[INFO] cloning repository https://github.com/zbrachinara/nand2tetris-assembler
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/zbrachinara/nand2tetris-assembler" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzbrachinara%2Fnand2tetris-assembler", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzbrachinara%2Fnand2tetris-assembler'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 9044a61fb1b4e1405dcca2798911af58d4f719eb
[INFO] documenting zbrachinara/nand2tetris-assembler against 1.61.0 for beta-1.62-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fzbrachinara%2Fnand2tetris-assembler" "/workspace/builds/worker-6/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/zbrachinara/nand2tetris-assembler 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 git repo https://github.com/zbrachinara/nand2tetris-assembler
[INFO] finished tweaking git repo https://github.com/zbrachinara/nand2tetris-assembler
[INFO] tweaked toml for git repo https://github.com/zbrachinara/nand2tetris-assembler written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/zbrachinara/nand2tetris-assembler already has a lockfile, it will not be regenerated
[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 strum v0.24.0
[INFO] [stderr]   Downloaded bytecount v0.6.2
[INFO] [stderr]   Downloaded nom_locate v4.0.0
[INFO] [stderr]   Downloaded strum_macros v0.24.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] [stdout] b76d6b41f001ac67f44230875e2c6aae0909b500dbf8a10a94e234e9cf371881
[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" "b76d6b41f001ac67f44230875e2c6aae0909b500dbf8a10a94e234e9cf371881", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b76d6b41f001ac67f44230875e2c6aae0909b500dbf8a10a94e234e9cf371881", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b76d6b41f001ac67f44230875e2c6aae0909b500dbf8a10a94e234e9cf371881", kill_on_drop: false }`
[INFO] [stdout] b76d6b41f001ac67f44230875e2c6aae0909b500dbf8a10a94e234e9cf371881
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 1da2f9940a987972557f39055cee842f3da934ffea03b4bb79e4a1f9809aa30c
[INFO] running `Command { std: "docker" "start" "-a" "1da2f9940a987972557f39055cee842f3da934ffea03b4bb79e4a1f9809aa30c", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling proc-macro2 v1.0.36
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]    Compiling syn v1.0.89
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling rustversion v1.0.6
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking minimal-lexical v0.2.1
[INFO] [stderr]     Checking strum v0.24.0
[INFO] [stderr]     Checking libc v0.2.121
[INFO] [stderr]    Compiling proc-macro-error-attr v1.0.4
[INFO] [stderr]    Compiling proc-macro-error v1.0.4
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking nom v7.1.1
[INFO] [stderr]     Checking clap v2.34.0
[INFO] [stderr]    Compiling quote v1.0.15
[INFO] [stderr]     Checking nom_locate v4.0.0
[INFO] [stderr]    Compiling thiserror-impl v1.0.30
[INFO] [stderr]    Compiling structopt-derive v0.4.18
[INFO] [stderr]    Compiling strum_macros v0.24.0
[INFO] [stderr]     Checking thiserror v1.0.30
[INFO] [stderr]     Checking structopt v0.3.26
[INFO] [stderr]  Documenting nand2tetris-assembler v0.4.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iter_intersperse)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:2:12
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(iterator_try_collect)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not document `nand2tetris-assembler`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2021 --crate-type bin --crate-name nand2tetris_assembler src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=28879c6e3167d320 -L dependency=/opt/rustwide/target/debug/deps --extern bitflags=/opt/rustwide/target/debug/deps/libbitflags-22d7f70832a3b85e.rmeta --extern nom=/opt/rustwide/target/debug/deps/libnom-e263bb04571c8f8c.rmeta --extern nom_locate=/opt/rustwide/target/debug/deps/libnom_locate-48e0639d25db336a.rmeta --extern structopt=/opt/rustwide/target/debug/deps/libstructopt-fb06390c149b823c.rmeta --extern strum=/opt/rustwide/target/debug/deps/libstrum-4eec818919ddb563.rmeta --extern strum_macros=/opt/rustwide/target/debug/deps/libstrum_macros-b4a9dc5b192686cd.so --extern thiserror=/opt/rustwide/target/debug/deps/libthiserror-86ca1fd07d8cd104.rmeta --cap-lints=warn --crate-version 0.4.2` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "1da2f9940a987972557f39055cee842f3da934ffea03b4bb79e4a1f9809aa30c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1da2f9940a987972557f39055cee842f3da934ffea03b4bb79e4a1f9809aa30c", kill_on_drop: false }`
[INFO] [stdout] 1da2f9940a987972557f39055cee842f3da934ffea03b4bb79e4a1f9809aa30c