[INFO] cloning repository https://github.com/LearningOS/rust-rustlings-MichaelYu781
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/LearningOS/rust-rustlings-MichaelYu781" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLearningOS%2Frust-rustlings-MichaelYu781", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLearningOS%2Frust-rustlings-MichaelYu781'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 13c803955d2c33b4001d5a62158b5c5b50ba6e33
[INFO] checking LearningOS/rust-rustlings-MichaelYu781/13c803955d2c33b4001d5a62158b5c5b50ba6e33 against master#4847d6a9d07d4be9ba3196f6ad444af2d7bdde72 for pr-134276
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FLearningOS%2Frust-rustlings-MichaelYu781" "/workspace/builds/worker-5-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/LearningOS/rust-rustlings-MichaelYu781 on toolchain 4847d6a9d07d4be9ba3196f6ad444af2d7bdde72
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+4847d6a9d07d4be9ba3196f6ad444af2d7bdde72" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/LearningOS/rust-rustlings-MichaelYu781
[INFO] finished tweaking git repo https://github.com/LearningOS/rust-rustlings-MichaelYu781
[INFO] tweaked toml for git repo https://github.com/LearningOS/rust-rustlings-MichaelYu781 written to /workspace/builds/worker-5-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/LearningOS/rust-rustlings-MichaelYu781 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" "+4847d6a9d07d4be9ba3196f6ad444af2d7bdde72" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+4847d6a9d07d4be9ba3196f6ad444af2d7bdde72" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 541ddb2c29942be8d61a444b747089a0e4c2bddb7b349fdeecb5b91802950fe1
[INFO] running `Command { std: "docker" "start" "-a" "541ddb2c29942be8d61a444b747089a0e4c2bddb7b349fdeecb5b91802950fe1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "541ddb2c29942be8d61a444b747089a0e4c2bddb7b349fdeecb5b91802950fe1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "541ddb2c29942be8d61a444b747089a0e4c2bddb7b349fdeecb5b91802950fe1", kill_on_drop: false }`
[INFO] [stdout] 541ddb2c29942be8d61a444b747089a0e4c2bddb7b349fdeecb5b91802950fe1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+4847d6a9d07d4be9ba3196f6ad444af2d7bdde72" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 56668d7b81c59f0778c4f98b4b2836e3d348d3eb2dbe8bda20f0f5c0332f4dcd
[INFO] running `Command { std: "docker" "start" "-a" "56668d7b81c59f0778c4f98b4b2836e3d348d3eb2dbe8bda20f0f5c0332f4dcd", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.141
[INFO] [stderr]    Compiling proc-macro2 v1.0.56
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]    Compiling unicode-ident v1.0.8
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling serde_derive v1.0.159
[INFO] [stderr]    Compiling serde v1.0.159
[INFO] [stderr]    Compiling lock_api v0.4.9
[INFO] [stderr]    Compiling parking_lot_core v0.9.7
[INFO] [stderr]    Compiling serde_json v1.0.95
[INFO] [stderr]     Checking regex-syntax v0.6.29
[INFO] [stderr]     Checking itoa v1.0.6
[INFO] [stderr]     Checking ryu v1.0.13
[INFO] [stderr]     Checking aho-corasick v0.7.20
[INFO] [stderr]     Checking smallvec v1.10.0
[INFO] [stderr]     Checking scopeguard v1.1.0
[INFO] [stderr]    Compiling tokio v1.27.0
[INFO] [stderr]     Checking pin-project-lite v0.2.9
[INFO] [stderr]     Checking home v0.5.4
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/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" "56668d7b81c59f0778c4f98b4b2836e3d348d3eb2dbe8bda20f0f5c0332f4dcd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "56668d7b81c59f0778c4f98b4b2836e3d348d3eb2dbe8bda20f0f5c0332f4dcd", kill_on_drop: false }`
[INFO] [stdout] 56668d7b81c59f0778c4f98b4b2836e3d348d3eb2dbe8bda20f0f5c0332f4dcd