[INFO] cloning repository https://github.com/kvago36/lists
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kvago36/lists" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkvago36%2Flists", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkvago36%2Flists'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 92452b889d60c87d2109b24e5dfc9fa708220415
[INFO] checking kvago36/lists against try#943e2200e35c3825486c4671b6cab0107a07f8c1 for pr-148952
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkvago36%2Flists" "/workspace/builds/worker-0-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-0-tc2/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/kvago36/lists
[INFO] finished tweaking git repo https://github.com/kvago36/lists
[INFO] tweaked toml for git repo https://github.com/kvago36/lists written to /workspace/builds/worker-0-tc2/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/kvago36/lists on toolchain 943e2200e35c3825486c4671b6cab0107a07f8c1
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/kvago36/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" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "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-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] bcd20efabf895147d6f6f1f5fe77c68f3a6bb29e882928912ac2bd6a95a3ecc6
[INFO] running `Command { std: "docker" "start" "-a" "bcd20efabf895147d6f6f1f5fe77c68f3a6bb29e882928912ac2bd6a95a3ecc6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "bcd20efabf895147d6f6f1f5fe77c68f3a6bb29e882928912ac2bd6a95a3ecc6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "bcd20efabf895147d6f6f1f5fe77c68f3a6bb29e882928912ac2bd6a95a3ecc6", kill_on_drop: false }`
[INFO] [stdout] bcd20efabf895147d6f6f1f5fe77c68f3a6bb29e882928912ac2bd6a95a3ecc6
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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@sha256:4848fb76d95f26979359cc7e45710b1dbc8f3acb7aeedee7c460d7702230f228" "/opt/rustwide/cargo-home/bin/cargo" "+943e2200e35c3825486c4671b6cab0107a07f8c1" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] e6c05f3e5a23ec247edcbcdf0efe01cc9a8d6450aa11f860031888a9e7c01995
[INFO] running `Command { std: "docker" "start" "-a" "e6c05f3e5a23ec247edcbcdf0efe01cc9a8d6450aa11f860031888a9e7c01995", kill_on_drop: false }`
[INFO] [stderr]     Checking lists v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/fourth.rs:125:23
[INFO] [stdout]     |
[INFO] [stdout] 125 |     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] 125 |     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:147:22
[INFO] [stdout]     |
[INFO] [stdout] 147 |     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] 147 |     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:153:26
[INFO] [stdout]     |
[INFO] [stdout] 153 |     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] 153 |     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:159:27
[INFO] [stdout]     |
[INFO] [stdout] 159 |     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] 159 |     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:125:23
[INFO] [stdout]     |
[INFO] [stdout] 125 |     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] 125 |     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:147:22
[INFO] [stdout]     |
[INFO] [stdout] 147 |     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] 147 |     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:153:26
[INFO] [stdout]     |
[INFO] [stdout] 153 |     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] 153 |     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:159:27
[INFO] [stdout]     |
[INFO] [stdout] 159 |     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] 159 |     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 0.15s
[INFO] running `Command { std: "docker" "inspect" "e6c05f3e5a23ec247edcbcdf0efe01cc9a8d6450aa11f860031888a9e7c01995", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "e6c05f3e5a23ec247edcbcdf0efe01cc9a8d6450aa11f860031888a9e7c01995", kill_on_drop: false }`
[INFO] [stdout] e6c05f3e5a23ec247edcbcdf0efe01cc9a8d6450aa11f860031888a9e7c01995
