[INFO] cloning repository https://github.com/den-taku/matrix
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/den-taku/matrix" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fden-taku%2Fmatrix", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fden-taku%2Fmatrix'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 7db7d045aed1113903dc74b84d80cc7f64c5b3e4
[INFO] documenting den-taku/matrix 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%2Fden-taku%2Fmatrix" "/workspace/builds/worker-31/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-31/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/den-taku/matrix 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/den-taku/matrix
[INFO] finished tweaking git repo https://github.com/den-taku/matrix
[INFO] tweaked toml for git repo https://github.com/den-taku/matrix written to /workspace/builds/worker-31/source/Cargo.toml
[INFO] crate git repo https://github.com/den-taku/matrix 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]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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] 54ca443c89016ac2f1b989c25b2bc3c8f922a71d861d3a50c56cb8da038ae6b1
[INFO] running `Command { std: "docker" "start" "-a" "54ca443c89016ac2f1b989c25b2bc3c8f922a71d861d3a50c56cb8da038ae6b1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "54ca443c89016ac2f1b989c25b2bc3c8f922a71d861d3a50c56cb8da038ae6b1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "54ca443c89016ac2f1b989c25b2bc3c8f922a71d861d3a50c56cb8da038ae6b1", kill_on_drop: false }`
[INFO] [stdout] 54ca443c89016ac2f1b989c25b2bc3c8f922a71d861d3a50c56cb8da038ae6b1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-31/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] 72d6abc7c519bd79981376c4dbdd9afb74fe97045ee7951ac355393fdab0c30d
[INFO] running `Command { std: "docker" "start" "-a" "72d6abc7c519bd79981376c4dbdd9afb74fe97045ee7951ac355393fdab0c30d", kill_on_drop: false }`
[INFO] [stderr]    Compiling autocfg v1.1.0
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.4.3
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]     Checking num-complex v0.4.0
[INFO] [stderr]     Checking num v0.4.0
[INFO] [stderr]  Documenting dntk-matrix v0.1.2 (/opt/rustwide/workdir)
[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(generic_const_exprs)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: Compilation failed, aborting rustdoc
[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 `dntk-matrix`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2021 --crate-type lib --crate-name dntk_matrix src/lib.rs -o /opt/rustwide/target/doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --document-private-items -C metadata=cbdb75d22b0f1bef -L dependency=/opt/rustwide/target/debug/deps --extern num=/opt/rustwide/target/debug/deps/libnum-e6fe91b9e9d369c9.rmeta --cap-lints=warn --crate-version 0.1.2` (exit status: 1)
[INFO] running `Command { std: "docker" "inspect" "72d6abc7c519bd79981376c4dbdd9afb74fe97045ee7951ac355393fdab0c30d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "72d6abc7c519bd79981376c4dbdd9afb74fe97045ee7951ac355393fdab0c30d", kill_on_drop: false }`
[INFO] [stdout] 72d6abc7c519bd79981376c4dbdd9afb74fe97045ee7951ac355393fdab0c30d