[INFO] fetching crate conjecture 0.4.0...
[INFO] checking conjecture-0.4.0 against beta for pr-78714
[INFO] extracting crate conjecture 0.4.0 into /workspace/builds/worker-9/source
[INFO] validating manifest of crates.io crate conjecture 0.4.0 on toolchain beta
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate conjecture 0.4.0
[INFO] finished tweaking crates.io crate conjecture 0.4.0
[INFO] tweaked toml for crates.io crate conjecture 0.4.0 written to /workspace/builds/worker-9/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+beta" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a25cfcb00a44894c8f6062dced0b5fa94631ed2ca3ed71a866a6e304de7893c6
[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" "a25cfcb00a44894c8f6062dced0b5fa94631ed2ca3ed71a866a6e304de7893c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a25cfcb00a44894c8f6062dced0b5fa94631ed2ca3ed71a866a6e304de7893c6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a25cfcb00a44894c8f6062dced0b5fa94631ed2ca3ed71a866a6e304de7893c6", kill_on_drop: false }`
[INFO] [stdout] a25cfcb00a44894c8f6062dced0b5fa94631ed2ca3ed71a866a6e304de7893c6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-9/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=forbid" "-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@sha256:6eabd152ff4036248d66efda456a36cb33d24b7291b33f25f75140726c88da35" "/opt/rustwide/cargo-home/bin/cargo" "+beta" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] b1c94bee420395a7c6f378ea39a9566b888e101b4668bbbd835db3dd9d89163b
[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" "b1c94bee420395a7c6f378ea39a9566b888e101b4668bbbd835db3dd9d89163b", kill_on_drop: false }`
[INFO] [stderr]     Checking tempdir v0.3.7
[INFO] [stderr]     Checking conjecture v0.4.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/database.rs:17:30
[INFO] [stdout]    |
[INFO] [stdout] 17 | pub type BoxedDatabase = Box<Database>;
[INFO] [stdout]    |                              ^^^^^^^^ help: use `dyn`: `dyn Database`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait objects without an explicit `dyn` are deprecated
[INFO] [stdout]   --> src/database.rs:17:30
[INFO] [stdout]    |
[INFO] [stdout] 17 | pub type BoxedDatabase = Box<Database>;
[INFO] [stdout]    |                              ^^^^^^^^ help: use `dyn`: `dyn Database`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(bare_trait_objects)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/engine.rs:157:21
[INFO] [stdout]     |
[INFO] [stdout] 157 |                 let mut minimized_examples = &mut self.minimized_examples;
[INFO] [stdout]     |                     ----^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/engine.rs:158:21
[INFO] [stdout]     |
[INFO] [stdout] 158 |                 let mut database = &mut self.database;
[INFO] [stdout]     |                     ----^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/engine.rs:157:21
[INFO] [stdout]     |
[INFO] [stdout] 157 |                 let mut minimized_examples = &mut self.minimized_examples;
[INFO] [stdout]     |                     ----^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/engine.rs:158:21
[INFO] [stdout]     |
[INFO] [stdout] 158 |                 let mut database = &mut self.database;
[INFO] [stdout]     |                     ----^^^^^^^^
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 1.10s
[INFO] running `Command { std: "docker" "inspect" "b1c94bee420395a7c6f378ea39a9566b888e101b4668bbbd835db3dd9d89163b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b1c94bee420395a7c6f378ea39a9566b888e101b4668bbbd835db3dd9d89163b", kill_on_drop: false }`
[INFO] [stdout] b1c94bee420395a7c6f378ea39a9566b888e101b4668bbbd835db3dd9d89163b