[INFO] fetching crate unix-fifo-async 0.0.3...
[INFO] testing unix-fifo-async-0.0.3 against 1.90.0 for beta-1.91-3
[INFO] extracting crate unix-fifo-async 0.0.3 into /workspace/builds/worker-6-tc1/source
[INFO] started tweaking crates.io crate unix-fifo-async 0.0.3
[INFO] finished tweaking crates.io crate unix-fifo-async 0.0.3
[INFO] tweaked toml for crates.io crate unix-fifo-async 0.0.3 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate unix-fifo-async 0.0.3 on toolchain 1.90.0
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate unix-fifo-async 0.0.3 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+1.90.0" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded bitflags v1.1.0
[INFO] [stderr]   Downloaded cfg-if v0.1.9
[INFO] [stderr]   Downloaded pin-utils v0.1.0-alpha.4
[INFO] [stderr]   Downloaded num_cpus v1.10.1
[INFO] [stderr]   Downloaded mio v0.6.19
[INFO] [stderr]   Downloaded futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded async-task v1.0.0
[INFO] [stderr]   Downloaded futures-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded async-std v0.99.3
[INFO] [stderr]   Downloaded cc v1.0.40
[INFO] [stderr]   Downloaded nix v0.15.0
[INFO] [stderr]   Downloaded crossbeam-channel v0.3.9
[INFO] [stderr]   Downloaded crossbeam-utils v0.6.6
[INFO] [stderr]   Downloaded futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded libc v0.2.62
[INFO] [stderr]   Downloaded futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded futures-timer v0.3.0
[INFO] [stderr]   Downloaded lazy_static v1.3.0
[INFO] [stderr]   Downloaded memchr v2.2.1
[INFO] [stderr]   Downloaded iovec v0.1.2
[INFO] [stderr]   Downloaded futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]   Downloaded winapi v0.3.7
[INFO] [stderr]   Downloaded futures-sink-preview v0.3.0-alpha.18
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0669b2dd673031f67cd73d7127ee2cb83b3d296e6f9a4380f6b675e980395b09
[INFO] running `Command { std: "docker" "start" "-a" "0669b2dd673031f67cd73d7127ee2cb83b3d296e6f9a4380f6b675e980395b09", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0669b2dd673031f67cd73d7127ee2cb83b3d296e6f9a4380f6b675e980395b09", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0669b2dd673031f67cd73d7127ee2cb83b3d296e6f9a4380f6b675e980395b09", kill_on_drop: false }`
[INFO] [stdout] 0669b2dd673031f67cd73d7127ee2cb83b3d296e6f9a4380f6b675e980395b09
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/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" "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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+1.90.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 368aa410f73a525b8f2471c5c8ee7844f0524205792bc5b4e82f9aab5d2cd7b0
[INFO] running `Command { std: "docker" "start" "-a" "368aa410f73a525b8f2471c5c8ee7844f0524205792bc5b4e82f9aab5d2cd7b0", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.62
[INFO] [stderr]    Compiling cfg-if v0.1.9
[INFO] [stderr]    Compiling slab v0.4.2
[INFO] [stderr]    Compiling memchr v2.2.1
[INFO] [stderr]    Compiling futures-core-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling pin-utils v0.1.0-alpha.4
[INFO] [stderr]    Compiling log v0.4.8
[INFO] [stderr]    Compiling futures-io-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling lazy_static v1.3.0
[INFO] [stderr]    Compiling bitflags v1.1.0
[INFO] [stderr]    Compiling nix v0.15.0
[INFO] [stderr]    Compiling void v1.0.2
[INFO] [stderr]    Compiling crossbeam-utils v0.6.6
[INFO] [stderr]    Compiling futures-sink-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-channel-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling crossbeam-channel v0.3.9
[INFO] [stderr]    Compiling async-task v1.0.0
[INFO] [stderr]    Compiling futures-util-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling num_cpus v1.10.1
[INFO] [stderr]    Compiling net2 v0.2.33
[INFO] [stderr]    Compiling iovec v0.1.2
[INFO] [stderr]    Compiling mio v0.6.19
[INFO] [stderr]    Compiling mio-uds v0.6.7
[INFO] [stderr]    Compiling futures-executor-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-preview v0.3.0-alpha.18
[INFO] [stderr]    Compiling futures-timer v0.3.0
[INFO] [stderr]    Compiling async-std v0.99.3
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/async-std-0.99.3/src/lib.rs:30:1
[INFO] [stdout]    |
[INFO] [stdout] 30 | #![feature(async_await)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^ help: remove the attribute
[INFO] [stdout]    |
[INFO] [stdout]    = help: the feature `async_await` has been stable since `1.39.0` and no longer requires an attribute to enable
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `async-std` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "368aa410f73a525b8f2471c5c8ee7844f0524205792bc5b4e82f9aab5d2cd7b0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "368aa410f73a525b8f2471c5c8ee7844f0524205792bc5b4e82f9aab5d2cd7b0", kill_on_drop: false }`
[INFO] [stdout] 368aa410f73a525b8f2471c5c8ee7844f0524205792bc5b4e82f9aab5d2cd7b0
