[INFO] cloning repository https://github.com/primi-duan/dlink_list
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/primi-duan/dlink_list" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprimi-duan%2Fdlink_list", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprimi-duan%2Fdlink_list'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 633bbc95d1d3bd2fa0dda94ca9eb528bf61dd201
[INFO] checking primi-duan/dlink_list against master#350d0ef0ec0493e6d21cfb265cb8211a0e74d766 for pr-145342-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fprimi-duan%2Fdlink_list" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/primi-duan/dlink_list
[INFO] finished tweaking git repo https://github.com/primi-duan/dlink_list
[INFO] tweaked toml for git repo https://github.com/primi-duan/dlink_list written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/primi-duan/dlink_list on toolchain 350d0ef0ec0493e6d21cfb265cb8211a0e74d766
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/primi-duan/dlink_list 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" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 50353b57b6fd39141777e3e26cfaae8a49822adf36372ca5a39c8d7922d10096
[INFO] running `Command { std: "docker" "start" "-a" "50353b57b6fd39141777e3e26cfaae8a49822adf36372ca5a39c8d7922d10096", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "50353b57b6fd39141777e3e26cfaae8a49822adf36372ca5a39c8d7922d10096", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "50353b57b6fd39141777e3e26cfaae8a49822adf36372ca5a39c8d7922d10096", kill_on_drop: false }`
[INFO] [stdout] 50353b57b6fd39141777e3e26cfaae8a49822adf36372ca5a39c8d7922d10096
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/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@sha256:7ad1b28ee6f5f7f699f6cf7015098d6ccdd96d6f2d78dd06228f5b4c9faf309c" "/opt/rustwide/cargo-home/bin/cargo" "+350d0ef0ec0493e6d21cfb265cb8211a0e74d766" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 369996e8b84595b1a906f8ffefbc06bdaabd1f4740500a2d4fc3e64f0e5c1142
[INFO] running `Command { std: "docker" "start" "-a" "369996e8b84595b1a906f8ffefbc06bdaabd1f4740500a2d4fc3e64f0e5c1142", kill_on_drop: false }`
[INFO] [stderr]     Checking link_list_test v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: type `Node_st` should have an upper camel case name
[INFO] [stdout]   --> src/dlink_list.rs:14:12
[INFO] [stdout]    |
[INFO] [stdout] 14 |     struct Node_st<T: Display> {
[INFO] [stdout]    |            ^^^^^^^ help: convert the identifier to upper camel case: `NodeSt`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: type `Node_st` should have an upper camel case name
[INFO] [stdout]   --> src/dlink_list.rs:14:12
[INFO] [stdout]    |
[INFO] [stdout] 14 |     struct Node_st<T: Display> {
[INFO] [stdout]    |            ^^^^^^^ help: convert the identifier to upper camel case: `NodeSt`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(non_camel_case_types)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `DLINK_LIST` should have a snake case name
[INFO] [stdout]  --> src/dlink_list.rs:1:9
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub mod DLINK_LIST {
[INFO] [stdout]   |         ^^^^^^^^^^ help: convert the identifier to snake case: `dlink_list`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:41:13
[INFO] [stdout]    |
[INFO] [stdout] 41 |             write!(f, "------------show list------------\n");
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 41 |             let _ = write!(f, "------------show list------------\n");
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:42:13
[INFO] [stdout]    |
[INFO] [stdout] 42 |             write!(f, "length: {}\n", self.len);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 42 |             let _ = write!(f, "length: {}\n", self.len);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:43:13
[INFO] [stdout]    |
[INFO] [stdout] 43 |             write!(f, "capacity: {}\n", self.capacity);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 43 |             let _ = write!(f, "capacity: {}\n", self.capacity);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:45:17
[INFO] [stdout]    |
[INFO] [stdout] 45 |                 write!(f, "[empty]");
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 45 |                 let _ = write!(f, "[empty]");
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:51:13
[INFO] [stdout]    |
[INFO] [stdout] 51 |             write!(f, "node value {}", tmp_head.borrow().element);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 51 |             let _ = write!(f, "node value {}", tmp_head.borrow().element);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:54:17
[INFO] [stdout]    |
[INFO] [stdout] 54 |                 write!(f, " -> ");
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 54 |                 let _ = write!(f, " -> ");
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:56:17
[INFO] [stdout]    |
[INFO] [stdout] 56 |                 write!(f, "node value {}", next_t.borrow().element);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 56 |                 let _ = write!(f, "node value {}", next_t.borrow().element);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/dlink_list.rs:146:29
[INFO] [stdout]     |
[INFO] [stdout] 146 |         pub fn peek_at_head(&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] 146 |         pub fn peek_at_head(&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/dlink_list.rs:234:29
[INFO] [stdout]     |
[INFO] [stdout] 234 |         pub fn peek_at_tail(&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] 234 |         pub fn peek_at_tail(&self) -> Option<Ref<'_, T>> {
[INFO] [stdout]     |                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: module `DLINK_LIST` should have a snake case name
[INFO] [stdout]  --> src/dlink_list.rs:1:9
[INFO] [stdout]   |
[INFO] [stdout] 1 | pub mod DLINK_LIST {
[INFO] [stdout]   |         ^^^^^^^^^^ help: convert the identifier to snake case: `dlink_list`
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(non_snake_case)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:41:13
[INFO] [stdout]    |
[INFO] [stdout] 41 |             write!(f, "------------show list------------\n");
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 41 |             let _ = write!(f, "------------show list------------\n");
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:42:13
[INFO] [stdout]    |
[INFO] [stdout] 42 |             write!(f, "length: {}\n", self.len);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 42 |             let _ = write!(f, "length: {}\n", self.len);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:43:13
[INFO] [stdout]    |
[INFO] [stdout] 43 |             write!(f, "capacity: {}\n", self.capacity);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 43 |             let _ = write!(f, "capacity: {}\n", self.capacity);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:45:17
[INFO] [stdout]    |
[INFO] [stdout] 45 |                 write!(f, "[empty]");
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 45 |                 let _ = write!(f, "[empty]");
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:51:13
[INFO] [stdout]    |
[INFO] [stdout] 51 |             write!(f, "node value {}", tmp_head.borrow().element);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 51 |             let _ = write!(f, "node value {}", tmp_head.borrow().element);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:54:17
[INFO] [stdout]    |
[INFO] [stdout] 54 |                 write!(f, " -> ");
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 54 |                 let _ = write!(f, " -> ");
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused `Result` that must be used
[INFO] [stdout]   --> src/dlink_list.rs:56:17
[INFO] [stdout]    |
[INFO] [stdout] 56 |                 write!(f, "node value {}", next_t.borrow().element);
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: this `Result` may be an `Err` variant, which should be handled
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 56 |                 let _ = write!(f, "node value {}", next_t.borrow().element);
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: hiding a lifetime that's elided elsewhere is confusing
[INFO] [stdout]    --> src/dlink_list.rs:146:29
[INFO] [stdout]     |
[INFO] [stdout] 146 |         pub fn peek_at_head(&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] 146 |         pub fn peek_at_head(&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/dlink_list.rs:234:29
[INFO] [stdout]     |
[INFO] [stdout] 234 |         pub fn peek_at_tail(&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] 234 |         pub fn peek_at_tail(&self) -> Option<Ref<'_, T>> {
[INFO] [stdout]     |                                                  +++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.32s
[INFO] running `Command { std: "docker" "inspect" "369996e8b84595b1a906f8ffefbc06bdaabd1f4740500a2d4fc3e64f0e5c1142", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "369996e8b84595b1a906f8ffefbc06bdaabd1f4740500a2d4fc3e64f0e5c1142", kill_on_drop: false }`
[INFO] [stdout] 369996e8b84595b1a906f8ffefbc06bdaabd1f4740500a2d4fc3e64f0e5c1142