[INFO] cloning repository https://github.com/ldm0/ffgen
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/ldm0/ffgen" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fldm0%2Fffgen", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fldm0%2Fffgen'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 23638bbda1b8104ac0f8692ebda42c679dc9d5bb
[INFO] documenting ldm0/ffgen 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%2Fldm0%2Fffgen" "/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/ldm0/ffgen 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/ldm0/ffgen
[INFO] finished tweaking git repo https://github.com/ldm0/ffgen
[INFO] tweaked toml for git repo https://github.com/ldm0/ffgen written to /workspace/builds/worker-6/source/Cargo.toml
[INFO] crate git repo https://github.com/ldm0/ffgen 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-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" "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] 6dbbf164b4e4baf4932b6f2672d2a22bf017ecc6fda33a5f536dcb8e10a812ea
[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" "6dbbf164b4e4baf4932b6f2672d2a22bf017ecc6fda33a5f536dcb8e10a812ea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6dbbf164b4e4baf4932b6f2672d2a22bf017ecc6fda33a5f536dcb8e10a812ea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6dbbf164b4e4baf4932b6f2672d2a22bf017ecc6fda33a5f536dcb8e10a812ea", kill_on_drop: false }`
[INFO] [stdout] 6dbbf164b4e4baf4932b6f2672d2a22bf017ecc6fda33a5f536dcb8e10a812ea
[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" "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] d6bf3f917b919d9dccbaba5f7748bd00a9974ef7984dcc86d1bcce84f572255d
[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" "d6bf3f917b919d9dccbaba5f7748bd00a9974ef7984dcc86d1bcce84f572255d", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.19
[INFO] [stderr]    Compiling libc v0.2.73
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking env_logger v0.7.1
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]    Compiling clang-sys v0.29.3
[INFO] [stderr]    Compiling which v3.1.1
[INFO] [stderr]    Compiling num_cpus v1.13.0
[INFO] [stderr]    Compiling clap v2.33.1
[INFO] [stderr]    Compiling bindgen v0.54.1
[INFO] [stderr]    Compiling rusty_ffmpeg v0.2.5
[INFO] [stderr]  Documenting ffgen v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/main.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(raw_ref_op)]
[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:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(exclusive_range_pattern)]
[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:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(half_open_range_patterns)]
[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:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(ptr_offset_from)]
[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:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(bool_to_option)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 6 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 `ffgen`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type bin --crate-name ffgen src/main.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi --document-private-items -L dependency=/opt/rustwide/target/debug/deps --extern bitflags=/opt/rustwide/target/debug/deps/libbitflags-b7cb6f2855b37747.rmeta --extern env_logger=/opt/rustwide/target/debug/deps/libenv_logger-1de9e51fa88716a7.rmeta --extern libc=/opt/rustwide/target/debug/deps/liblibc-c3bd1cb21e99f2f0.rmeta --extern log=/opt/rustwide/target/debug/deps/liblog-958bf2a074a4960f.rmeta --extern memoffset=/opt/rustwide/target/debug/deps/libmemoffset-943b68e1492a25f8.rmeta --extern once_cell=/opt/rustwide/target/debug/deps/libonce_cell-67de5f6a6498d9d2.rmeta --extern rusty_ffmpeg=/opt/rustwide/target/debug/deps/librusty_ffmpeg-616b44c0c6c9ffad.rmeta --cap-lints=warn` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "d6bf3f917b919d9dccbaba5f7748bd00a9974ef7984dcc86d1bcce84f572255d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d6bf3f917b919d9dccbaba5f7748bd00a9974ef7984dcc86d1bcce84f572255d", kill_on_drop: false }`
[INFO] [stdout] d6bf3f917b919d9dccbaba5f7748bd00a9974ef7984dcc86d1bcce84f572255d