "-a" "4bd62c36b1a85e15eea1af7f940159bb65374256581b45992a6485d181bb5927", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4bd62c36b1a85e15eea1af7f940159bb65374256581b45992a6485d181bb5927", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4bd62c36b1a85e15eea1af7f940159bb65374256581b45992a6485d181bb5927", kill_on_drop: false }`
[INFO] [stdout] 4bd62c36b1a85e15eea1af7f940159bb65374256581b45992a6485d181bb5927
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+c7f6aa2869acdbf014d094c6e427e554e160b6db" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d413a44a9f5800e4f3dcff4327adc31a94eb5a7a032577995d1fb26dfe2ac4d2
[INFO] running `Command { std: "docker" "start" "-a" "d413a44a9f5800e4f3dcff4327adc31a94eb5a7a032577995d1fb26dfe2ac4d2", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.105
[INFO] [stderr]    Compiling libc v0.2.138
[INFO] [stderr]    Compiling proc-macro2 v1.0.47
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling serde_derive v1.0.148
[INFO] [stderr]    Compiling serde v1.0.148
[INFO] [stderr]    Compiling once_cell v1.16.0
[INFO] [stderr]    Compiling pin-project-lite v0.2.9
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling ahash v0.7.6
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.47/src/lib.rs:92:30
[INFO] [stdout]    |
[INFO] [stdout] 92 |     feature(proc_macro_span, proc_macro_span_shrink)
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling tinyvec_macros v0.1.0
[INFO] [stderr]    Compiling tinyvec v1.6.0
[INFO] [stderr]    Compiling tokio v1.22.0
[INFO] [stderr]    Compiling num-integer v0.1.45
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `proc-macro2` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "d413a44a9f5800e4f3dcff4327adc31a94eb5a7a032577995d1fb26dfe2ac4d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d413a44a9f5800e4f3dcff4327adc31a94eb5a7a032577995d1fb26dfe2ac4d2", kill_on_drop: false }`
[INFO] [stdout] d413a44a9f5800e4f3dcff4327adc31a94eb5a7a032577995d1fb26dfe2ac4d2