[INFO] cloning repository https://github.com/SubstrateDevAcademy/v1-exercise-4
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/SubstrateDevAcademy/v1-exercise-4" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSubstrateDevAcademy%2Fv1-exercise-4", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSubstrateDevAcademy%2Fv1-exercise-4'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d2033c04bacc91f0e125dd70e67b7200209b1cd0
[INFO] testing SubstrateDevAcademy/v1-exercise-4 against beta-2021-09-08 for beta-1.56-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FSubstrateDevAcademy%2Fv1-exercise-4" "/workspace/builds/worker-3/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/SubstrateDevAcademy/v1-exercise-4 on toolchain beta-2021-09-08
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/SubstrateDevAcademy/v1-exercise-4
[INFO] finished tweaking git repo https://github.com/SubstrateDevAcademy/v1-exercise-4
[INFO] tweaked toml for git repo https://github.com/SubstrateDevAcademy/v1-exercise-4 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/SubstrateDevAcademy/v1-exercise-4 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-09-08" "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-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] cdd5228b1a2bc4185f0da9e3a69bd9467946841722c9bff0ddd28dcd3f3fa4c1
[INFO] running `Command { std: "docker" "start" "-a" "cdd5228b1a2bc4185f0da9e3a69bd9467946841722c9bff0ddd28dcd3f3fa4c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cdd5228b1a2bc4185f0da9e3a69bd9467946841722c9bff0ddd28dcd3f3fa4c1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cdd5228b1a2bc4185f0da9e3a69bd9467946841722c9bff0ddd28dcd3f3fa4c1", kill_on_drop: false }`
[INFO] [stdout] cdd5228b1a2bc4185f0da9e3a69bd9467946841722c9bff0ddd28dcd3f3fa4c1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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=warn" "-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:a89201d6b5b9fd45c15d5952ece0a0129e7e80cb26ec023fd59cf09bc26f1604" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-09-08" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 62aaf597b3058aed9941352c2fcac8c4ab6c72ace6515fbfadc3e7abf8ac165c
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "62aaf597b3058aed9941352c2fcac8c4ab6c72ace6515fbfadc3e7abf8ac165c", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling libc v0.2.82
[INFO] [stderr]    Compiling log v0.4.13
[INFO] [stderr]    Compiling serde_derive v1.0.119
[INFO] [stderr]    Compiling serde v1.0.119
[INFO] [stderr]    Compiling byteorder v1.4.2
[INFO] [stderr]    Compiling futures-core v0.3.11
[INFO] [stderr]    Compiling futures-io v0.3.11
[INFO] [stderr]    Compiling futures-sink v0.3.11
[INFO] [stderr]    Compiling regex-syntax v0.6.22
[INFO] [stderr]    Compiling serde_json v1.0.61
[INFO] [stderr]    Compiling tiny-keccak v2.0.2
[INFO] [stderr]    Compiling sp-std v2.0.1
[INFO] [stderr]    Compiling multimap v0.8.2
[INFO] [stderr]    Compiling data-encoding v2.3.1
[INFO] [stderr]    Compiling wasm-bindgen-shared v0.2.69
[INFO] [stderr]    Compiling wasm-bindgen v0.2.69
[INFO] [stderr]    Compiling slog v2.7.0
[INFO] [stderr]    Compiling arc-swap v1.2.0
[INFO] [stderr]    Compiling sc-consensus-slots v0.8.1
[INFO] [stderr]    Compiling thread_local v1.1.0
[INFO] [stderr]    Compiling indexmap v1.6.1
[INFO] [stderr]    Compiling hashbrown v0.8.2
[INFO] [stderr]    Compiling tokio-service v0.1.0
[INFO] [stderr]    Compiling futures-channel v0.3.11
[INFO] [stderr]    Compiling quicksink v0.1.2
[INFO] [stderr]    Compiling wast v31.0.0
[INFO] [stderr]    Compiling substrate-build-script-utils v2.0.1
[INFO] [stderr]    Compiling lru v0.6.3
[INFO] [stderr]    Compiling dns-parser v0.8.0
[INFO] [stderr]    Compiling parity-wasm v0.32.0
[INFO] [stderr]    Compiling hashbrown v0.1.8
[INFO] [stderr]    Compiling async-channel v1.5.1
[INFO] [stderr]    Compiling futures-lite v1.11.3
[INFO] [stderr]    Compiling bstr v0.2.14
[INFO] [stderr]    Compiling uint v0.8.5
[INFO] [stderr]    Compiling idna v0.1.5
[INFO] [stderr]    Compiling tokio-sync v0.2.0-alpha.6
[INFO] [stderr]    Compiling tokio-executor v0.1.10
[INFO] [stderr]    Compiling block-buffer v0.7.3
[INFO] [stderr]    Compiling block-buffer v0.9.0
[INFO] [stderr]    Compiling universal-hash v0.4.0
[INFO] [stderr]    Compiling crypto-mac v0.8.0
[INFO] [stderr]    Compiling node-template v2.0.1 (/opt/rustwide/workdir/node)
[INFO] [stderr]    Compiling futures-macro v0.3.11
[INFO] [stderr]    Compiling tracing-attributes v0.1.11
[INFO] [stderr]    Compiling impl-trait-for-tuples v0.1.3
[INFO] [stderr]    Compiling ref-cast-impl v1.0.6
[INFO] [stderr]    Compiling sp-debug-derive v2.0.1
[INFO] [stderr]    Compiling derive_more v0.99.11
[INFO] [stderr]    Compiling dyn-clonable-impl v0.9.0
[INFO] [stderr]    Compiling prost-derive v0.6.1
[INFO] [stderr]    Compiling pin-project-internal v1.0.4
[INFO] [stderr]    Compiling asn1_der_derive v0.1.2
[INFO] [stderr]    Compiling minicbor-derive v0.4.1
[INFO] [stdout] error[E0034]: multiple applicable items in scope
[INFO] [stdout]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/prost-derive-0.6.1/src/lib.rs:111:14
[INFO] [stdout]     |
[INFO] [stdout] 111 |             .intersperse(quote!(|));
[INFO] [stdout]     |              ^^^^^^^^^^^ multiple `intersperse` found
[INFO] [stdout]     |
[INFO] [stdout]     = note: candidate #1 is defined in an impl of the trait `Iterator` for the type `Map<I, F>`
[INFO] [stdout]     = note: candidate #2 is defined in an impl of the trait `Itertools` for the type `T`
[INFO] [stdout] help: disambiguate the associated function for candidate #1
[INFO] [stdout]     |
[INFO] [stdout] 107 ~         let tags = Iterator::intersperse(field
[INFO] [stdout] 108 +             .tags()
[INFO] [stdout] 109 +             .into_iter()
[INFO] [stdout] 110 +             .map(|tag| quote!(#tag)), {
[INFO] [stdout] 111 +         let mut _s = $crate::__private::TokenStream::new();
[INFO] [stdout] 112 +         $crate::quote_each_token!(_s $($tt)*);
[INFO] [stdout]   ...
[INFO] [stdout] help: disambiguate the associated function for candidate #2
[INFO] [stdout]     |
[INFO] [stdout] 107 ~         let tags = Itertools::intersperse(field
[INFO] [stdout] 108 +             .tags()
[INFO] [stdout] 109 +             .into_iter()
[INFO] [stdout] 110 +             .map(|tag| quote!(#tag)), {
[INFO] [stdout] 111 +         let mut _s = $crate::__private::TokenStream::new();
[INFO] [stdout] 112 +         $crate::quote_each_token!(_s $($tt)*);
[INFO] [stdout]   ...
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0034`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `prost-derive` due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "62aaf597b3058aed9941352c2fcac8c4ab6c72ace6515fbfadc3e7abf8ac165c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "62aaf597b3058aed9941352c2fcac8c4ab6c72ace6515fbfadc3e7abf8ac165c", kill_on_drop: false }`
[INFO] [stdout] 62aaf597b3058aed9941352c2fcac8c4ab6c72ace6515fbfadc3e7abf8ac165c