[INFO] fetching crate stream_buffer 0.2.0...
[INFO] testing stream_buffer-0.2.0 against beta-2021-01-01 for beta-1.50-1
[INFO] extracting crate stream_buffer 0.2.0 into /workspace/builds/worker-7/source
[INFO] validating manifest of crates.io crate stream_buffer 0.2.0 on toolchain beta-2021-01-01
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate stream_buffer 0.2.0
[INFO] finished tweaking crates.io crate stream_buffer 0.2.0
[INFO] tweaked toml for crates.io crate stream_buffer 0.2.0 written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate crates.io crate stream_buffer 0.2.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta-2021-01-01" "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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 365db850059c40bff248f0ac2214eda63cc6593f784b0f670eb3aa74048310d3
[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" "365db850059c40bff248f0ac2214eda63cc6593f784b0f670eb3aa74048310d3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "365db850059c40bff248f0ac2214eda63cc6593f784b0f670eb3aa74048310d3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "365db850059c40bff248f0ac2214eda63cc6593f784b0f670eb3aa74048310d3", kill_on_drop: false }`
[INFO] [stdout] 365db850059c40bff248f0ac2214eda63cc6593f784b0f670eb3aa74048310d3
[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" "RUSTFLAGS=--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:b8eeb62f26c39b23691079a6cb6de528d8e88b4d71a8f6b1d30f8ba7d9c16de9" "/opt/rustwide/cargo-home/bin/cargo" "+beta-2021-01-01" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 299d9778c93edc5b8195c0ce046d19e90f5809d30f74e45e880480662a236646
[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" "299d9778c93edc5b8195c0ce046d19e90f5809d30f74e45e880480662a236646", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.74
[INFO] [stderr]    Compiling cfg-if v0.1.10
[INFO] [stderr]    Compiling ppv-lite86 v0.2.8
[INFO] [stderr]    Compiling remove_dir_all v0.5.3
[INFO] [stderr]    Compiling either v1.6.0
[INFO] [stderr]    Compiling getrandom v0.1.14
[INFO] [stderr]    Compiling itertools v0.9.0
[INFO] [stderr]    Compiling rand_core v0.5.1
[INFO] [stderr]    Compiling rand_chacha v0.2.2
[INFO] [stderr]    Compiling rand v0.7.3
[INFO] [stderr]    Compiling tempfile v3.1.0
[INFO] [stderr]    Compiling stream_buffer v0.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(type_alias_impl_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(trait_alias)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/lib.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(extend_one)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::io::BufWriter`
[INFO] [stdout]  --> src/buf.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 | use std::io::BufWriter;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Into`, `TryInto`
[INFO] [stdout]  --> src/chunk.rs:6:20
[INFO] [stdout]   |
[INFO] [stdout] 6 | use std::convert::{TryInto, Into};
[INFO] [stdout]   |                    ^^^^^^^  ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `IntoStream`
[INFO] [stdout]  --> src/chunk.rs:3:40
[INFO] [stdout]   |
[INFO] [stdout] 3 | use super::types::{FileLike, BufResult,IntoStream, IterStream};
[INFO] [stdout]   |                                        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Read`
[INFO] [stdout]  --> src/chunk.rs:5:15
[INFO] [stdout]   |
[INFO] [stdout] 5 | use std::io::{Read, SeekFrom};
[INFO] [stdout]   |               ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors; 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `stream_buffer`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "299d9778c93edc5b8195c0ce046d19e90f5809d30f74e45e880480662a236646", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "299d9778c93edc5b8195c0ce046d19e90f5809d30f74e45e880480662a236646", kill_on_drop: false }`
[INFO] [stdout] 299d9778c93edc5b8195c0ce046d19e90f5809d30f74e45e880480662a236646