[INFO] cloning repository https://github.com/asirrosa/rustlings-solutions
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/asirrosa/rustlings-solutions" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fasirrosa%2Frustlings-solutions", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fasirrosa%2Frustlings-solutions'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c73fd655eb3a8f22387a464a60c1ffcda4f6c38d
[INFO] checking asirrosa/rustlings-solutions against try#fc545c6b951a304df08b327c158f92678582f435 for pr-140557
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fasirrosa%2Frustlings-solutions" "/workspace/builds/worker-5-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-5-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/asirrosa/rustlings-solutions on toolchain fc545c6b951a304df08b327c158f92678582f435
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+fc545c6b951a304df08b327c158f92678582f435" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/asirrosa/rustlings-solutions
[INFO] finished tweaking git repo https://github.com/asirrosa/rustlings-solutions
[INFO] tweaked toml for git repo https://github.com/asirrosa/rustlings-solutions written to /workspace/builds/worker-5-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/asirrosa/rustlings-solutions 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" "+fc545c6b951a304df08b327c158f92678582f435" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+fc545c6b951a304df08b327c158f92678582f435" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 323798b18c992ca229b0bde044f6b4bc414a59d3b6733c01794046f5b092dace
[INFO] running `Command { std: "docker" "start" "-a" "323798b18c992ca229b0bde044f6b4bc414a59d3b6733c01794046f5b092dace", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "323798b18c992ca229b0bde044f6b4bc414a59d3b6733c01794046f5b092dace", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "323798b18c992ca229b0bde044f6b4bc414a59d3b6733c01794046f5b092dace", kill_on_drop: false }`
[INFO] [stdout] 323798b18c992ca229b0bde044f6b4bc414a59d3b6733c01794046f5b092dace
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+fc545c6b951a304df08b327c158f92678582f435" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c867fb2f59d0c022cc0b5d3908451624412d3f807fc4506ac1c9aa650d111903
[INFO] running `Command { std: "docker" "start" "-a" "c867fb2f59d0c022cc0b5d3908451624412d3f807fc4506ac1c9aa650d111903", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.53
[INFO] [stderr]    Compiling serde_derive v1.0.158
[INFO] [stderr]    Compiling libc v0.2.140
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling serde v1.0.158
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]     Checking regex-syntax v0.6.29
[INFO] [stderr]     Checking aho-corasick v0.7.20
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]     Checking same-file v1.0.6
[INFO] [stderr]    Compiling escargot v0.4.0
[INFO] [stderr]     Checking lazycell v1.3.0
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/proc-macro2-1.0.53/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]     Checking unicode-width v0.1.10
[INFO] [stderr]     Checking predicates-core v1.0.6
[INFO] [stderr]     Checking bitflags v1.3.2
[INFO] [stderr]    Compiling argh_shared v0.1.10
[INFO] [stderr]     Checking walkdir v2.3.3
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking termtree v0.4.1
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[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" "c867fb2f59d0c022cc0b5d3908451624412d3f807fc4506ac1c9aa650d111903", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c867fb2f59d0c022cc0b5d3908451624412d3f807fc4506ac1c9aa650d111903", kill_on_drop: false }`
[INFO] [stdout] c867fb2f59d0c022cc0b5d3908451624412d3f807fc4506ac1c9aa650d111903