[INFO] cloning repository https://github.com/tukanoidd/config_example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/tukanoidd/config_example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftukanoidd%2Fconfig_example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftukanoidd%2Fconfig_example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 472bc8b7d29d433dec2ce542fb5677211a16e86c
[INFO] checking tukanoidd/config_example against 1.95.0 for pr-155915
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Ftukanoidd%2Fconfig_example" "/workspace/builds/worker-6-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc1/source'...
[INFO] [stderr] done.
[INFO] removed /workspace/builds/worker-6-tc1/source/rust-toolchain.toml
[INFO] started tweaking git repo https://github.com/tukanoidd/config_example
[INFO] finished tweaking git repo https://github.com/tukanoidd/config_example
[INFO] tweaked toml for git repo https://github.com/tukanoidd/config_example written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/tukanoidd/config_example on toolchain 1.95.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.95.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/tukanoidd/config_example 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" "+1.95.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded darling_macro v0.20.8
[INFO] [stderr]   Downloaded num v0.4.1
[INFO] [stderr]   Downloaded indexmap v2.2.4
[INFO] [stderr]   Downloaded darling v0.20.8
[INFO] [stderr]   Downloaded darling_core v0.20.8
[INFO] [stderr]   Downloaded syn v2.0.52
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 2f7e680e1c4bb3753d406a801894274500c21e5496fd4bf09869e3b055bd2bc9
[INFO] running `Command { std: "docker" "start" "-a" "2f7e680e1c4bb3753d406a801894274500c21e5496fd4bf09869e3b055bd2bc9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "2f7e680e1c4bb3753d406a801894274500c21e5496fd4bf09869e3b055bd2bc9", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2f7e680e1c4bb3753d406a801894274500c21e5496fd4bf09869e3b055bd2bc9", kill_on_drop: false }`
[INFO] [stdout] 2f7e680e1c4bb3753d406a801894274500c21e5496fd4bf09869e3b055bd2bc9
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+1.95.0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 839bc57651445ccda91e988d5ce816d656e1996f60247c1d829f3c8e21338c0a
[INFO] running `Command { std: "docker" "start" "-a" "839bc57651445ccda91e988d5ce816d656e1996f60247c1d829f3c8e21338c0a", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.78
[INFO] [stderr]     Checking unicode-ident v1.0.12
[INFO] [stderr]     Checking equivalent v1.0.1
[INFO] [stderr]    Compiling toml_datetime v0.6.5
[INFO] [stderr]     Checking hashbrown v0.14.3
[INFO] [stderr]    Compiling winnow v0.5.40
[INFO] [stderr]     Checking fnv v1.0.7
[INFO] [stderr]     Checking ident_case v1.0.1
[INFO] [stderr]    Compiling num-traits v0.2.18
[INFO] [stderr]    Compiling num-bigint v0.4.4
[INFO] [stderr]    Compiling indexmap v2.2.4
[INFO] [stderr]    Compiling num-rational v0.4.1
[INFO] [stderr]     Checking strsim v0.10.0
[INFO] [stderr]     Checking quote v1.0.35
[INFO] [stderr]    Compiling syn v2.0.52
[INFO] [stderr]    Compiling syn v1.0.109
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]     Checking num-integer v0.1.46
[INFO] [stderr]     Checking num-complex v0.4.5
[INFO] [stderr]     Checking num-iter v0.1.44
[INFO] [stderr]     Checking toml_edit v0.21.1
[INFO] [stderr]     Checking proc-macro-error v1.0.4
[INFO] [stderr]     Checking proc-macro-crate v3.1.0
[INFO] [stderr]     Checking darling_core v0.20.8
[INFO] [stderr]     Checking num v0.4.1
[INFO] [stderr]    Compiling derive_more v0.99.17
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/darling_core-0.20.8/src/lib.rs:2:38
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![cfg_attr(feature = "diagnostics", feature(proc_macro_diagnostic))]
[INFO] [stdout]   |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `darling_core` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "839bc57651445ccda91e988d5ce816d656e1996f60247c1d829f3c8e21338c0a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "839bc57651445ccda91e988d5ce816d656e1996f60247c1d829f3c8e21338c0a", kill_on_drop: false }`
[INFO] [stdout] 839bc57651445ccda91e988d5ce816d656e1996f60247c1d829f3c8e21338c0a