[INFO] cloning repository https://github.com/museun/md2
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/museun/md2" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmuseun%2Fmd2", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmuseun%2Fmd2'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 908aab10308e70b2b6c6288761ac600b37e60417
[INFO] documenting museun/md2 against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmuseun%2Fmd2" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/museun/md2 on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/museun/md2
[INFO] finished tweaking git repo https://github.com/museun/md2
[INFO] tweaked toml for git repo https://github.com/museun/md2 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/museun/md2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 8455aae90247777a9fd95e2c9d3a7e4eaddc450eceb52a69e3ad95cd3cf14957
[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" "8455aae90247777a9fd95e2c9d3a7e4eaddc450eceb52a69e3ad95cd3cf14957", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "8455aae90247777a9fd95e2c9d3a7e4eaddc450eceb52a69e3ad95cd3cf14957", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8455aae90247777a9fd95e2c9d3a7e4eaddc450eceb52a69e3ad95cd3cf14957", kill_on_drop: false }`
[INFO] [stdout] 8455aae90247777a9fd95e2c9d3a7e4eaddc450eceb52a69e3ad95cd3cf14957
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 31092a83dba75586b5a564927d415f1ec9fdc86062c4e4f1e5f7cc82171a9f51
[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" "31092a83dba75586b5a564927d415f1ec9fdc86062c4e4f1e5f7cc82171a9f51", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling regex v1.0.2
[INFO] [stderr]     Checking termcolor v1.0.1
[INFO] [stderr]     Checking regex-syntax v0.6.2
[INFO] [stderr]     Checking memchr v2.0.1
[INFO] [stderr]     Checking atty v0.2.11
[INFO] [stderr]     Checking thread_local v0.3.5
[INFO] [stderr]     Checking aho-corasick v0.6.6
[INFO] [stderr]     Checking nom v4.0.0
[INFO] [stderr]     Checking env_logger v0.5.12
[INFO] [stderr]     Checking md2 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]  Documenting md2 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(tool_attributes)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(concat_idents)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(tool_attributes)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: Could not document `md2`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --crate-type lib --crate-name md2 src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern byteorder=/opt/rustwide/target/debug/deps/libbyteorder-b22a46763d4a83c3.rmeta --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-00b980e9a1a3149c.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-77fbf2c8125b70b6.rmeta --extern nom=/opt/rustwide/target/debug/deps/libnom-351a93e25872fc7d.rmeta --cap-lints=warn` (exit code: 1)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(concat_idents)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around assigned value
[INFO] [stdout]   --> src/header.rs:54:30
[INFO] [stdout]    |
[INFO] [stdout] 54 |           const IDENT: int_t = ((('2' as int_t) << 24)
[INFO] [stdout]    |  ______________________________^
[INFO] [stdout] 55 | |             + (('P' as int_t) << 16)
[INFO] [stdout] 56 | |             + (('D' as int_t) << 8)
[INFO] [stdout] 57 | |             + 'I' as int_t);
[INFO] [stdout]    | |___________________________^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_parens)]` on by default
[INFO] [stdout] help: remove these parentheses
[INFO] [stdout]    |
[INFO] [stdout] 54 |         const IDENT: int_t = (('2' as int_t) << 24)
[INFO] [stdout] 55 |             + (('P' as int_t) << 16)
[INFO] [stdout] 56 |             + (('D' as int_t) << 8)
[INFO] [stdout] 57 |             + 'I' as int_t;
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "31092a83dba75586b5a564927d415f1ec9fdc86062c4e4f1e5f7cc82171a9f51", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "31092a83dba75586b5a564927d415f1ec9fdc86062c4e4f1e5f7cc82171a9f51", kill_on_drop: false }`
[INFO] [stdout] 31092a83dba75586b5a564927d415f1ec9fdc86062c4e4f1e5f7cc82171a9f51