[INFO] cloning repository https://github.com/rust-real-time-os/os_lab
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/rust-real-time-os/os_lab" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frust-real-time-os%2Fos_lab", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frust-real-time-os%2Fos_lab'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4fe53abda22acf546525936027055e64cb5379a8
[INFO] checking rust-real-time-os/os_lab against 79c0559184f27f4433a6fbc260b950d06d4a4889 for pr-162233-crater-rollup
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Frust-real-time-os%2Fos_lab" "/workspace/builds/worker-1-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/rust-real-time-os/os_lab
[INFO] finished tweaking git repo https://github.com/rust-real-time-os/os_lab
[INFO] tweaked toml for git repo https://github.com/rust-real-time-os/os_lab written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/rust-real-time-os/os_lab on toolchain 79c0559184f27f4433a6fbc260b950d06d4a4889
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+79c0559184f27f4433a6fbc260b950d06d4a4889" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/rust-real-time-os/os_lab 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" "+79c0559184f27f4433a6fbc260b950d06d4a4889" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded getrandom v0.2.8
[INFO] [stderr]   Downloaded ppv-lite86 v0.2.17
[INFO] [stderr]   Downloaded libc v0.2.139
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc2/target:/opt/rustwide/target:rw,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" "-m" "1610612736" "--network" "none" "ghcr.io/rust-lang/crates-build-env/linux@sha256:8683fc1fc2eb5c9ac98e0d076ab094b2ffac7f99da555d2b6a2e27f346de2ec7" "sleep" "infinity", kill_on_drop: false }`
[INFO] [stdout] e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7
[INFO] running `Command { std: "docker" "start" "e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-w" "/opt/rustwide/workdir" "--user" "0:0" "e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7" "/opt/rustwide/cargo-home/bin/cargo" "+79c0559184f27f4433a6fbc260b950d06d4a4889" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "exec" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-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" "-w" "/opt/rustwide/workdir" "--user" "0:0" "e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7" "/opt/rustwide/cargo-home/bin/cargo" "+79c0559184f27f4433a6fbc260b950d06d4a4889" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.139
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking ppv-lite86 v0.2.17
[INFO] [stderr]     Checking getrandom v0.2.8
[INFO] [stderr]     Checking rand_core v0.6.4
[INFO] [stderr]     Checking rand_chacha v0.3.1
[INFO] [stderr]     Checking rand v0.8.5
[INFO] [stderr]     Checking linked_list v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `predicate`
[INFO] [stdout]    --> src/double_linked_list.rs:268:34
[INFO] [stdout]     |
[INFO] [stdout] 268 |     pub fn find_mut<P>(&mut self,predicate:P)->Option<&mut T> where P:Fn(&T) -> bool{
[INFO] [stdout]     |                                  ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_predicate`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Node` is never constructed
[INFO] [stdout]   --> src/double_linked_list.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | struct Node<T> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/double_linked_list.rs:175:17
[INFO] [stdout]     |
[INFO] [stdout] 175 |     pub fn iter(&self) -> Iter<T> {
[INFO] [stdout]     |                 ^^^^^     ^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 175 |     pub fn iter(&self) -> Iter<'_, T> {
[INFO] [stdout]     |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/double_linked_list.rs:184:21
[INFO] [stdout]     |
[INFO] [stdout] 184 |     pub fn iter_mut(&mut self) -> IterMut<T> {
[INFO] [stdout]     |                     ^^^^^^^^^     ^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 184 |     pub fn iter_mut(&mut self) -> IterMut<'_, T> {
[INFO] [stdout]     |                                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `predicate`
[INFO] [stdout]    --> src/double_linked_list.rs:268:34
[INFO] [stdout]     |
[INFO] [stdout] 268 |     pub fn find_mut<P>(&mut self,predicate:P)->Option<&mut T> where P:Fn(&T) -> bool{
[INFO] [stdout]     |                                  ^^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_predicate`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Node` is never constructed
[INFO] [stdout]   --> src/double_linked_list.rs:13:8
[INFO] [stdout]    |
[INFO] [stdout] 13 | struct Node<T> {
[INFO] [stdout]    |        ^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/double_linked_list.rs:175:17
[INFO] [stdout]     |
[INFO] [stdout] 175 |     pub fn iter(&self) -> Iter<T> {
[INFO] [stdout]     |                 ^^^^^     ^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                 |
[INFO] [stdout]     |                 the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout]     = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 175 |     pub fn iter(&self) -> Iter<'_, T> {
[INFO] [stdout]     |                                +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/double_linked_list.rs:184:21
[INFO] [stdout]     |
[INFO] [stdout] 184 |     pub fn iter_mut(&mut self) -> IterMut<T> {
[INFO] [stdout]     |                     ^^^^^^^^^     ^^^^^^^^^^ the same lifetime is hidden here
[INFO] [stdout]     |                     |
[INFO] [stdout]     |                     the lifetime is elided here
[INFO] [stdout]     |
[INFO] [stdout]     = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
[INFO] [stdout] help: use `'_` for type paths
[INFO] [stdout]     |
[INFO] [stdout] 184 |     pub fn iter_mut(&mut self) -> IterMut<'_, T> {
[INFO] [stdout]     |                                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.86s
[INFO] running `Command { std: "docker" "inspect" "e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7", kill_on_drop: false }`
[INFO] [stdout] e790bd7e4d5c98d2c12896dcd3d293ebd1bc6f9ddb72bd53f7a02fb3b218eaa7
