[INFO] cloning repository https://github.com/johancc/too-many-linked-lists
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/johancc/too-many-linked-lists" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjohancc%2Ftoo-many-linked-lists", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjohancc%2Ftoo-many-linked-lists'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 4fe6cf27a61135e0280a2f14a34be242578f52b7
[INFO] checking johancc/too-many-linked-lists against 49a6044d37d694890450f52ceaceb66277a36b1e for pr-161154
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjohancc%2Ftoo-many-linked-lists" "/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/johancc/too-many-linked-lists
[INFO] finished tweaking git repo https://github.com/johancc/too-many-linked-lists
[INFO] tweaked toml for git repo https://github.com/johancc/too-many-linked-lists written to /workspace/builds/worker-1-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/johancc/too-many-linked-lists on toolchain 49a6044d37d694890450f52ceaceb66277a36b1e
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+49a6044d37d694890450f52ceaceb66277a36b1e" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/johancc/too-many-linked-lists 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" "+49a6044d37d694890450f52ceaceb66277a36b1e" "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] 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] 1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee
[INFO] running `Command { std: "docker" "start" "1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee", 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" "1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee" "/opt/rustwide/cargo-home/bin/cargo" "+49a6044d37d694890450f52ceaceb66277a36b1e" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee", 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" "1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee" "/opt/rustwide/cargo-home/bin/cargo" "+49a6044d37d694890450f52ceaceb66277a36b1e" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stderr]     Checking too_many_linked_lists v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:112:23
[INFO] [stdout]     |
[INFO] [stdout] 112 |     pub fn peek_front(&self) -> Option<Ref< 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] 112 |     pub fn peek_front(&self) -> Option<Ref<'_,  T>> {
[INFO] [stdout]     |                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:118:22
[INFO] [stdout]     |
[INFO] [stdout] 118 |     pub fn peek_back(&self) -> Option<Ref<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] 118 |     pub fn peek_back(&self) -> Option<Ref<'_, T>> {
[INFO] [stdout]     |                                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:124:26
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn peek_back_mut(&mut self) -> Option<RefMut<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] 124 |     pub fn peek_back_mut(&mut self) -> Option<RefMut<'_, T>> {
[INFO] [stdout]     |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:130:27
[INFO] [stdout]     |
[INFO] [stdout] 130 |     pub fn peek_front_mut(&mut self) -> Option<RefMut<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] 130 |     pub fn peek_front_mut(&mut self) -> Option<RefMut<'_, T>> {
[INFO] [stdout]     |                                                       +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:112:23
[INFO] [stdout]     |
[INFO] [stdout] 112 |     pub fn peek_front(&self) -> Option<Ref< 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] 112 |     pub fn peek_front(&self) -> Option<Ref<'_,  T>> {
[INFO] [stdout]     |                                            +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:118:22
[INFO] [stdout]     |
[INFO] [stdout] 118 |     pub fn peek_back(&self) -> Option<Ref<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] 118 |     pub fn peek_back(&self) -> Option<Ref<'_, T>> {
[INFO] [stdout]     |                                           +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:124:26
[INFO] [stdout]     |
[INFO] [stdout] 124 |     pub fn peek_back_mut(&mut self) -> Option<RefMut<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] 124 |     pub fn peek_back_mut(&mut self) -> Option<RefMut<'_, T>> {
[INFO] [stdout]     |                                                      +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:130:27
[INFO] [stdout]     |
[INFO] [stdout] 130 |     pub fn peek_front_mut(&mut self) -> Option<RefMut<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] 130 |     pub fn peek_front_mut(&mut self) -> Option<RefMut<'_, T>> {
[INFO] [stdout]     |                                                       +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.22s
[INFO] running `Command { std: "docker" "inspect" "1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee", kill_on_drop: false }`
[INFO] [stdout] 1bc4c39e0a51825ab69218a6771bf5385eccb61f4cfd7a809e22115f2bf561ee
