[INFO] fetching crate scan-fonts 1.0.0...
[INFO] documenting scan-fonts-1.0.0 against 1.61.0 for beta-1.62-rustdoc-1
[INFO] extracting crate scan-fonts 1.0.0 into /workspace/builds/worker-11/source
[INFO] validating manifest of crates.io crate scan-fonts 1.0.0 on toolchain 1.61.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate scan-fonts 1.0.0
[INFO] finished tweaking crates.io crate scan-fonts 1.0.0
[INFO] tweaked toml for crates.io crate scan-fonts 1.0.0 written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.61.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded syn v0.13.11
[INFO] [stderr]   Downloaded proc-macro2 v0.3.8
[INFO] [stderr]   Downloaded quote v0.5.2
[INFO] [stderr]   Downloaded getset v0.0.6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "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] f792dbb03f020a9d66fa9dabfd4f67f2f0581ccd8a6bb1e1eafb2111fc927184
[INFO] running `Command { std: "docker" "start" "-a" "f792dbb03f020a9d66fa9dabfd4f67f2f0581ccd8a6bb1e1eafb2111fc927184", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f792dbb03f020a9d66fa9dabfd4f67f2f0581ccd8a6bb1e1eafb2111fc927184", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f792dbb03f020a9d66fa9dabfd4f67f2f0581ccd8a6bb1e1eafb2111fc927184", kill_on_drop: false }`
[INFO] [stdout] f792dbb03f020a9d66fa9dabfd4f67f2f0581ccd8a6bb1e1eafb2111fc927184
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "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:d190cb871061d98bc6d0581d85cb2ecb09a0f8a142ba5463de30be9999fc3251" "/opt/rustwide/cargo-home/bin/cargo" "+1.61.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] fd69ca3ae91f172c4c52268a3130195170f55e911cf3ef4ece5795eb3194672e
[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" "fd69ca3ae91f172c4c52268a3130195170f55e911cf3ef4ece5795eb3194672e", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.39
[INFO] [stderr]    Compiling unicode-ident v1.0.0
[INFO] [stderr]    Compiling syn v1.0.95
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]    Compiling cc v1.0.73
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]     Checking gimli v0.26.1
[INFO] [stderr]     Checking adler v1.0.2
[INFO] [stderr]    Compiling unicode-xid v0.2.3
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]     Checking rustc-demangle v0.1.21
[INFO] [stderr]    Compiling proc-macro2 v0.3.8
[INFO] [stderr]     Checking miniz_oxide v0.5.1
[INFO] [stderr]    Compiling quote v0.5.2
[INFO] [stderr]    Compiling syn v0.13.11
[INFO] [stderr]    Compiling backtrace v0.3.65
[INFO] [stderr]     Checking object v0.28.4
[INFO] [stderr]    Compiling quote v1.0.18
[INFO] [stderr]    Compiling getset v0.0.6
[INFO] [stderr]     Checking addr2line v0.17.0
[INFO] [stderr]    Compiling synstructure v0.12.6
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]  Documenting scan-fonts v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:6:12
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(try_from)]
[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 E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `scan-fonts`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name scan_fonts src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=ede723f732ff79f8 -L dependency=/opt/rustwide/target/debug/deps --extern failure=/opt/rustwide/target/debug/deps/libfailure-c88cfe258b39ebbc.rmeta --extern getset=/opt/rustwide/target/debug/deps/libgetset-148f7c7db9889a8c.so --cap-lints=warn --crate-version 1.0.0` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "fd69ca3ae91f172c4c52268a3130195170f55e911cf3ef4ece5795eb3194672e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "fd69ca3ae91f172c4c52268a3130195170f55e911cf3ef4ece5795eb3194672e", kill_on_drop: false }`
[INFO] [stdout] fd69ca3ae91f172c4c52268a3130195170f55e911cf3ef4ece5795eb3194672e