[INFO] fetching crate loader-rs 0.7.0...
[INFO] testing loader-rs-0.7.0 against 1.47.0 for beta-1.48-1
[INFO] extracting crate loader-rs 0.7.0 into /workspace/builds/worker-8/source
[INFO] validating manifest of crates.io crate loader-rs 0.7.0 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 loader-rs 0.7.0
[INFO] finished tweaking crates.io crate loader-rs 0.7.0
[INFO] tweaked toml for crates.io crate loader-rs 0.7.0 written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.47.0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[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-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] 9fdde7607499d4ba002333b6fb14493a5c0690f1bf036c63eabdcf9f15f796be
[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" "9fdde7607499d4ba002333b6fb14493a5c0690f1bf036c63eabdcf9f15f796be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "9fdde7607499d4ba002333b6fb14493a5c0690f1bf036c63eabdcf9f15f796be", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "9fdde7607499d4ba002333b6fb14493a5c0690f1bf036c63eabdcf9f15f796be", kill_on_drop: false }`
[INFO] [stdout] 9fdde7607499d4ba002333b6fb14493a5c0690f1bf036c63eabdcf9f15f796be
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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] 0a876fe826691282229df27e35e3a332ed6ace04eb9265d8df83ab67e381fb00
[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" "0a876fe826691282229df27e35e3a332ed6ace04eb9265d8df83ab67e381fb00", kill_on_drop: false }`
[INFO] [stderr]    Compiling syn v1.0.44
[INFO] [stderr]    Compiling futures-core v0.3.6
[INFO] [stderr]    Compiling pin-project-lite v0.1.10
[INFO] [stderr]    Compiling pin-project-internal v0.4.27
[INFO] [stderr]    Compiling once_cell v1.4.1
[INFO] [stderr]    Compiling openssl v0.10.30
[INFO] [stderr]    Compiling ident_case v1.0.1
[INFO] [stderr]    Compiling crc32fast v1.2.0
[INFO] [stderr]    Compiling strsim v0.9.3
[INFO] [stderr]    Compiling futures-io v0.3.6
[INFO] [stderr]    Compiling futures-sink v0.3.6
[INFO] [stderr]    Compiling native-tls v0.2.4
[INFO] [stderr]    Compiling openssl-probe v0.1.2
[INFO] [stderr]    Compiling adler v0.2.3
[INFO] [stderr]    Compiling try-lock v0.2.3
[INFO] [stderr]    Compiling tower-service v0.3.0
[INFO] [stderr]    Compiling encoding_rs v0.8.24
[INFO] [stderr]    Compiling event-listener v2.5.1
[INFO] [stderr]    Compiling httpdate v0.3.2
[INFO] [stderr]    Compiling dtoa v0.4.6
[INFO] [stderr]    Compiling mime v0.3.16
[INFO] [stderr]    Compiling base64 v0.12.3
[INFO] [stderr]    Compiling ipnet v2.3.0
[INFO] [stderr]    Compiling strum v0.19.5
[INFO] [stderr]    Compiling instant v0.1.7
[INFO] [stderr]    Compiling miniz_oxide v0.4.3
[INFO] [stderr]    Compiling openssl-sys v0.9.58
[INFO] [stderr]    Compiling unicase v2.6.0
[INFO] [stderr]    Compiling tracing-core v0.1.17
[INFO] [stderr]    Compiling futures-channel v0.3.6
[INFO] [stderr]    Compiling async-mutex v1.4.0
[INFO] [stderr]    Compiling futures-task v0.3.6
[INFO] [stderr]    Compiling lock_api v0.4.1
[INFO] [stderr]    Compiling http-body v0.3.1
[INFO] [stderr]    Compiling idna v0.2.0
[INFO] [stderr]    Compiling net2 v0.2.35
[INFO] [stderr]    Compiling iovec v0.1.4
[INFO] [stderr]    Compiling socket2 v0.3.15
[INFO] [stderr]    Compiling parking_lot_core v0.8.0
[INFO] [stderr]    Compiling want v0.3.0
[INFO] [stderr]    Compiling mio v0.6.22
[INFO] [stderr]    Compiling tracing v0.1.21
[INFO] [stderr]    Compiling parking_lot v0.11.0
[INFO] [stderr]    Compiling mime_guess v2.0.3
[INFO] [stderr]    Compiling url v2.1.1
[INFO] [stderr]    Compiling tokio v0.2.22
[INFO] [stderr]    Compiling flate2 v1.0.18
[INFO] [stderr]    Compiling async-compression v0.3.5
[INFO] [stderr]    Compiling serde_urlencoded v0.6.1
[INFO] [stderr]    Compiling tokio-util v0.3.1
[INFO] [stderr]    Compiling tokio-tls v0.3.1
[INFO] [stderr]    Compiling darling_core v0.10.2
[INFO] [stderr]    Compiling strum_macros v0.19.4
[INFO] [stderr]    Compiling darling_macro v0.10.2
[INFO] [stderr]    Compiling darling v0.10.2
[INFO] [stderr]    Compiling cached_proc_macro v0.4.0
[INFO] [stderr]    Compiling pin-project v0.4.27
[INFO] [stderr]    Compiling futures-util v0.3.6
[INFO] [stderr]    Compiling cached v0.19.0
[INFO] [stderr]    Compiling h2 v0.2.6
[INFO] [stderr]    Compiling hyper v0.13.8
[INFO] [stderr]    Compiling hyper-tls v0.4.3
[INFO] [stderr]    Compiling reqwest v0.10.8
[INFO] [stderr]    Compiling loader-rs v0.7.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]   --> src/lib.rs:43:1
[INFO] [stdout]    |
[INFO] [stdout] 43 | #![feature(specialization)]
[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/lib.rs:43:12
[INFO] [stdout]    |
[INFO] [stdout] 43 | #![feature(specialization)]
[INFO] [stdout]    |            ^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]   --> src/lib.rs:36:5
[INFO] [stdout]    |
[INFO] [stdout] 36 |     warnings,
[INFO] [stdout]    |     ^^^^^^^^
[INFO] [stdout]    = note: `#[warn(incomplete_features)]` implied by `#[warn(warnings)]`
[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 previous error; 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 `loader-rs`.
[INFO] [stderr] 
[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" "0a876fe826691282229df27e35e3a332ed6ace04eb9265d8df83ab67e381fb00", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0a876fe826691282229df27e35e3a332ed6ace04eb9265d8df83ab67e381fb00", kill_on_drop: false }`
[INFO] [stdout] 0a876fe826691282229df27e35e3a332ed6ace04eb9265d8df83ab67e381fb00
