[INFO] updating cached repository https://github.com/system76/dbg2
[INFO] running `"git" "-c" "credential.helper=" "-c" "credential.helper=/big/crater/work/cargo-home/bin/git-credential-null" "-c" "remote.origin.fetch=refs/heads/*:refs/heads/*" "fetch" "origin" "--force" "--prune"`
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 5feec2677c03618a309ea54250263a87bf33957d
[INFO] testing system76/dbg2 against 1.38.0 for beta-1.39-1
[INFO] running `"git" "clone" "work/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsystem76%2Fdbg2" "work/builds/worker-3/source"`
[INFO] [stderr] Cloning into 'work/builds/worker-3/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/system76/dbg2 on toolchain 1.38.0
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking git repo https://github.com/system76/dbg2
[INFO] finished tweaking git repo https://github.com/system76/dbg2
[INFO] tweaked toml for git repo https://github.com/system76/dbg2 written to work/builds/worker-3/source/Cargo.toml
[INFO] crate git repo https://github.com/system76/dbg2 already has a lockfile, it will not be regenerated
[INFO] running `"/big/crater/work/cargo-home/bin/cargo" "+1.38.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"docker" "create" "-v" "/big/crater/work/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/big/crater/work/builds/worker-3/source:/opt/rustwide/workdir:ro,Z" "-v" "/big/crater/work/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/big/crater/work/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "MAP_USER_ID=1000" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+1.38.0" "build" "--frozen"`
[INFO] [stdout] ed5fb058e492db8fd35750aa518fbf63aab1509c4b3bbecb0bb9739925518cad
[INFO] running `"docker" "start" "-a" "ed5fb058e492db8fd35750aa518fbf63aab1509c4b3bbecb0bb9739925518cad"`
[INFO] [stderr]    Compiling redox_hwio v0.1.0
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/redox_hwio-0.1.0/src/lib.rs:2:63
[INFO] [stderr]   |
[INFO] [stderr] 2 | #![cfg_attr(any(target_arch = "x86", target_arch = "x86_64"), feature(asm))]
[INFO] [stderr]   |                                                               ^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/redox_hwio-0.1.0/src/lib.rs:3:1
[INFO] [stderr]   |
[INFO] [stderr] 3 | #![feature(const_fn)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stderr]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/redox_hwio-0.1.0/src/lib.rs:4:1
[INFO] [stderr]   |
[INFO] [stderr] 4 | #![feature(core_intrinsics)]
[INFO] [stderr]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to 3 previous errors
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0554`.
[INFO] [stderr] error: Could not compile `redox_hwio`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "ed5fb058e492db8fd35750aa518fbf63aab1509c4b3bbecb0bb9739925518cad"`
[INFO] running `"docker" "rm" "-f" "ed5fb058e492db8fd35750aa518fbf63aab1509c4b3bbecb0bb9739925518cad"`
[INFO] [stdout] ed5fb058e492db8fd35750aa518fbf63aab1509c4b3bbecb0bb9739925518cad