[INFO] cloning repository https://github.com/bookinstock/rust_example
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/bookinstock/rust_example" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbookinstock%2Frust_example", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbookinstock%2Frust_example'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] c83d144f2d500cd60a59da5019b4bc5ca7d2d36f
[INFO] checking bookinstock/rust_example against master#90442458ac46b1d5eed752c316da25450f67285b for pr-81477
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbookinstock%2Frust_example" "/workspace/builds/worker-7/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/bookinstock/rust_example on toolchain 90442458ac46b1d5eed752c316da25450f67285b
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/bookinstock/rust_example
[INFO] finished tweaking git repo https://github.com/bookinstock/rust_example
[INFO] tweaked toml for git repo https://github.com/bookinstock/rust_example written to /workspace/builds/worker-7/source/Cargo.toml
[INFO] crate git repo https://github.com/bookinstock/rust_example already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 7ff3e81be7dba3782afdf7a7da41bfe691b95931a8fede11ceaedda82d9949d2
[INFO] running `Command { std: "docker" "start" "-a" "7ff3e81be7dba3782afdf7a7da41bfe691b95931a8fede11ceaedda82d9949d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7ff3e81be7dba3782afdf7a7da41bfe691b95931a8fede11ceaedda82d9949d2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7ff3e81be7dba3782afdf7a7da41bfe691b95931a8fede11ceaedda82d9949d2", kill_on_drop: false }`
[INFO] [stdout] 7ff3e81be7dba3782afdf7a7da41bfe691b95931a8fede11ceaedda82d9949d2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7/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" "ghcr.io/rust-lang/crates-build-env/linux@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+90442458ac46b1d5eed752c316da25450f67285b" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] b08980b3d1a8643ddeb7753ab412747d11596f2ed322f7f61cd45e6462579a9d
[INFO] running `Command { std: "docker" "start" "-a" "b08980b3d1a8643ddeb7753ab412747d11596f2ed322f7f61cd45e6462579a9d", kill_on_drop: false }`
[INFO] [stderr]     Checking rust_example v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0601]: `main` function not found in crate `test`
[INFO] [stdout]   --> src/bin/test.rs:13:4
[INFO] [stdout]    |
[INFO] [stdout] 13 | */
[INFO] [stdout]    |    ^ consider adding a `main` function to `src/bin/test.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `rust_example`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stdout] warning: function is never used: `test_literal`
[INFO] [stdout]    --> src/bin/pattern_matching.rs:113:4
[INFO] [stdout]     |
[INFO] [stdout] 113 | fn test_literal() {}
[INFO] [stdout]     |    ^^^^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_array`
[INFO] [stdout]    --> src/bin/pattern_matching.rs:115:4
[INFO] [stdout]     |
[INFO] [stdout] 115 | fn test_array() {}
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_enum`
[INFO] [stdout]    --> src/bin/pattern_matching.rs:117:4
[INFO] [stdout]     |
[INFO] [stdout] 117 | fn test_enum() {}
[INFO] [stdout]     |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_stuct`
[INFO] [stdout]    --> src/bin/pattern_matching.rs:119:4
[INFO] [stdout]     |
[INFO] [stdout] 119 | fn test_stuct() {}
[INFO] [stdout]     |    ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_variable`
[INFO] [stdout]    --> src/bin/pattern_matching.rs:137:4
[INFO] [stdout]     |
[INFO] [stdout] 137 | fn test_variable() {}
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_wildcard`
[INFO] [stdout]    --> src/bin/pattern_matching.rs:139:4
[INFO] [stdout]     |
[INFO] [stdout] 139 | fn test_wildcard() {}
[INFO] [stdout]     |    ^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_placeholder`
[INFO] [stdout]    --> src/bin/pattern_matching.rs:141:4
[INFO] [stdout]     |
[INFO] [stdout] 141 | fn test_placeholder() {}
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `std`
[INFO] [stdout]   --> src/bin/std.rs:64:4
[INFO] [stdout]    |
[INFO] [stdout] 64 | */
[INFO] [stdout]    |    ^ consider adding a `main` function to `src/bin/std.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 7 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stdout] error[E0601]: `main` function not found in crate `trait`
[INFO] [stdout]   --> src/bin/trait.rs:15:4
[INFO] [stdout]    |
[INFO] [stdout] 15 | */
[INFO] [stdout]    |    ^ consider adding a `main` function to `src/bin/trait.rs`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0601`.
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `vec2`
[INFO] [stdout]    --> src/bin/function.rs:391:9
[INFO] [stdout]     |
[INFO] [stdout] 391 |     let vec2 = vec![4, 5, 6];
[INFO] [stdout]     |         ^^^^ help: if this is intentional, prefix it with an underscore: `_vec2`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: this method call resolves to `<&[T; N] as IntoIterator>::into_iter` (due to backwards compatibility), but will resolve to <[T; N] as IntoIterator>::into_iter in Rust 2021.
[INFO] [stdout]    --> src/bin/function.rs:431:16
[INFO] [stdout]     |
[INFO] [stdout] 431 |         array2.into_iter().find(|&&x| x == 2)
[INFO] [stdout]     |                ^^^^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(array_into_iter)]` on by default
[INFO] [stdout]     = warning: this changes meaning in Rust 2021
[INFO] [stdout]     = note: for more information, see issue #66145 <https://github.com/rust-lang/rust/issues/66145>
[INFO] [stdout] help: use `.iter()` instead of `.into_iter()` to avoid ambiguity
[INFO] [stdout]     |
[INFO] [stdout] 431 |         array2.iter().find(|&&x| x == 2)
[INFO] [stdout]     |                ^^^^
[INFO] [stdout] help: or use `IntoIterator::into_iter(..)` instead of `.into_iter()` to explicitly iterate by value
[INFO] [stdout]     |
[INFO] [stdout] 431 |         IntoIterator::into_iter(array2).find(|&&x| x == 2)
[INFO] [stdout]     |         ^^^^^^^^^^^^^^^^^^^^^^^^      ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `x`
[INFO] [stdout]   --> src/bin/scope.rs:88:9
[INFO] [stdout]    |
[INFO] [stdout] 88 |     let x = ToDrop;
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_x`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `ref_x`
[INFO] [stdout]    --> src/bin/scope.rs:401:13
[INFO] [stdout]     |
[INFO] [stdout] 401 |         let ref_x = &x;
[INFO] [stdout]     |             ^^^^^ help: if this is intentional, prefix it with an underscore: `_ref_x`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `noisy_unused_variable`
[INFO] [stdout]   --> src/bin/var_binding.rs:26:9
[INFO] [stdout]    |
[INFO] [stdout] 26 |     let noisy_unused_variable = 2u32;
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_noisy_unused_variable`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: path statement with no effect
[INFO] [stdout]   --> src/bin/expression.rs:18:5
[INFO] [stdout]    |
[INFO] [stdout] 18 |     x;
[INFO] [stdout]    |     ^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(path_statements)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]    --> src/bin/scope.rs:405:13
[INFO] [stdout]     |
[INFO] [stdout] 405 |         let mut ref_x = &mut x;
[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: unused arithmetic operation that must be used
[INFO] [stdout]   --> src/bin/expression.rs:19:5
[INFO] [stdout]    |
[INFO] [stdout] 19 |     x + 1;
[INFO] [stdout]    |     ^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused arithmetic operation that must be used
[INFO] [stdout]   --> src/bin/expression.rs:36:9
[INFO] [stdout]    |
[INFO] [stdout] 36 |         2 * x;
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `ps_ref`
[INFO] [stdout]    --> src/bin/scope.rs:444:4
[INFO] [stdout]     |
[INFO] [stdout] 444 | fn ps_ref() {
[INFO] [stdout]     |    ^^^^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `ttt`
[INFO] [stdout]    --> src/bin/hello.rs:107:4
[INFO] [stdout]     |
[INFO] [stdout] 107 | fn ttt() {
[INFO] [stdout]     |    ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `f`
[INFO] [stdout]    --> src/bin/hello.rs:120:4
[INFO] [stdout]     |
[INFO] [stdout] 120 | fn f() {
[INFO] [stdout]     |    ^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test`
[INFO] [stdout]    --> src/bin/hello.rs:124:4
[INFO] [stdout]     |
[INFO] [stdout] 124 | fn test() {
[INFO] [stdout]     |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `try_debug_trait`
[INFO] [stdout]    --> src/bin/hello.rs:159:4
[INFO] [stdout]     |
[INFO] [stdout] 159 | fn try_debug_trait() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 4 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct is never constructed: `Nil`
[INFO] [stdout]   --> src/bin/custom_type.rs:30:8
[INFO] [stdout]    |
[INFO] [stdout] 30 | struct Nil;
[INFO] [stdout]    |        ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "b08980b3d1a8643ddeb7753ab412747d11596f2ed322f7f61cd45e6462579a9d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "b08980b3d1a8643ddeb7753ab412747d11596f2ed322f7f61cd45e6462579a9d", kill_on_drop: false }`
[INFO] [stdout] b08980b3d1a8643ddeb7753ab412747d11596f2ed322f7f61cd45e6462579a9d