[INFO] fetching crate buttons 0.3.1...
[INFO] checking buttons-0.3.1 against master#4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5 for pr-81174
[INFO] extracting crate buttons 0.3.1 into /workspace/builds/worker-12/source
[INFO] validating manifest of crates.io crate buttons 0.3.1 on toolchain 4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate buttons 0.3.1
[INFO] finished tweaking crates.io crate buttons 0.3.1
[INFO] tweaked toml for crates.io crate buttons 0.3.1 written to /workspace/builds/worker-12/source/Cargo.toml
[INFO] crate crates.io crate buttons 0.3.1 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f99e809f34745f8ae7fc73f2384b2c0de2d075e57ee44de40e9ea484fff840dd
[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" "f99e809f34745f8ae7fc73f2384b2c0de2d075e57ee44de40e9ea484fff840dd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f99e809f34745f8ae7fc73f2384b2c0de2d075e57ee44de40e9ea484fff840dd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f99e809f34745f8ae7fc73f2384b2c0de2d075e57ee44de40e9ea484fff840dd", kill_on_drop: false }`
[INFO] [stdout] f99e809f34745f8ae7fc73f2384b2c0de2d075e57ee44de40e9ea484fff840dd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-12/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@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+4d0dd02ee07bddad9136f95c9f7846ebf3eb3fc5" "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] 019d2f8d9847bdc50c0523057d6cce12e2cc111a8d3d43a210dd67057a421f56
[INFO] running `Command { std: "docker" "start" "-a" "019d2f8d9847bdc50c0523057d6cce12e2cc111a8d3d43a210dd67057a421f56", kill_on_drop: false }`
[INFO] [stderr]     Checking buttons v0.3.1 (/opt/rustwide/workdir)
[INFO] [stderr] error: could not compile `buttons`
[INFO] [stdout] error[E0601]: `main` function not found in crate `winit`
[INFO] [stdout]   --> examples/winit.rs:1:1
[INFO] [stdout]    |
[INFO] [stdout] 1  | / #![cfg(feature = "winit-support")]
[INFO] [stdout] 2  | |
[INFO] [stdout] 3  | | use winit::{
[INFO] [stdout] 4  | |     event::*,
[INFO] [stdout] ...  |
[INFO] [stdout] 54 | |     });
[INFO] [stdout] 55 | | }
[INFO] [stdout]    | |_^ consider adding a `main` function to `examples/winit.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] running `Command { std: "docker" "inspect" "019d2f8d9847bdc50c0523057d6cce12e2cc111a8d3d43a210dd67057a421f56", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "019d2f8d9847bdc50c0523057d6cce12e2cc111a8d3d43a210dd67057a421f56", kill_on_drop: false }`
[INFO] [stdout] 019d2f8d9847bdc50c0523057d6cce12e2cc111a8d3d43a210dd67057a421f56