[INFO] fetching crate backtracking_iterator 0.4.4...
[INFO] checking backtracking_iterator-0.4.4 against try#d990716b6a1fdde1300748828a9c9e79dfd0b898 for pr-74846
[INFO] extracting crate backtracking_iterator 0.4.4 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate backtracking_iterator 0.4.4 on toolchain d990716b6a1fdde1300748828a9c9e79dfd0b898
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking crates.io crate backtracking_iterator 0.4.4
[INFO] finished tweaking crates.io crate backtracking_iterator 0.4.4
[INFO] tweaked toml for crates.io crate backtracking_iterator 0.4.4 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c6ac66a725a409fd2b1a546d6bab84e9b2edf927e8eab8f7f11f1c4ea4aa1e1b
[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" "c6ac66a725a409fd2b1a546d6bab84e9b2edf927e8eab8f7f11f1c4ea4aa1e1b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c6ac66a725a409fd2b1a546d6bab84e9b2edf927e8eab8f7f11f1c4ea4aa1e1b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c6ac66a725a409fd2b1a546d6bab84e9b2edf927e8eab8f7f11f1c4ea4aa1e1b", kill_on_drop: false }`
[INFO] [stdout] c6ac66a725a409fd2b1a546d6bab84e9b2edf927e8eab8f7f11f1c4ea4aa1e1b
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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:a636fd89d022f18117e1dc8fb37a0a009933cdbbe082814857f0e2024962d47c" "/opt/rustwide/cargo-home/bin/cargo" "+d990716b6a1fdde1300748828a9c9e79dfd0b898" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 1dd26311c8e1bb8ac2c87cb5149e59d6190b037ebdd938b37628531b104c45e2
[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" "1dd26311c8e1bb8ac2c87cb5149e59d6190b037ebdd938b37628531b104c45e2", kill_on_drop: false }`
[INFO] [stderr]     Checking backtracking_iterator v0.4.4 (/opt/rustwide/workdir)
[INFO] [stdout] warning: the item `Backtracking` is imported redundantly
[INFO] [stdout]   --> src/copying.rs:38:17
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Backtracking` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 38 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Progressing` is imported redundantly
[INFO] [stdout]   --> src/copying.rs:38:31
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Progressing` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 38 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                               ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Backtracking` is imported redundantly
[INFO] [stdout]   --> src/referencing.rs:57:17
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Backtracking` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 57 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Progressing` is imported redundantly
[INFO] [stdout]   --> src/referencing.rs:57:31
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Progressing` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 57 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                               ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `BacktrackingState`
[INFO] [stdout]   --> src/concurrent.rs:22:13
[INFO] [stdout]    |
[INFO] [stdout] 22 | use super::{BacktrackingState, BacktrackingIterator};
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Backtracking`, `Progressing`
[INFO] [stdout]   --> src/concurrent.rs:72:17
[INFO] [stdout]    |
[INFO] [stdout] 72 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                 ^^^^^^^^^^^^  ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Backtracking`, `Progressing`
[INFO] [stdout]    --> src/concurrent.rs:140:17
[INFO] [stdout]     |
[INFO] [stdout] 140 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]     |                 ^^^^^^^^^^^^  ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Backtracking` is imported redundantly
[INFO] [stdout]   --> src/copying.rs:38:17
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Backtracking` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 38 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Progressing` is imported redundantly
[INFO] [stdout]   --> src/copying.rs:38:31
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Progressing` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 38 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                               ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Backtracking` is imported redundantly
[INFO] [stdout]   --> src/referencing.rs:57:17
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Backtracking` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 57 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                 ^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: the item `Progressing` is imported redundantly
[INFO] [stdout]   --> src/referencing.rs:57:31
[INFO] [stdout]    |
[INFO] [stdout] 23 | use super::BacktrackingState::*;
[INFO] [stdout]    |     --------------------------- the item `Progressing` is already imported here
[INFO] [stdout] ...
[INFO] [stdout] 57 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                               ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `BacktrackingState`
[INFO] [stdout]   --> src/concurrent.rs:22:13
[INFO] [stdout]    |
[INFO] [stdout] 22 | use super::{BacktrackingState, BacktrackingIterator};
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Backtracking`, `Progressing`
[INFO] [stdout]   --> src/concurrent.rs:72:17
[INFO] [stdout]    |
[INFO] [stdout] 72 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]    |                 ^^^^^^^^^^^^  ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused imports: `Backtracking`, `Progressing`
[INFO] [stdout]    --> src/concurrent.rs:140:17
[INFO] [stdout]     |
[INFO] [stdout] 140 |     use crate::{Backtracking, Progressing};
[INFO] [stdout]     |                 ^^^^^^^^^^^^  ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.62s
[INFO] running `Command { std: "docker" "inspect" "1dd26311c8e1bb8ac2c87cb5149e59d6190b037ebdd938b37628531b104c45e2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1dd26311c8e1bb8ac2c87cb5149e59d6190b037ebdd938b37628531b104c45e2", kill_on_drop: false }`
[INFO] [stdout] 1dd26311c8e1bb8ac2c87cb5149e59d6190b037ebdd938b37628531b104c45e2