[INFO] fetching crate mrkl 0.0.4...
[INFO] checking mrkl-0.0.4 against master#ceab6128fa48a616bfd3e3adf4bc80133b8ee223 for no-never-type-fallback
[INFO] extracting crate mrkl 0.0.4 into /workspace/builds/worker-6-tc1/source
[INFO] validating manifest of crates.io crate mrkl 0.0.4 on toolchain ceab6128fa48a616bfd3e3adf4bc80133b8ee223
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate mrkl 0.0.4
[INFO] finished tweaking crates.io crate mrkl 0.0.4
[INFO] tweaked toml for crates.io crate mrkl 0.0.4 written to /workspace/builds/worker-6-tc1/source/Cargo.toml
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 27 packages
[INFO] [stderr]       Adding block-buffer v0.7.3 (latest: v0.10.4)
[INFO] [stderr]       Adding block-padding v0.1.5 (latest: v0.3.3)
[INFO] [stderr]       Adding digest v0.8.1 (latest: v0.10.7)
[INFO] [stderr]       Adding generic-array v0.12.4 (latest: v1.0.0)
[INFO] [stderr]       Adding opaque-debug v0.2.3 (latest: v0.3.1)
[INFO] [stderr]       Adding sha2 v0.8.2 (latest: v0.10.8)
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded digest-hash v0.3.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0f38e80a263bb9ba5234389a411d519984e16b0147a5fdce58576a451f3ca6a2
[INFO] running `Command { std: "docker" "start" "-a" "0f38e80a263bb9ba5234389a411d519984e16b0147a5fdce58576a451f3ca6a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0f38e80a263bb9ba5234389a411d519984e16b0147a5fdce58576a451f3ca6a2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0f38e80a263bb9ba5234389a411d519984e16b0147a5fdce58576a451f3ca6a2", kill_on_drop: false }`
[INFO] [stdout] 0f38e80a263bb9ba5234389a411d519984e16b0147a5fdce58576a451f3ca6a2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+ceab6128fa48a616bfd3e3adf4bc80133b8ee223" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 611f24aa4906d5715ec59597d22925093a3113a44160193c1f2abe167a9efda3
[INFO] running `Command { std: "docker" "start" "-a" "611f24aa4906d5715ec59597d22925093a3113a44160193c1f2abe167a9efda3", kill_on_drop: false }`
[INFO] [stderr]     Checking byte-tools v0.3.1
[INFO] [stderr]     Checking either v1.10.0
[INFO] [stderr]     Checking fake-simd v0.1.2
[INFO] [stderr]     Checking opaque-debug v0.2.3
[INFO] [stderr]     Checking generic-array v0.12.4
[INFO] [stderr]     Checking rayon-core v1.12.1
[INFO] [stderr]     Checking block-padding v0.1.5
[INFO] [stderr]     Checking digest v0.8.1
[INFO] [stderr]     Checking block-buffer v0.7.3
[INFO] [stderr]     Checking digest-hash v0.3.0
[INFO] [stderr]     Checking sha2 v0.8.2
[INFO] [stderr]     Checking rayon v1.10.0
[INFO] [stderr]     Checking mrkl v0.0.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `IntoIterator` is imported redundantly
[INFO] [stdout]   --> src/tree/builder.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 | use std::iter::IntoIterator;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `IntoIterator` is already defined here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `DoubleEndedIterator` is imported redundantly
[INFO] [stdout]   --> src/tree/mod.rs:38:17
[INFO] [stdout]    |
[INFO] [stdout] 38 | use std::iter::{DoubleEndedIterator, ExactSizeIterator, Iterator};
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `DoubleEndedIterator` is already defined here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `ExactSizeIterator` is imported redundantly
[INFO] [stdout]   --> src/tree/mod.rs:38:38
[INFO] [stdout]    |
[INFO] [stdout] 38 | use std::iter::{DoubleEndedIterator, ExactSizeIterator, Iterator};
[INFO] [stdout]    |                                      ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `ExactSizeIterator` is already defined here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Iterator` is imported redundantly
[INFO] [stdout]   --> src/tree/mod.rs:38:57
[INFO] [stdout]    |
[INFO] [stdout] 38 | use std::iter::{DoubleEndedIterator, ExactSizeIterator, Iterator};
[INFO] [stdout]    |                                                         ^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `Iterator` is already defined here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `IntoIterator` is imported redundantly
[INFO] [stdout]   --> src/tree/builder.rs:17:5
[INFO] [stdout]    |
[INFO] [stdout] 17 | use std::iter::IntoIterator;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `IntoIterator` is already defined here
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `DoubleEndedIterator` is imported redundantly
[INFO] [stdout]   --> src/tree/mod.rs:38:17
[INFO] [stdout]    |
[INFO] [stdout] 38 | use std::iter::{DoubleEndedIterator, ExactSizeIterator, Iterator};
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `DoubleEndedIterator` is already defined here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `ExactSizeIterator` is imported redundantly
[INFO] [stdout]   --> src/tree/mod.rs:38:38
[INFO] [stdout]    |
[INFO] [stdout] 38 | use std::iter::{DoubleEndedIterator, ExactSizeIterator, Iterator};
[INFO] [stdout]    |                                      ^^^^^^^^^^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `ExactSizeIterator` is already defined here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Iterator` is imported redundantly
[INFO] [stdout]   --> src/tree/mod.rs:38:57
[INFO] [stdout]    |
[INFO] [stdout] 38 | use std::iter::{DoubleEndedIterator, ExactSizeIterator, Iterator};
[INFO] [stdout]    |                                                         ^^^^^^^^
[INFO] [stdout]   --> /rustc/ceab6128fa48a616bfd3e3adf4bc80133b8ee223/library/std/src/prelude/mod.rs:124:13
[INFO] [stdout]    |
[INFO] [stdout]    = note: the item `Iterator` is already defined here
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.56s
[INFO] running `Command { std: "docker" "inspect" "611f24aa4906d5715ec59597d22925093a3113a44160193c1f2abe167a9efda3", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "611f24aa4906d5715ec59597d22925093a3113a44160193c1f2abe167a9efda3", kill_on_drop: false }`
[INFO] [stdout] 611f24aa4906d5715ec59597d22925093a3113a44160193c1f2abe167a9efda3