[INFO] fetching crate unit15 0.1.0...
[INFO] building unit15-0.1.0 against master#ad85bc524b1ad696e42061ad8338d382dffbdbe5 for pr-146237-1
[INFO] extracting crate unit15 0.1.0 into /workspace/builds/worker-4-tc1/source
[INFO] started tweaking crates.io crate unit15 0.1.0
[INFO] finished tweaking crates.io crate unit15 0.1.0
[INFO] tweaked toml for crates.io crate unit15 0.1.0 written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate unit15 0.1.0 on toolchain ad85bc524b1ad696e42061ad8338d382dffbdbe5
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate unit15 0.1.0 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" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 21c58490f41d7001dfd046fa93f8dea4f66de0c22c8d039fa64ac52d45994f6c
[INFO] running `Command { std: "docker" "start" "-a" "21c58490f41d7001dfd046fa93f8dea4f66de0c22c8d039fa64ac52d45994f6c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "21c58490f41d7001dfd046fa93f8dea4f66de0c22c8d039fa64ac52d45994f6c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "21c58490f41d7001dfd046fa93f8dea4f66de0c22c8d039fa64ac52d45994f6c", kill_on_drop: false }`
[INFO] [stdout] 21c58490f41d7001dfd046fa93f8dea4f66de0c22c8d039fa64ac52d45994f6c
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 2b3e43e9b2b7ca09ccfd75783689382e06b0105488b0703604a6e3972be2390f
[INFO] running `Command { std: "docker" "start" "-a" "2b3e43e9b2b7ca09ccfd75783689382e06b0105488b0703604a6e3972be2390f", kill_on_drop: false }`
[INFO] [stderr]    Compiling unit15 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> src/main.rs:220:9
[INFO] [stdout]     |
[INFO] [stdout] 220 |     let a = Cons(1, Rc::clone(&rc_list));// 调用Rc::clone(&rc_list)，此处变量rc_list的引用计数为1
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> src/main.rs:223:13
[INFO] [stdout]     |
[INFO] [stdout] 223 |         let b = Cons(0, Rc::clone(&rc_list));// 调用Rc::clone(&rc_list)，此处变量rc_list的引用计数为2
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value` and `children` are never read
[INFO] [stdout]   --> src/main.rs:59:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |     struct Node {
[INFO] [stdout]    |            ---- fields in this struct
[INFO] [stdout] 59 |         value: i32,
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout] 60 |         parent: RefCell<Weak<Node>>,
[INFO] [stdout] 61 |         children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:89:14
[INFO] [stdout]    |
[INFO] [stdout] 89 |         Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout]    |         ---- ^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 89 -         Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout] 89 +         Cons((), RefCell<Rc<List>>),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]    --> src/main.rs:117:14
[INFO] [stdout]     |
[INFO] [stdout] 117 |         Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout]     |         ---- ^^^^^^^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         fields in this variant
[INFO] [stdout]     |
[INFO] [stdout]     = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]     |
[INFO] [stdout] 117 -         Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout] 117 +         Cons((), ()),
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `rc_smart_pointer` is never used
[INFO] [stdout]    --> src/main.rs:214:4
[INFO] [stdout]     |
[INFO] [stdout] 214 | fn rc_smart_pointer() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `1` is never read
[INFO] [stdout]    --> src/main.rs:287:13
[INFO] [stdout]     |
[INFO] [stdout] 287 |     Cons(T, Box<List<T>>),
[INFO] [stdout]     |     ----    ^^^^^^^^^^^^
[INFO] [stdout]     |     |
[INFO] [stdout]     |     field in this variant
[INFO] [stdout]     |
[INFO] [stdout]     = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]     |
[INFO] [stdout] 287 -     Cons(T, Box<List<T>>),
[INFO] [stdout] 287 +     Cons(T, ()),
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `RcList` is never used
[INFO] [stdout]    --> src/main.rs:292:6
[INFO] [stdout]     |
[INFO] [stdout] 292 | enum RcList<T> {
[INFO] [stdout]     |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.58s
[INFO] running `Command { std: "docker" "inspect" "2b3e43e9b2b7ca09ccfd75783689382e06b0105488b0703604a6e3972be2390f", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "2b3e43e9b2b7ca09ccfd75783689382e06b0105488b0703604a6e3972be2390f", kill_on_drop: false }`
[INFO] [stdout] 2b3e43e9b2b7ca09ccfd75783689382e06b0105488b0703604a6e3972be2390f
[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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ff6ab407541b2a7229adf02491a83a2a86423e6053326b4cb770bb1c5b6da045
[INFO] running `Command { std: "docker" "start" "-a" "ff6ab407541b2a7229adf02491a83a2a86423e6053326b4cb770bb1c5b6da045", kill_on_drop: false }`
[INFO] [stderr]    Compiling unit15 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]    --> src/main.rs:220:9
[INFO] [stdout]     |
[INFO] [stdout] 220 |     let a = Cons(1, Rc::clone(&rc_list));// 调用Rc::clone(&rc_list)，此处变量rc_list的引用计数为1
[INFO] [stdout]     |         ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout]     |
[INFO] [stdout]     = note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]    --> src/main.rs:223:13
[INFO] [stdout]     |
[INFO] [stdout] 223 |         let b = Cons(0, Rc::clone(&rc_list));// 调用Rc::clone(&rc_list)，此处变量rc_list的引用计数为2
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `value` and `children` are never read
[INFO] [stdout]   --> src/main.rs:59:9
[INFO] [stdout]    |
[INFO] [stdout] 58 |     struct Node {
[INFO] [stdout]    |            ---- fields in this struct
[INFO] [stdout] 59 |         value: i32,
[INFO] [stdout]    |         ^^^^^
[INFO] [stdout] 60 |         parent: RefCell<Weak<Node>>,
[INFO] [stdout] 61 |         children: RefCell<Vec<Rc<Node>>>,
[INFO] [stdout]    |         ^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `Node` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout]    = note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `0` is never read
[INFO] [stdout]   --> src/main.rs:89:14
[INFO] [stdout]    |
[INFO] [stdout] 89 |         Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout]    |         ---- ^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         field in this variant
[INFO] [stdout]    |
[INFO] [stdout]    = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]    |
[INFO] [stdout] 89 -         Cons(i32, RefCell<Rc<List>>),
[INFO] [stdout] 89 +         Cons((), RefCell<Rc<List>>),
[INFO] [stdout]    |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: fields `0` and `1` are never read
[INFO] [stdout]    --> src/main.rs:117:14
[INFO] [stdout]     |
[INFO] [stdout] 117 |         Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout]     |         ---- ^^^^^^^^^^^^^^^^  ^^^^^^^^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         fields in this variant
[INFO] [stdout]     |
[INFO] [stdout]     = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the fields to be of unit type to suppress this warning while preserving the field numbering, or remove the fields
[INFO] [stdout]     |
[INFO] [stdout] 117 -         Cons(Rc<RefCell<i32>>, Rc<List>),
[INFO] [stdout] 117 +         Cons((), ()),
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `rc_smart_pointer` is never used
[INFO] [stdout]    --> src/main.rs:214:4
[INFO] [stdout]     |
[INFO] [stdout] 214 | fn rc_smart_pointer() {
[INFO] [stdout]     |    ^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: field `1` is never read
[INFO] [stdout]    --> src/main.rs:287:13
[INFO] [stdout]     |
[INFO] [stdout] 287 |     Cons(T, Box<List<T>>),
[INFO] [stdout]     |     ----    ^^^^^^^^^^^^
[INFO] [stdout]     |     |
[INFO] [stdout]     |     field in this variant
[INFO] [stdout]     |
[INFO] [stdout]     = note: `List` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
[INFO] [stdout] help: consider changing the field to be of unit type to suppress this warning while preserving the field numbering, or remove the field
[INFO] [stdout]     |
[INFO] [stdout] 287 -     Cons(T, Box<List<T>>),
[INFO] [stdout] 287 +     Cons(T, ()),
[INFO] [stdout]     |
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: enum `RcList` is never used
[INFO] [stdout]    --> src/main.rs:292:6
[INFO] [stdout]     |
[INFO] [stdout] 292 | enum RcList<T> {
[INFO] [stdout]     |      ^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.52s
[INFO] running `Command { std: "docker" "inspect" "ff6ab407541b2a7229adf02491a83a2a86423e6053326b4cb770bb1c5b6da045", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ff6ab407541b2a7229adf02491a83a2a86423e6053326b4cb770bb1c5b6da045", kill_on_drop: false }`
[INFO] [stdout] ff6ab407541b2a7229adf02491a83a2a86423e6053326b4cb770bb1c5b6da045
