[INFO] cloning repository https://github.com/BalaM314/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/BalaM314/rustlings-solutions" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBalaM314%2Frustlings-solutions", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBalaM314%2Frustlings-solutions'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 748b83814d1d12c79e6c090020a15879f34c9d8d
[INFO] checking BalaM314/rustlings-solutions against try#73ffebff6f34db7eb167bf9edcf2afa19c3073e9 for pr-147841
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FBalaM314%2Frustlings-solutions" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/BalaM314/rustlings-solutions
[INFO] finished tweaking git repo https://github.com/BalaM314/rustlings-solutions
[INFO] tweaked toml for git repo https://github.com/BalaM314/rustlings-solutions written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/BalaM314/rustlings-solutions on toolchain 73ffebff6f34db7eb167bf9edcf2afa19c3073e9
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+73ffebff6f34db7eb167bf9edcf2afa19c3073e9" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/BalaM314/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" "+73ffebff6f34db7eb167bf9edcf2afa19c3073e9" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+73ffebff6f34db7eb167bf9edcf2afa19c3073e9" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e6bdf7fd8883cfe5fde3c5c0133d5a517676d29f840bef61ae7754cc8638e59c
[INFO] running `Command { std: "docker" "start" "-a" "e6bdf7fd8883cfe5fde3c5c0133d5a517676d29f840bef61ae7754cc8638e59c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e6bdf7fd8883cfe5fde3c5c0133d5a517676d29f840bef61ae7754cc8638e59c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e6bdf7fd8883cfe5fde3c5c0133d5a517676d29f840bef61ae7754cc8638e59c", kill_on_drop: false }`
[INFO] [stdout] e6bdf7fd8883cfe5fde3c5c0133d5a517676d29f840bef61ae7754cc8638e59c
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+73ffebff6f34db7eb167bf9edcf2afa19c3073e9" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 91f9e75249a84bdf9c61c163b107d156ab7bfb7df32638743cbc8eba80bd0014
[INFO] running `Command { std: "docker" "start" "-a" "91f9e75249a84bdf9c61c163b107d156ab7bfb7df32638743cbc8eba80bd0014", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.53
[INFO] [stderr]    Compiling libc v0.2.140
[INFO] [stderr]    Compiling serde_derive v1.0.158
[INFO] [stderr]    Compiling serde v1.0.158
[INFO] [stderr]     Checking regex-syntax v0.6.29
[INFO] [stderr]    Compiling serde_json v1.0.94
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling argh_shared v0.1.10
[INFO] [stderr]    Compiling escargot v0.4.0
[INFO] [stderr]     Checking predicates-core v1.0.6
[INFO] [stderr]     Checking walkdir v2.3.3
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[INFO] [stderr]     Checking termtree v0.4.1
[INFO] [stderr]     Checking home v0.5.4
[INFO] [stderr]     Checking predicates-tree v1.0.9
[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] [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" "91f9e75249a84bdf9c61c163b107d156ab7bfb7df32638743cbc8eba80bd0014", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "91f9e75249a84bdf9c61c163b107d156ab7bfb7df32638743cbc8eba80bd0014", kill_on_drop: false }`
[INFO] [stdout] 91f9e75249a84bdf9c61c163b107d156ab7bfb7df32638743cbc8eba80bd0014
