[INFO] fetching crate rdxl_scaffolding 0.1.0...
[INFO] testing rdxl_scaffolding-0.1.0 against 1.90.0 for beta-1.91-3
[INFO] extracting crate rdxl_scaffolding 0.1.0 into /workspace/builds/worker-7-tc1/source
[INFO] started tweaking crates.io crate rdxl_scaffolding 0.1.0
[INFO] finished tweaking crates.io crate rdxl_scaffolding 0.1.0
[INFO] tweaked toml for crates.io crate rdxl_scaffolding 0.1.0 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate rdxl_scaffolding 0.1.0 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate rdxl_scaffolding 0.1.0 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" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded structopt-derive v0.4.8
[INFO] [stderr]   Downloaded mxml_dep v0.1.3
[INFO] [stderr]   Downloaded html_parser v0.4.2
[INFO] [stderr]   Downloaded proc-macro-error-attr v1.0.2
[INFO] [stderr]   Downloaded pest_generator v2.1.3
[INFO] [stderr]   Downloaded sha-1 v0.8.2
[INFO] [stderr]   Downloaded pest_derive v2.1.0
[INFO] [stderr]   Downloaded anyhow v1.0.31
[INFO] [stderr]   Downloaded ucd-trie v0.1.3
[INFO] [stderr]   Downloaded serde_derive v1.0.113
[INFO] [stderr]   Downloaded pest_meta v2.1.3
[INFO] [stderr]   Downloaded syn v1.0.30
[INFO] [stderr]   Downloaded pest v2.1.3
[INFO] [stderr]   Downloaded serde v1.0.113
[INFO] [stderr]   Downloaded unicode-segmentation v1.6.0
[INFO] [stderr]   Downloaded serde_json v1.0.55
[INFO] [stderr]   Downloaded unicode-width v0.1.7
[INFO] [stderr]   Downloaded hermit-abi v0.1.14
[INFO] [stderr]   Downloaded syn-mid v0.5.0
[INFO] [stderr]   Downloaded clap v2.33.1
[INFO] [stderr]   Downloaded proc-macro-error v1.0.2
[INFO] [stderr]   Downloaded structopt v0.3.15
[INFO] [stderr]   Downloaded quote v1.0.6
[INFO] [stderr]   Downloaded mxml v0.1.2
[INFO] [stderr]   Downloaded proc-macro2 v1.0.18
[INFO] [stderr]   Downloaded rdxl v0.5.5
[INFO] [stderr]   Downloaded libc v0.2.71
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] fa8698b6efa1f5d8765fbe48b01637f25015c562c861040872d03b51a0cb07ab
[INFO] running `Command { std: "docker" "start" "-a" "fa8698b6efa1f5d8765fbe48b01637f25015c562c861040872d03b51a0cb07ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "fa8698b6efa1f5d8765fbe48b01637f25015c562c861040872d03b51a0cb07ab", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fa8698b6efa1f5d8765fbe48b01637f25015c562c861040872d03b51a0cb07ab", kill_on_drop: false }`
[INFO] [stdout] fa8698b6efa1f5d8765fbe48b01637f25015c562c861040872d03b51a0cb07ab
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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=warn" "-e" "RUSTDOCFLAGS=--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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fffa0f86cd0dc06a9c9f7a3acd4ff1fb01a0f1f2062ac0ad67d9cd8fd77d0ab7
[INFO] running `Command { std: "docker" "start" "-a" "fffa0f86cd0dc06a9c9f7a3acd4ff1fb01a0f1f2062ac0ad67d9cd8fd77d0ab7", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.18
[INFO] [stderr]    Compiling unicode-xid v0.2.0
[INFO] [stderr]    Compiling syn v1.0.30
[INFO] [stderr]    Compiling version_check v0.9.2
[INFO] [stderr]    Compiling libc v0.2.71
[INFO] [stderr]    Compiling serde_derive v1.0.113
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling ucd-trie v0.1.3
[INFO] [stderr]    Compiling unicode-width v0.1.7
[INFO] [stderr]    Compiling unicode-segmentation v1.6.0
[INFO] [stderr]    Compiling maplit v1.0.2
[INFO] [stderr]    Compiling serde v1.0.113
[INFO] [stderr]    Compiling pest v2.1.3
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling heck v0.3.1
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling ansi_term v0.11.0
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.2
[INFO] [stderr]    Compiling proc-macro-error v1.0.2
[INFO] [stderr]    Compiling anyhow v1.0.31
[INFO] [stderr]    Compiling serde_json v1.0.55
[INFO] [stderr]    Compiling pest_meta v2.1.3
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling itoa v0.4.6
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling quote v1.0.6
[INFO] [stderr]    Compiling clap v2.33.1
[INFO] [stderr]    Compiling syn-mid v0.5.0
[INFO] [stderr]    Compiling pest_generator v2.1.3
[INFO] [stderr]    Compiling thiserror-impl v1.0.20
[INFO] [stderr]    Compiling rdxl v0.5.5
[INFO] [stderr]    Compiling pest_derive v2.1.0
[INFO] [stderr]    Compiling thiserror v1.0.20
[INFO] [stderr]    Compiling structopt-derive v0.4.8
[INFO] [stderr]    Compiling structopt v0.3.15
[INFO] [stderr]    Compiling html_parser v0.4.2
[INFO] [stderr]    Compiling mxml_dep v0.1.3
[INFO] [stderr]    Compiling mxml v0.1.2
[INFO] [stderr]    Compiling rdxl_scaffolding v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/build_index.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(proc_macro_hygiene)]
[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 `rdxl_scaffolding` (bin "build_index") due to 1 previous error
[INFO] running `Command { std: "docker" "inspect" "fffa0f86cd0dc06a9c9f7a3acd4ff1fb01a0f1f2062ac0ad67d9cd8fd77d0ab7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fffa0f86cd0dc06a9c9f7a3acd4ff1fb01a0f1f2062ac0ad67d9cd8fd77d0ab7", kill_on_drop: false }`
[INFO] [stdout] fffa0f86cd0dc06a9c9f7a3acd4ff1fb01a0f1f2062ac0ad67d9cd8fd77d0ab7