[INFO] cloning repository https://github.com/nwoeanhinnogaehr/flow-synth
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/nwoeanhinnogaehr/flow-synth" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnwoeanhinnogaehr%2Fflow-synth", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnwoeanhinnogaehr%2Fflow-synth'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2dc911b383ab53eeae1ebfae59c031aa360a349f
[INFO] checking nwoeanhinnogaehr/flow-synth against master#cfbc6d4cf1acbac5c025acf8ed68929caa551df3 for pr-75494-beta
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnwoeanhinnogaehr%2Fflow-synth" "/workspace/builds/worker-0/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/nwoeanhinnogaehr/flow-synth on toolchain cfbc6d4cf1acbac5c025acf8ed68929caa551df3
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cfbc6d4cf1acbac5c025acf8ed68929caa551df3" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/nwoeanhinnogaehr/flow-synth
[INFO] finished tweaking git repo https://github.com/nwoeanhinnogaehr/flow-synth
[INFO] tweaked toml for git repo https://github.com/nwoeanhinnogaehr/flow-synth written to /workspace/builds/worker-0/source/Cargo.toml
[INFO] crate git repo https://github.com/nwoeanhinnogaehr/flow-synth already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+cfbc6d4cf1acbac5c025acf8ed68929caa551df3" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
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[INFO] [stderr]   Downloaded gfx v0.18.1
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[INFO] [stderr]   Downloaded notify v4.0.12
[INFO] [stderr]   Downloaded crossbeam v0.7.1
[INFO] [stderr]   Downloaded futures-async-runtime-preview v0.2.3
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[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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+cfbc6d4cf1acbac5c025acf8ed68929caa551df3" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] e180a191344d12111946231ea6ff80d2934b17cd7bf0b23d43ce9a5e270fcd14
[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" "e180a191344d12111946231ea6ff80d2934b17cd7bf0b23d43ce9a5e270fcd14", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e180a191344d12111946231ea6ff80d2934b17cd7bf0b23d43ce9a5e270fcd14", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e180a191344d12111946231ea6ff80d2934b17cd7bf0b23d43ce9a5e270fcd14", kill_on_drop: false }`
[INFO] [stdout] e180a191344d12111946231ea6ff80d2934b17cd7bf0b23d43ce9a5e270fcd14
[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" "RUSTFLAGS=--cap-lints=forbid" "-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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+cfbc6d4cf1acbac5c025acf8ed68929caa551df3" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 8836dac035b75916da2f76ec328553b4dce19fd51da87772da211316365a8cd3
[INFO] running `Command { std: "docker" "start" "-a" "8836dac035b75916da2f76ec328553b4dce19fd51da87772da211316365a8cd3", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.58
[INFO] [stderr]    Compiling autocfg v0.1.4
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[INFO] [stderr]     Checking stable_deref_trait v1.1.1
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[INFO] [stderr]    Compiling num-bigint v0.2.2
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[INFO] [stderr]    Compiling serde v1.0.94
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[INFO] [stderr]     Checking futures-io-preview v0.2.2
[INFO] [stderr]    Compiling nfd v0.0.4
[INFO] [stderr]     Checking inotify v0.6.1
[INFO] [stderr]     Checking crossbeam-deque v0.7.1
[INFO] [stderr]     Checking osmesa-sys v0.1.2
[INFO] [stderr]     Checking jack v0.6.0
[INFO] [stderr]     Checking mio v0.6.19
[INFO] [stderr]     Checking futures-util-preview v0.2.2
[INFO] [stderr]     Checking crossbeam v0.7.1
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[INFO] [stderr]     Checking ordered-float v1.0.2
[INFO] [stderr]     Checking line_drawing v0.7.0
[INFO] [stderr]    Compiling libloading v0.5.1
[INFO] [stderr]    Compiling backtrace-sys v0.1.30
[INFO] [stderr]    Compiling gfx_gl v0.6.0
[INFO] [stderr]    Compiling glutin_egl_sys v0.1.3
[INFO] [stderr]    Compiling glutin_glx_sys v0.1.5
[INFO] [stderr]     Checking rusttype v0.7.7
[INFO] [stderr]     Checking twox-hash v1.4.1
[INFO] [stderr]     Checking mio-extras v2.0.5
[INFO] [stderr]     Checking parking_lot v0.7.1
[INFO] [stderr]     Checking ndarray v0.12.1
[INFO] [stderr]     Checking dlib v0.4.1
[INFO] [stderr]     Checking notify v4.0.12
[INFO] [stderr]     Checking wayland-sys v0.21.13
[INFO] [stderr]     Checking andrew v0.2.1
[INFO] [stderr]     Checking glyph_brush_layout v0.1.6
[INFO] [stderr]     Checking futures-executor-preview v0.2.2
[INFO] [stderr]     Checking backtrace v0.3.32
[INFO] [stderr]     Checking futures-stable-preview v0.2.3
[INFO] [stderr]     Checking glyph_brush v0.5.3
[INFO] [stderr]     Checking futures-async-runtime-preview v0.2.3
[INFO] [stderr]     Checking futures-preview v0.2.2
[INFO] [stderr]    Compiling wayland-client v0.21.13
[INFO] [stderr]    Compiling wayland-protocols v0.21.13
[INFO] [stderr]     Checking num v0.2.0
[INFO] [stderr]     Checking wayland-commons v0.21.13
[INFO] [stderr]    Compiling derivative v1.0.2
[INFO] [stderr]    Compiling serde_derive v1.0.94
[INFO] [stderr]     Checking smithay-client-toolkit v0.4.6
[INFO] [stderr]     Checking gfx_core v0.9.1
[INFO] [stderr]     Checking winit v0.19.1
[INFO] [stderr]     Checking glutin v0.21.0
[INFO] [stderr]     Checking gfx_device_gl v0.16.1
[INFO] [stderr]     Checking gfx v0.18.1
[INFO] [stderr]     Checking gfx_glyph v0.15.0
[INFO] [stderr]     Checking gfx_window_glutin v0.31.0
[INFO] [stderr]     Checking ron v0.5.1
[INFO] [stderr]     Checking flow-synth v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(plugin)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(const_fn)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(generators)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(generator_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(libc)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(drain_filter)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(nll)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(arbitrary_self_types)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/main.rs:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | #![feature(never_type)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/main.rs:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | #![feature(async_await)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/main.rs:12:1
[INFO] [stdout]    |
[INFO] [stdout] 12 | #![feature(atomic_min_max)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:1:1
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:2:1
[INFO] [stdout]   |
[INFO] [stdout] 2 | #![feature(plugin)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:3:1
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![feature(const_fn)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:4:1
[INFO] [stdout]   |
[INFO] [stdout] 4 | #![feature(generators)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:5:1
[INFO] [stdout]   |
[INFO] [stdout] 5 | #![feature(generator_trait)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:6:1
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![feature(libc)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:7:1
[INFO] [stdout]   |
[INFO] [stdout] 7 | #![feature(drain_filter)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(nll)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]  --> src/main.rs:9:1
[INFO] [stdout]   |
[INFO] [stdout] 9 | #![feature(arbitrary_self_types)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/main.rs:10:1
[INFO] [stdout]    |
[INFO] [stdout] 10 | #![feature(never_type)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/main.rs:11:1
[INFO] [stdout]    |
[INFO] [stdout] 11 | #![feature(async_await)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the beta release channel
[INFO] [stdout]   --> src/main.rs:12:1
[INFO] [stdout]    |
[INFO] [stdout] 12 | #![feature(atomic_min_max)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the feature `specialization` is incomplete and may not be safe to use and/or cause compiler crashes
[INFO] [stdout]  --> src/main.rs:1:12
[INFO] [stdout]   |
[INFO] [stdout] 1 | #![feature(specialization)]
[INFO] [stdout]   |            ^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(incomplete_features)]` on by default
[INFO] [stdout]   = note: see issue #31844 <https://github.com/rust-lang/rust/issues/31844> for more information
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 12 previous errors; 1 warning 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 `flow-synth`.
[INFO] [stdout] error: aborting due to 12 previous errors; 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[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" "8836dac035b75916da2f76ec328553b4dce19fd51da87772da211316365a8cd3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8836dac035b75916da2f76ec328553b4dce19fd51da87772da211316365a8cd3", kill_on_drop: false }`
[INFO] [stdout] 8836dac035b75916da2f76ec328553b4dce19fd51da87772da211316365a8cd3
