[INFO] cloning repository https://github.com/Xiulf/lowlang
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Xiulf/lowlang" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FXiulf%2Flowlang", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FXiulf%2Flowlang'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 632f747baf681d037c5d731b6b6e68967a83f207
[INFO] documenting Xiulf/lowlang against beta-2021-08-01 for beta-1.55-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FXiulf%2Flowlang" "/workspace/builds/worker-9/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-9/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Xiulf/lowlang on toolchain beta-2021-08-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Xiulf/lowlang
[INFO] finished tweaking git repo https://github.com/Xiulf/lowlang
[INFO] tweaked toml for git repo https://github.com/Xiulf/lowlang written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] crate git repo https://github.com/Xiulf/lowlang already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-08-01" "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] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded cranelift-module v0.68.0
[INFO] [stderr]   Downloaded cranelift-entity v0.68.0
[INFO] [stderr]   Downloaded cranelift-codegen-shared v0.68.0
[INFO] [stderr]   Downloaded anyhow v1.0.35
[INFO] [stderr]   Downloaded cranelift v0.68.0
[INFO] [stderr]   Downloaded cranelift-codegen v0.68.0
[INFO] [stderr]   Downloaded cranelift-frontend v0.68.0
[INFO] [stderr]   Downloaded cranelift-bforest v0.68.0
[INFO] [stderr]   Downloaded index_vec v0.1.2
[INFO] [stderr]   Downloaded cranelift-codegen-meta v0.68.0
[INFO] [stderr]   Downloaded cranelift-object v0.68.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] d103b2e834986e04168a6ffaead59e3feacaad484f15dc20054b57e298e4c3dd
[INFO] running `Command { std: "docker" "start" "-a" "d103b2e834986e04168a6ffaead59e3feacaad484f15dc20054b57e298e4c3dd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "d103b2e834986e04168a6ffaead59e3feacaad484f15dc20054b57e298e4c3dd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "d103b2e834986e04168a6ffaead59e3feacaad484f15dc20054b57e298e4c3dd", kill_on_drop: false }`
[INFO] [stdout] d103b2e834986e04168a6ffaead59e3feacaad484f15dc20054b57e298e4c3dd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-08-01" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a891792f40a3032924b20849b6a7570b437bba621fda20b2cd2f2d8539c3c5ae
[INFO] running `Command { std: "docker" "start" "-a" "a891792f40a3032924b20849b6a7570b437bba621fda20b2cd2f2d8539c3c5ae", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]    Compiling target-lexicon v0.11.1
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]     Checking linked-hash-map v0.5.4
[INFO] [stderr]     Checking index_vec v0.1.2
[INFO] [stderr]    Compiling libc v0.2.81
[INFO] [stderr]    Compiling syn v1.0.54
[INFO] [stderr]    Compiling log v0.4.11
[INFO] [stderr]    Compiling cranelift-entity v0.68.0
[INFO] [stderr]    Compiling cranelift-codegen-shared v0.68.0
[INFO] [stderr]    Compiling getrandom v0.1.15
[INFO] [stderr]    Compiling byteorder v1.3.4
[INFO] [stderr]     Checking rustc-hash v1.1.0
[INFO] [stderr]     Checking smallvec v1.5.1
[INFO] [stderr]     Checking ppv-lite86 v0.2.10
[INFO] [stderr]     Checking hashbrown v0.9.1
[INFO] [stderr]    Compiling anyhow v1.0.35
[INFO] [stderr]     Checking remove_dir_all v0.5.3
[INFO] [stderr]    Compiling indexmap v1.6.0
[INFO] [stderr]    Compiling quote v1.0.7
[INFO] [stderr]     Checking linked_hash_set v0.1.4
[INFO] [stderr]     Checking cranelift-bforest v0.68.0
[INFO] [stderr]    Compiling cranelift-codegen-meta v0.68.0
[INFO] [stderr]     Checking regalloc v0.0.31
[INFO] [stderr]     Checking ir v0.1.0 (/opt/rustwide/workdir/ir)
[INFO] [stderr]  Documenting ir v0.1.0 (/opt/rustwide/workdir/ir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> ir/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iterator_fold_self)]
[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 `ir`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   process didn't exit successfully: `rustdoc --edition=2018 --crate-type lib --crate-name ir ir/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 index_vec=/opt/rustwide/target/debug/deps/libindex_vec-3b01f0cc1b5900d4.rmeta --extern linked_hash_set=/opt/rustwide/target/debug/deps/liblinked_hash_set-17309ea33db55514.rmeta --extern target_lexicon=/opt/rustwide/target/debug/deps/libtarget_lexicon-ffdf6bd83fe29d02.rmeta --cap-lints=warn --crate-version 0.1.0` (exit status: 1)
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> ir/src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(iterator_fold_self)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0599]: no method named `fold_first` found for struct `Map` in the current scope
[INFO] [stdout]   --> ir/src/graph.rs:86:18
[INFO] [stdout]    |
[INFO] [stdout] 86 |                 .fold_first(|a, b| a.intersection(&b).copied().collect())
[INFO] [stdout]    |                  ^^^^^^^^^^ method not found in `Map<std::vec::IntoIter<Block>, [closure@ir/src/graph.rs:85:22: 85:68]>`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 2 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] Some errors have detailed explanations: E0554, E0599.
[INFO] [stdout] 
[INFO] [stdout] For more information about an error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "a891792f40a3032924b20849b6a7570b437bba621fda20b2cd2f2d8539c3c5ae", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a891792f40a3032924b20849b6a7570b437bba621fda20b2cd2f2d8539c3c5ae", kill_on_drop: false }`
[INFO] [stdout] a891792f40a3032924b20849b6a7570b437bba621fda20b2cd2f2d8539c3c5ae
