[INFO] fetching crate libsvm 0.2.1...
[INFO] documenting libsvm-0.2.1 against 1.47.0 for beta-1.48-rustdoc-1
[INFO] extracting crate libsvm 0.2.1 into /workspace/builds/worker-0/source
[INFO] validating manifest of crates.io crate libsvm 0.2.1 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate libsvm 0.2.1
[INFO] finished tweaking crates.io crate libsvm 0.2.1
[INFO] tweaked toml for crates.io crate libsvm 0.2.1 written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 05f8a214b0fc3ce9b9653fb64d7eb24d56a77d53274521d335b92aa7bbbc9dc1
[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" "05f8a214b0fc3ce9b9653fb64d7eb24d56a77d53274521d335b92aa7bbbc9dc1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "05f8a214b0fc3ce9b9653fb64d7eb24d56a77d53274521d335b92aa7bbbc9dc1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "05f8a214b0fc3ce9b9653fb64d7eb24d56a77d53274521d335b92aa7bbbc9dc1", kill_on_drop: false }`
[INFO] [stdout] 05f8a214b0fc3ce9b9653fb64d7eb24d56a77d53274521d335b92aa7bbbc9dc1
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0/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" "+1.47.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 26d227840a4f4705a1b4f01c537202245dd38944eb5956d547f9b23f544d2ab1
[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" "26d227840a4f4705a1b4f01c537202245dd38944eb5956d547f9b23f544d2ab1", kill_on_drop: false }`
[INFO] [stderr]    Compiling libsvm-sys v3.24.0
[INFO] [stderr]    Compiling ctor v0.1.16
[INFO] [stderr]    Compiling num-derive v0.3.2
[INFO] [stderr]     Checking failure v0.1.8
[INFO] [stderr]  Documenting libsvm v0.2.1 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(const_generics)]
[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:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(fixed_size_array)]
[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] [stderr] error: Could not document `libsvm`.
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name libsvm 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 ctor=/opt/rustwide/target/debug/deps/libctor-bce848e86e4fd1e3.so --extern failure=/opt/rustwide/target/debug/deps/libfailure-780a7caf0efff8b2.rmeta --extern libsvm_sys=/opt/rustwide/target/debug/deps/liblibsvm_sys-ceab4d2330757c7c.rmeta --extern num=/opt/rustwide/target/debug/deps/libnum-da2da60ac29d82d9.rmeta --extern num_derive=/opt/rustwide/target/debug/deps/libnum_derive-cffed362aa773643.so --extern num_traits=/opt/rustwide/target/debug/deps/libnum_traits-75d0567c7bbde356.rmeta --cap-lints=warn --crate-version 0.2.1` (exit code: 1)
[INFO] running `Command { std: "docker" "inspect" "26d227840a4f4705a1b4f01c537202245dd38944eb5956d547f9b23f544d2ab1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "26d227840a4f4705a1b4f01c537202245dd38944eb5956d547f9b23f544d2ab1", kill_on_drop: false }`
[INFO] [stdout] 26d227840a4f4705a1b4f01c537202245dd38944eb5956d547f9b23f544d2ab1
