[INFO] cloning repository https://github.com/macroexpansion/concurrency-exercise
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/macroexpansion/concurrency-exercise" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmacroexpansion%2Fconcurrency-exercise", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmacroexpansion%2Fconcurrency-exercise'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 66e35f6ecb6ca33a1786b855025093db4bcec266
[INFO] checking macroexpansion/concurrency-exercise against try#da4929024a7261062885cb3209c9d7fdc919d233 for pr-135536
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmacroexpansion%2Fconcurrency-exercise" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/macroexpansion/concurrency-exercise on toolchain da4929024a7261062885cb3209c9d7fdc919d233
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+da4929024a7261062885cb3209c9d7fdc919d233" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/macroexpansion/concurrency-exercise
[INFO] finished tweaking git repo https://github.com/macroexpansion/concurrency-exercise
[INFO] tweaked toml for git repo https://github.com/macroexpansion/concurrency-exercise written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/macroexpansion/concurrency-exercise 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" "+da4929024a7261062885cb3209c9d7fdc919d233" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+da4929024a7261062885cb3209c9d7fdc919d233" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bcc36965c536173149f9b21e0dbbb2ff3b9bbbb2bb437a86e3c52c30f1c806d7
[INFO] running `Command { std: "docker" "start" "-a" "bcc36965c536173149f9b21e0dbbb2ff3b9bbbb2bb437a86e3c52c30f1c806d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bcc36965c536173149f9b21e0dbbb2ff3b9bbbb2bb437a86e3c52c30f1c806d7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bcc36965c536173149f9b21e0dbbb2ff3b9bbbb2bb437a86e3c52c30f1c806d7", kill_on_drop: false }`
[INFO] [stdout] bcc36965c536173149f9b21e0dbbb2ff3b9bbbb2bb437a86e3c52c30f1c806d7
[INFO] checking macroexpansion/concurrency-exercise against try#da4929024a7261062885cb3209c9d7fdc919d233 for pr-135536
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmacroexpansion%2Fconcurrency-exercise" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/macroexpansion/concurrency-exercise on toolchain da4929024a7261062885cb3209c9d7fdc919d233
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+da4929024a7261062885cb3209c9d7fdc919d233" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/macroexpansion/concurrency-exercise
[INFO] finished tweaking git repo https://github.com/macroexpansion/concurrency-exercise
[INFO] tweaked toml for git repo https://github.com/macroexpansion/concurrency-exercise written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/macroexpansion/concurrency-exercise 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" "+da4929024a7261062885cb3209c9d7fdc919d233" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+da4929024a7261062885cb3209c9d7fdc919d233" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 40aa9bd9422879f87af8c5bb6e69db6c03530f9dea0d4df160a9cc5f2f480d23
[INFO] running `Command { std: "docker" "start" "-a" "40aa9bd9422879f87af8c5bb6e69db6c03530f9dea0d4df160a9cc5f2f480d23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "40aa9bd9422879f87af8c5bb6e69db6c03530f9dea0d4df160a9cc5f2f480d23", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "40aa9bd9422879f87af8c5bb6e69db6c03530f9dea0d4df160a9cc5f2f480d23", kill_on_drop: false }`
[INFO] [stdout] 40aa9bd9422879f87af8c5bb6e69db6c03530f9dea0d4df160a9cc5f2f480d23
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:819108c5571ea2e421544af4d832f968d213c87fbe3707a016657f43d2f853bc" "/opt/rustwide/cargo-home/bin/cargo" "+da4929024a7261062885cb3209c9d7fdc919d233" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 30f3e79662ecdea52b162ab3cb902cb35a35afe337a786feda1db40ec27fbb80
[INFO] running `Command { std: "docker" "start" "-a" "30f3e79662ecdea52b162ab3cb902cb35a35afe337a786feda1db40ec27fbb80", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.46
[INFO] [stderr]    Compiling quote v1.0.21
[INFO] [stderr]    Compiling unicode-ident v1.0.4
[INFO] [stderr]    Compiling libc v0.2.134
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling syn v1.0.101
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling futures-core v0.3.24
[INFO] [stderr]    Compiling futures-task v0.3.24
[INFO] [stderr]    Compiling futures-channel v0.3.24
[INFO] [stderr]     Checking pin-project-lite v0.2.9
[INFO] [stderr]    Compiling futures-util v0.3.24
[INFO] [stderr]    Compiling parking_lot_core v0.9.3
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]     Checking futures-sink v0.3.24
[INFO] [stderr]     Checking pin-utils v0.1.0
[INFO] [stderr]     Checking smallvec v1.10.0
[INFO] [stderr]     Checking futures-io v0.3.24
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling async-trait v0.1.57
[INFO] [stderr]     Checking ppv-lite86 v0.2.16
[INFO] [stderr]    Compiling thiserror v1.0.37
[INFO] [stderr]     Checking bytes v1.2.1
[INFO] [stderr]    Compiling convert_case v0.4.0
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.46/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 slab v0.4.7
[INFO] [stderr]    Compiling lock_api v0.4.9
[INFO] [stderr]    Compiling tokio v1.21.2
[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" "30f3e79662ecdea52b162ab3cb902cb35a35afe337a786feda1db40ec27fbb80", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "30f3e79662ecdea52b162ab3cb902cb35a35afe337a786feda1db40ec27fbb80", kill_on_drop: false }`
[INFO] [stdout] 30f3e79662ecdea52b162ab3cb902cb35a35afe337a786feda1db40ec27fbb80