[INFO] fetching crate railsgun 3.0.1...
[INFO] checking railsgun-3.0.1 against try#0611f7de057c584b8771102fde7aed6c70c71d3b for pr-146440
[INFO] extracting crate railsgun 3.0.1 into /workspace/builds/worker-6-tc2/source
[INFO] started tweaking crates.io crate railsgun 3.0.1
[INFO] finished tweaking crates.io crate railsgun 3.0.1
[INFO] tweaked toml for crates.io crate railsgun 3.0.1 written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] validating manifest of crates.io crate railsgun 3.0.1 on toolchain 0611f7de057c584b8771102fde7aed6c70c71d3b
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "generate-lockfile" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]      Locking 7 packages to latest compatible versions
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 6f1e785b2aae3ae13c5e6036fa857f63449649ea563f1f19e50c01c351219eed
[INFO] running `Command { std: "docker" "start" "-a" "6f1e785b2aae3ae13c5e6036fa857f63449649ea563f1f19e50c01c351219eed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "6f1e785b2aae3ae13c5e6036fa857f63449649ea563f1f19e50c01c351219eed", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "6f1e785b2aae3ae13c5e6036fa857f63449649ea563f1f19e50c01c351219eed", kill_on_drop: false }`
[INFO] [stdout] 6f1e785b2aae3ae13c5e6036fa857f63449649ea563f1f19e50c01c351219eed
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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:d429b63d4308055ea97f60fb1d3dfca48854a00942f1bd2ad806beaf015945ec" "/opt/rustwide/cargo-home/bin/cargo" "+0611f7de057c584b8771102fde7aed6c70c71d3b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 7080bd64dc363f7653af462693d74f1389e3ebd12257c69d9642726a644c2dcc
[INFO] running `Command { std: "docker" "start" "-a" "7080bd64dc363f7653af462693d74f1389e3ebd12257c69d9642726a644c2dcc", kill_on_drop: false }`
[INFO] [stderr]     Checking tokio v1.52.3
[INFO] [stderr]     Checking railsgun v3.0.1 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused `#[macro_use]` import
[INFO] [stdout]    --> src/lib.rs:107:1
[INFO] [stdout]     |
[INFO] [stdout] 107 | #[macro_use]
[INFO] [stdout]     | ^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/option_extended/mod.rs:273:5
[INFO] [stdout]     |
[INFO] [stdout] 273 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, foreign functions, functions, inherent methods, provided trait methods, required trait methods, and traits
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/option_extended/mod.rs:355:5
[INFO] [stdout]     |
[INFO] [stdout] 355 |     #[must_use = "if you intended to set a value, consider assignment instead"]
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, foreign functions, functions, inherent methods, provided trait methods, required trait methods, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/option_extended/mod.rs:513:5
[INFO] [stdout]     |
[INFO] [stdout] 513 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, foreign functions, functions, inherent methods, provided trait methods, required trait methods, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/option_extended/mod.rs:273:5
[INFO] [stdout]     |
[INFO] [stdout] 273 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, foreign functions, functions, inherent methods, provided trait methods, required trait methods, and traits
[INFO] [stdout]     = note: `#[warn(unused_attributes)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/option_extended/mod.rs:355:5
[INFO] [stdout]     |
[INFO] [stdout] 355 |     #[must_use = "if you intended to set a value, consider assignment instead"]
[INFO] [stdout]     |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, foreign functions, functions, inherent methods, provided trait methods, required trait methods, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: `#[must_use]` attribute cannot be used on trait methods in impl blocks
[INFO] [stdout]    --> src/option_extended/mod.rs:513:5
[INFO] [stdout]     |
[INFO] [stdout] 513 |     #[must_use]
[INFO] [stdout]     |     ^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
[INFO] [stdout]     = help: `#[must_use]` can be applied to data types, foreign functions, functions, inherent methods, provided trait methods, required trait methods, and traits
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: struct `IterMut` is never constructed
[INFO] [stdout]    --> src/option_extended/mod.rs:671:12
[INFO] [stdout]     |
[INFO] [stdout] 671 | pub struct IterMut<'a, A: 'a> {
[INFO] [stdout]     |            ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `pub` struct has private fields, no public constructor, and is not otherwise reachable through the external API, so consider providing a public constructor or removing it
[INFO] [stdout]     = note: `#[deny(unused_unconstructable_pub_struct)]` (part of `#[deny(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `railsgun` (lib) due to 1 previous error; 4 warnings emitted
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] error: struct `IterMut` is never constructed
[INFO] [stdout]    --> src/option_extended/mod.rs:671:12
[INFO] [stdout]     |
[INFO] [stdout] 671 | pub struct IterMut<'a, A: 'a> {
[INFO] [stdout]     |            ^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: this `pub` struct has private fields, no public constructor, and is not otherwise reachable through the external API, so consider providing a public constructor or removing it
[INFO] [stdout]     = note: `#[deny(unused_unconstructable_pub_struct)]` (part of `#[deny(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Empty` is never constructed
[INFO] [stdout]   --> src/iterators/map_iterator.rs:32:9
[INFO] [stdout]    |
[INFO] [stdout] 31 |     enum TestError {
[INFO] [stdout]    |          --------- variant in this enum
[INFO] [stdout] 32 |         Empty,
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `TestError` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant `Custom` is never constructed
[INFO] [stdout]    --> src/iterators/mod.rs:105:9
[INFO] [stdout]     |
[INFO] [stdout] 103 |     enum TestError {
[INFO] [stdout]     |          --------- variant in this enum
[INFO] [stdout] 104 |         Empty,
[INFO] [stdout] 105 |         Custom,
[INFO] [stdout]     |         ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `TestError` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `railsgun` (lib test) due to 1 previous error; 5 warnings emitted
[INFO] running `Command { std: "docker" "inspect" "7080bd64dc363f7653af462693d74f1389e3ebd12257c69d9642726a644c2dcc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7080bd64dc363f7653af462693d74f1389e3ebd12257c69d9642726a644c2dcc", kill_on_drop: false }`
[INFO] [stdout] 7080bd64dc363f7653af462693d74f1389e3ebd12257c69d9642726a644c2dcc
