[INFO] fetching crate qemu-exit 1.0.2...
[INFO] testing qemu-exit-1.0.2 against 1.49.0 for beta-1.50-1
[INFO] extracting crate qemu-exit 1.0.2 into /workspace/builds/worker-3/source
[INFO] validating manifest of crates.io crate qemu-exit 1.0.2 on toolchain 1.49.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-3/source/.cargo/config
[INFO] started tweaking crates.io crate qemu-exit 1.0.2
[INFO] removed 0 missing tests
[INFO] finished tweaking crates.io crate qemu-exit 1.0.2
[INFO] tweaked toml for crates.io crate qemu-exit 1.0.2 written to /workspace/builds/worker-3/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.49.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.49.0" "metadata" "--no-deps" "--format-version=1", 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] e1446335a8433168560e9794588a8cfc452f99af2cfcf964256671f945ea80b4
[INFO] running `Command { std: "docker" "start" "-a" "e1446335a8433168560e9794588a8cfc452f99af2cfcf964256671f945ea80b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e1446335a8433168560e9794588a8cfc452f99af2cfcf964256671f945ea80b4", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e1446335a8433168560e9794588a8cfc452f99af2cfcf964256671f945ea80b4", kill_on_drop: false }`
[INFO] [stdout] e1446335a8433168560e9794588a8cfc452f99af2cfcf964256671f945ea80b4
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-3/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" "+1.49.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1654a24f89209bf25cd2f6fd970ae09018b987a18f900ccc46ae9954968abb9f
[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" "1654a24f89209bf25cd2f6fd970ae09018b987a18f900ccc46ae9954968abb9f", kill_on_drop: false }`
[INFO] [stderr]    Compiling qemu-exit v1.0.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:73:1
[INFO] [stdout]    |
[INFO] [stdout] 73 | #![feature(asm)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:74:1
[INFO] [stdout]    |
[INFO] [stdout] 74 | #![feature(const_fn)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:75:1
[INFO] [stdout]    |
[INFO] [stdout] 75 | #![feature(const_panic)]
[INFO] [stdout]    | ^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 3 previous errors
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `qemu-exit`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "1654a24f89209bf25cd2f6fd970ae09018b987a18f900ccc46ae9954968abb9f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1654a24f89209bf25cd2f6fd970ae09018b987a18f900ccc46ae9954968abb9f", kill_on_drop: false }`
[INFO] [stdout] 1654a24f89209bf25cd2f6fd970ae09018b987a18f900ccc46ae9954968abb9f