[INFO] fetching crate polynomial-roots 1.0.0...
[INFO] checking polynomial-roots-1.0.0 against master#040e2f8b9ff2d76fbe2146d6003e297ed4532088 for pr-143619
[INFO] extracting crate polynomial-roots 1.0.0 into /workspace/builds/worker-4-tc1/source
[INFO] started tweaking crates.io crate polynomial-roots 1.0.0
[INFO] finished tweaking crates.io crate polynomial-roots 1.0.0
[INFO] tweaked toml for crates.io crate polynomial-roots 1.0.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate polynomial-roots 1.0.0 on toolchain 040e2f8b9ff2d76fbe2146d6003e297ed4532088
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+040e2f8b9ff2d76fbe2146d6003e297ed4532088" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate polynomial-roots 1.0.0 already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+040e2f8b9ff2d76fbe2146d6003e297ed4532088" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e8955075918b6d00525c617f7c34ee2595c70db70b3cf844dc875e4d3604499b" "/opt/rustwide/cargo-home/bin/cargo" "+040e2f8b9ff2d76fbe2146d6003e297ed4532088" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] b67838fd3359b73d9a3d9e67e4e3bd6bc0fee08bba2626f4c926b87127333a0c
[INFO] running `Command { std: "docker" "start" "-a" "b67838fd3359b73d9a3d9e67e4e3bd6bc0fee08bba2626f4c926b87127333a0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "b67838fd3359b73d9a3d9e67e4e3bd6bc0fee08bba2626f4c926b87127333a0c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b67838fd3359b73d9a3d9e67e4e3bd6bc0fee08bba2626f4c926b87127333a0c", kill_on_drop: false }`
[INFO] [stdout] b67838fd3359b73d9a3d9e67e4e3bd6bc0fee08bba2626f4c926b87127333a0c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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" "RUSTDOCFLAGS=--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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:e8955075918b6d00525c617f7c34ee2595c70db70b3cf844dc875e4d3604499b" "/opt/rustwide/cargo-home/bin/cargo" "+040e2f8b9ff2d76fbe2146d6003e297ed4532088" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1f12e7cb71d41d34d83b10b87097b118e1f5a299f06909d727cff56eb6828a68
[INFO] running `Command { std: "docker" "start" "-a" "1f12e7cb71d41d34d83b10b87097b118e1f5a299f06909d727cff56eb6828a68", kill_on_drop: false }`
[INFO] [stderr]     Checking polynomial-roots v1.0.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]   --> src/polynomials.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     &self,
[INFO] [stdout]    |     ^^^^^ this lifetime flows to the output
[INFO] [stdout] 49 |   ) -> std::collections::linked_list::Iter<f32> {
[INFO] [stdout]    |        ---------------------------------------- the lifetime gets resolved as `'_`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]    |
[INFO] [stdout] 49 |   ) -> std::collections::linked_list::Iter<'_, f32> {
[INFO] [stdout]    |                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: lifetime flowing from input to output with different syntax can be confusing
[INFO] [stdout]   --> src/polynomials.rs:48:5
[INFO] [stdout]    |
[INFO] [stdout] 48 |     &self,
[INFO] [stdout]    |     ^^^^^ this lifetime flows to the output
[INFO] [stdout] 49 |   ) -> std::collections::linked_list::Iter<f32> {
[INFO] [stdout]    |        ---------------------------------------- the lifetime gets resolved as `'_`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: one option is to remove the lifetime for references and use the anonymous lifetime for paths
[INFO] [stdout]    |
[INFO] [stdout] 49 |   ) -> std::collections::linked_list::Iter<'_, f32> {
[INFO] [stdout]    |                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.12s
[INFO] running `Command { std: "docker" "inspect" "1f12e7cb71d41d34d83b10b87097b118e1f5a299f06909d727cff56eb6828a68", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1f12e7cb71d41d34d83b10b87097b118e1f5a299f06909d727cff56eb6828a68", kill_on_drop: false }`
[INFO] [stdout] 1f12e7cb71d41d34d83b10b87097b118e1f5a299f06909d727cff56eb6828a68