[INFO] fetching crate dachshund 0.1.2...
[INFO] testing dachshund-0.1.2 against 1.47.0 for beta-1.48-1
[INFO] extracting crate dachshund 0.1.2 into /workspace/builds/worker-14/source
[INFO] validating manifest of crates.io crate dachshund 0.1.2 on toolchain 1.47.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate dachshund 0.1.2
[INFO] finished tweaking crates.io crate dachshund 0.1.2
[INFO] tweaked toml for crates.io crate dachshund 0.1.2 written to /workspace/builds/worker-14/source/Cargo.toml
[INFO] crate crates.io crate dachshund 0.1.2 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 01a0218e1313c620dc6d28a7fcb04c2c3b3074c5281753610842d82b1e808342
[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" "01a0218e1313c620dc6d28a7fcb04c2c3b3074c5281753610842d82b1e808342", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "01a0218e1313c620dc6d28a7fcb04c2c3b3074c5281753610842d82b1e808342", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "01a0218e1313c620dc6d28a7fcb04c2c3b3074c5281753610842d82b1e808342", kill_on_drop: false }`
[INFO] [stdout] 01a0218e1313c620dc6d28a7fcb04c2c3b3074c5281753610842d82b1e808342
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-14/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:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.47.0" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a620d6bf70688d5d22914379c61bde5dd83e2d890917576db85230a004edfcba
[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" "a620d6bf70688d5d22914379c61bde5dd83e2d890917576db85230a004edfcba", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.38
[INFO] [stderr]    Compiling serde v1.0.114
[INFO] [stderr]    Compiling num-traits v0.2.12
[INFO] [stderr]    Compiling num-complex v0.2.4
[INFO] [stderr]    Compiling num-rational v0.2.4
[INFO] [stderr]    Compiling paste-impl v0.1.18
[INFO] [stderr]    Compiling rand_os v0.1.3
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling rand_distr v0.2.2
[INFO] [stderr]    Compiling rayon-core v1.7.1
[INFO] [stderr]    Compiling clap v2.33.2
[INFO] [stderr]    Compiling rand v0.6.5
[INFO] [stderr]    Compiling rayon v1.3.1
[INFO] [stderr]    Compiling paste v0.1.18
[INFO] [stderr]    Compiling num-integer v0.1.43
[INFO] [stderr]    Compiling approx v0.3.2
[INFO] [stderr]    Compiling simba v0.1.5
[INFO] [stderr]    Compiling nalgebra v0.21.1
[INFO] [stderr]    Compiling thiserror-impl v1.0.20
[INFO] [stderr]    Compiling thiserror v1.0.20
[INFO] [stderr]    Compiling serde_json v1.0.57
[INFO] [stderr]    Compiling dachshund v0.1.2 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:8:1
[INFO] [stdout]   |
[INFO] [stdout] 8 | #![feature(map_first_last)]
[INFO] [stdout]   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `dachshund`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "a620d6bf70688d5d22914379c61bde5dd83e2d890917576db85230a004edfcba", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a620d6bf70688d5d22914379c61bde5dd83e2d890917576db85230a004edfcba", kill_on_drop: false }`
[INFO] [stdout] a620d6bf70688d5d22914379c61bde5dd83e2d890917576db85230a004edfcba
