[INFO] fetching crate krab 0.1.3...
[INFO] checking krab-0.1.3 against try#a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d for pr-145342-1
[INFO] extracting crate krab 0.1.3 into /workspace/builds/worker-4-tc2/source
[INFO] started tweaking crates.io crate krab 0.1.3
[INFO] finished tweaking crates.io crate krab 0.1.3
[INFO] tweaked toml for crates.io crate krab 0.1.3 written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate krab 0.1.3 on toolchain a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate krab 0.1.3 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" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c7b77d6c995812595fe66f30c4931c04806dbaa7ebb26b3e97deba0b341412e3
[INFO] running `Command { std: "docker" "start" "-a" "c7b77d6c995812595fe66f30c4931c04806dbaa7ebb26b3e97deba0b341412e3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c7b77d6c995812595fe66f30c4931c04806dbaa7ebb26b3e97deba0b341412e3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c7b77d6c995812595fe66f30c4931c04806dbaa7ebb26b3e97deba0b341412e3", kill_on_drop: false }`
[INFO] [stdout] c7b77d6c995812595fe66f30c4931c04806dbaa7ebb26b3e97deba0b341412e3
[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" "-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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+a4980311fb7bb9e7893708e6bd3fbbfb2819fd3d" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] d6b7f364cfef4b43563d01b5d961103c2a513d65b9c96e07d95f82090fb6cdb2
[INFO] running `Command { std: "docker" "start" "-a" "d6b7f364cfef4b43563d01b5d961103c2a513d65b9c96e07d95f82090fb6cdb2", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.56
[INFO] [stderr]    Compiling unicode-ident v1.0.8
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]    Compiling libc v0.2.141
[INFO] [stderr]    Compiling thiserror v1.0.40
[INFO] [stderr]     Checking lazy_static v1.4.0
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.56/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] [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" "d6b7f364cfef4b43563d01b5d961103c2a513d65b9c96e07d95f82090fb6cdb2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d6b7f364cfef4b43563d01b5d961103c2a513d65b9c96e07d95f82090fb6cdb2", kill_on_drop: false }`
[INFO] [stdout] d6b7f364cfef4b43563d01b5d961103c2a513d65b9c96e07d95f82090fb6cdb2