[INFO] fetching crate cow_vec_item 0.5.0...
[INFO] testing cow_vec_item-0.5.0 against 1.47.0 for beta-1.48-1
[INFO] extracting crate cow_vec_item 0.5.0 into /workspace/builds/worker-2/source
[INFO] validating manifest of crates.io crate cow_vec_item 0.5.0 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 cow_vec_item 0.5.0
[INFO] finished tweaking crates.io crate cow_vec_item 0.5.0
[INFO] tweaked toml for crates.io crate cow_vec_item 0.5.0 written to /workspace/builds/worker-2/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-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] 0bd7855a8cb7598fc66d3dc0d34f595eca9605ed4bc6f8c3865343e1d7edd61a
[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" "0bd7855a8cb7598fc66d3dc0d34f595eca9605ed4bc6f8c3865343e1d7edd61a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0bd7855a8cb7598fc66d3dc0d34f595eca9605ed4bc6f8c3865343e1d7edd61a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0bd7855a8cb7598fc66d3dc0d34f595eca9605ed4bc6f8c3865343e1d7edd61a", kill_on_drop: false }`
[INFO] [stdout] 0bd7855a8cb7598fc66d3dc0d34f595eca9605ed4bc6f8c3865343e1d7edd61a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 5f0176be6343ee214033dc29a9dcf149c67d901c611737cf2106fb3515199a0c
[INFO] running `Command { std: "docker" "start" "-a" "5f0176be6343ee214033dc29a9dcf149c67d901c611737cf2106fb3515199a0c", kill_on_drop: false }`
[INFO] [stderr]    Compiling cow_vec_item v0.5.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:232:19
[INFO] [stdout]     |
[INFO] [stdout] 232 |         *unsafe { (&mut *self.bad_wrapper_use_detector) } = WrapperState::Dead;
[INFO] [stdout]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:2:9
[INFO] [stdout]     |
[INFO] [stdout] 2   | #![deny(warnings)]
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     = note: `#[warn(unused_parens)]` implied by `#[warn(warnings)]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:546:22
[INFO] [stdout]     |
[INFO] [stdout] 546 |         if *unsafe { (&*self.bad_wrapper_use_detector) } != WrapperState::Dead {
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:581:22
[INFO] [stdout]     |
[INFO] [stdout] 581 |         if *unsafe { (&*self.bad_wrapper_use_detector) } != WrapperState::Dead {
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.36s
[INFO] running `Command { std: "docker" "inspect" "5f0176be6343ee214033dc29a9dcf149c67d901c611737cf2106fb3515199a0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5f0176be6343ee214033dc29a9dcf149c67d901c611737cf2106fb3515199a0c", kill_on_drop: false }`
[INFO] [stdout] 5f0176be6343ee214033dc29a9dcf149c67d901c611737cf2106fb3515199a0c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-2/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" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] dfac521564a9e7ae86e597eccf5cb054f5103f0a30040975bac8c5b43851215d
[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" "dfac521564a9e7ae86e597eccf5cb054f5103f0a30040975bac8c5b43851215d", kill_on_drop: false }`
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:232:19
[INFO] [stdout]     |
[INFO] [stdout] 232 |         *unsafe { (&mut *self.bad_wrapper_use_detector) } = WrapperState::Dead;
[INFO] [stdout]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:2:9
[INFO] [stdout]     |
[INFO] [stdout] 2   | #![deny(warnings)]
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     = note: `#[warn(unused_parens)]` implied by `#[warn(warnings)]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling cow_vec_item v0.5.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:546:22
[INFO] [stdout]     |
[INFO] [stdout] 546 |         if *unsafe { (&*self.bad_wrapper_use_detector) } != WrapperState::Dead {
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:581:22
[INFO] [stdout]     |
[INFO] [stdout] 581 |         if *unsafe { (&*self.bad_wrapper_use_detector) } != WrapperState::Dead {
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> src/lib.rs:3:19
[INFO] [stdout]   |
[INFO] [stdout] 3 | #![cfg_attr(test, feature(test))]
[INFO] [stdout]   |                   ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:232:19
[INFO] [stdout]     |
[INFO] [stdout] 232 |         *unsafe { (&mut *self.bad_wrapper_use_detector) } = WrapperState::Dead;
[INFO] [stdout]     |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout]     |
[INFO] [stdout] note: the lint level is defined here
[INFO] [stdout]    --> src/lib.rs:2:9
[INFO] [stdout]     |
[INFO] [stdout] 2   | #![deny(warnings)]
[INFO] [stdout]     |         ^^^^^^^^
[INFO] [stdout]     = note: `#[warn(unused_parens)]` implied by `#[warn(warnings)]`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:546:22
[INFO] [stdout]     |
[INFO] [stdout] 546 |         if *unsafe { (&*self.bad_wrapper_use_detector) } != WrapperState::Dead {
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unnecessary parentheses around block return value
[INFO] [stdout]    --> src/lib.rs:581:22
[INFO] [stdout]     |
[INFO] [stdout] 581 |         if *unsafe { (&*self.bad_wrapper_use_detector) } != WrapperState::Dead {
[INFO] [stdout]     |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: remove these parentheses
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error; 3 warnings 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 `cow_vec_item`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `Command { std: "docker" "inspect" "dfac521564a9e7ae86e597eccf5cb054f5103f0a30040975bac8c5b43851215d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dfac521564a9e7ae86e597eccf5cb054f5103f0a30040975bac8c5b43851215d", kill_on_drop: false }`
[INFO] [stdout] dfac521564a9e7ae86e597eccf5cb054f5103f0a30040975bac8c5b43851215d
