[INFO] cloning repository https://github.com/MBATheGamer/rustlings-solution
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/MBATheGamer/rustlings-solution" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMBATheGamer%2Frustlings-solution", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMBATheGamer%2Frustlings-solution'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 8caf870873e0c56a9a8ec6bfa93cd1bb9f5b2827
[INFO] checking MBATheGamer/rustlings-solution against try#9d63f825c0d409b0e1743a2c84b33f86965e5929 for pr-136968
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMBATheGamer%2Frustlings-solution" "/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/MBATheGamer/rustlings-solution on toolchain 9d63f825c0d409b0e1743a2c84b33f86965e5929
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+9d63f825c0d409b0e1743a2c84b33f86965e5929" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/MBATheGamer/rustlings-solution
[INFO] finished tweaking git repo https://github.com/MBATheGamer/rustlings-solution
[INFO] tweaked toml for git repo https://github.com/MBATheGamer/rustlings-solution written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/MBATheGamer/rustlings-solution 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" "+9d63f825c0d409b0e1743a2c84b33f86965e5929" "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-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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+9d63f825c0d409b0e1743a2c84b33f86965e5929" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] cfb324e830cd6573f75289a67a012cda2b1a7f24b9d6271be9ed94847411cbdc
[INFO] running `Command { std: "docker" "start" "-a" "cfb324e830cd6573f75289a67a012cda2b1a7f24b9d6271be9ed94847411cbdc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cfb324e830cd6573f75289a67a012cda2b1a7f24b9d6271be9ed94847411cbdc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cfb324e830cd6573f75289a67a012cda2b1a7f24b9d6271be9ed94847411cbdc", kill_on_drop: false }`
[INFO] [stdout] cfb324e830cd6573f75289a67a012cda2b1a7f24b9d6271be9ed94847411cbdc
[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@sha256:3959728d45483eb673ba100a951a6b9f5012970368db2a9e08e0ac9b67c8a5ad" "/opt/rustwide/cargo-home/bin/cargo" "+9d63f825c0d409b0e1743a2c84b33f86965e5929" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 5276e8ee60dac91713dbaa0c5561ee35248f6e0095ed59d89f0987e2c879097d
[INFO] running `Command { std: "docker" "start" "-a" "5276e8ee60dac91713dbaa0c5561ee35248f6e0095ed59d89f0987e2c879097d", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.53
[INFO] [stderr]    Compiling libc v0.2.150
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]    Compiling unicode-ident v1.0.8
[INFO] [stderr]    Compiling serde_derive v1.0.158
[INFO] [stderr]    Compiling serde v1.0.158
[INFO] [stderr]     Checking memchr v2.6.3
[INFO] [stderr]    Compiling crossbeam-utils v0.8.16
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]     Checking anstyle v1.0.3
[INFO] [stderr]     Checking utf8parse v0.2.1
[INFO] [stderr]     Checking equivalent v1.0.1
[INFO] [stderr]     Checking regex-syntax v0.6.29
[INFO] [stderr]     Checking hashbrown v0.14.0
[INFO] [stderr]    Compiling num-traits v0.2.15
[INFO] [stderr]    Compiling portable-atomic v1.4.3
[INFO] [stderr]     Checking colorchoice v1.0.0
[INFO] [stderr]     Checking anstyle-parse v0.2.1
[INFO] [stderr]     Checking anstyle-query v1.0.0
[INFO] [stderr]     Checking walkdir v2.3.3
[INFO] [stderr]     Checking either v1.9.0
[INFO] [stderr]     Checking winnow v0.5.15
[INFO] [stderr]     Checking anstream v0.5.0
[INFO] [stderr]     Checking predicates-core v1.0.6
[INFO] [stderr]    Compiling doc-comment v0.3.3
[INFO] [stderr]    Compiling serde_json v1.0.94
[INFO] [stderr]     Checking strsim v0.10.0
[INFO] [stderr]     Checking aho-corasick v0.7.20
[INFO] [stderr]    Compiling heck v0.4.1
[INFO] [stderr]     Checking clap_lex v0.5.1
[INFO] [stderr]     Checking itertools v0.10.5
[INFO] [stderr]     Checking regex-automata v0.3.8
[INFO] [stderr]     Checking itoa v1.0.6
[INFO] [stderr]     Checking indexmap v2.0.0
[INFO] [stderr]     Checking clap_builder v4.4.2
[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 difflib v0.4.0
[INFO] [stderr]     Checking ryu v1.0.13
[INFO] [stderr]     Checking number_prefix v0.4.0
[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" "5276e8ee60dac91713dbaa0c5561ee35248f6e0095ed59d89f0987e2c879097d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5276e8ee60dac91713dbaa0c5561ee35248f6e0095ed59d89f0987e2c879097d", kill_on_drop: false }`
[INFO] [stdout] 5276e8ee60dac91713dbaa0c5561ee35248f6e0095ed59d89f0987e2c879097d