[INFO] cloning repository https://github.com/nstylo/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/nstylo/rustlings-solutions" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnstylo%2Frustlings-solutions", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnstylo%2Frustlings-solutions'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] edee45a993ee9db6638bc0163754f46d9a2ba6ac
[INFO] testing nstylo/rustlings-solutions against try#0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6 for pr-137122-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnstylo%2Frustlings-solutions" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/nstylo/rustlings-solutions
[INFO] finished tweaking git repo https://github.com/nstylo/rustlings-solutions
[INFO] tweaked toml for git repo https://github.com/nstylo/rustlings-solutions written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/nstylo/rustlings-solutions on toolchain 0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/nstylo/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" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "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-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 4153fa3cc1e757fae9b63ab43697c08c791dd28e7644235a77d68c7799d0602c
[INFO] running `Command { std: "docker" "start" "-a" "4153fa3cc1e757fae9b63ab43697c08c791dd28e7644235a77d68c7799d0602c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "4153fa3cc1e757fae9b63ab43697c08c791dd28e7644235a77d68c7799d0602c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "4153fa3cc1e757fae9b63ab43697c08c791dd28e7644235a77d68c7799d0602c", kill_on_drop: false }`
[INFO] [stdout] 4153fa3cc1e757fae9b63ab43697c08c791dd28e7644235a77d68c7799d0602c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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@sha256:90999bfc7ae267e83380e433d8e61a7c072ca6729e92edbae886d3423b3a6f4c" "/opt/rustwide/cargo-home/bin/cargo" "+0936b3db0ae648ba2d5b60eb08cf4faf2ddab0c6" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c9772fbb9c2fa35f88579710aaf5bc92d4b264cd32f2b2720eea2eabc58d7e66
[INFO] running `Command { std: "docker" "start" "-a" "c9772fbb9c2fa35f88579710aaf5bc92d4b264cd32f2b2720eea2eabc58d7e66", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.53
[INFO] [stderr]    Compiling libc v0.2.140
[INFO] [stderr]    Compiling unicode-ident v1.0.8
[INFO] [stderr]    Compiling quote v1.0.26
[INFO] [stderr]    Compiling serde_derive v1.0.158
[INFO] [stderr]    Compiling serde v1.0.158
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling utf8parse v0.2.1
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling anstyle-parse v0.2.1
[INFO] [stderr]    Compiling hashbrown v0.14.0
[INFO] [stderr]    Compiling equivalent v1.0.1
[INFO] [stderr]    Compiling colorchoice v1.0.0
[INFO] [stderr]    Compiling portable-atomic v1.4.3
[INFO] [stderr]    Compiling anstyle v1.0.3
[INFO] [stderr]    Compiling anstyle-query v1.0.0
[INFO] [stderr]    Compiling memchr v2.6.3
[INFO] [stderr]    Compiling same-file v1.0.6
[INFO] [stderr]    Compiling slab v0.4.8
[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]    Compiling lazycell v1.3.0
[INFO] [stderr]    Compiling anstream v0.5.0
[INFO] [stderr]    Compiling winnow v0.5.15
[INFO] [stderr]    Compiling heck v0.4.1
[INFO] [stderr]    Compiling unicode-width v0.1.10
[INFO] [stderr]    Compiling clap_lex v0.5.1
[INFO] [stderr]    Compiling bitflags v1.3.2
[INFO] [stderr]    Compiling strsim v0.10.0
[INFO] [stderr]    Compiling lazy_static v1.4.0
[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" "c9772fbb9c2fa35f88579710aaf5bc92d4b264cd32f2b2720eea2eabc58d7e66", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c9772fbb9c2fa35f88579710aaf5bc92d4b264cd32f2b2720eea2eabc58d7e66", kill_on_drop: false }`
[INFO] [stdout] c9772fbb9c2fa35f88579710aaf5bc92d4b264cd32f2b2720eea2eabc58d7e66