[INFO] cloning repository https://github.com/amitdash291/rust_lifetimes
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/amitdash291/rust_lifetimes" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famitdash291%2Frust_lifetimes", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famitdash291%2Frust_lifetimes'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1de31b9f2321d84ba42e1c3319e2142917794fe9
[INFO] checking amitdash291/rust_lifetimes against master#33fdb797f59421c7bbecaa4588ed5d7a31a9494a for pr-87190-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famitdash291%2Frust_lifetimes" "/workspace/builds/worker-38/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-38/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/amitdash291/rust_lifetimes on toolchain 33fdb797f59421c7bbecaa4588ed5d7a31a9494a
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/amitdash291/rust_lifetimes
[INFO] finished tweaking git repo https://github.com/amitdash291/rust_lifetimes
[INFO] tweaked toml for git repo https://github.com/amitdash291/rust_lifetimes written to /workspace/builds/worker-38/source/Cargo.toml
[INFO] crate git repo https://github.com/amitdash291/rust_lifetimes already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 5bc59c5bd81639c2a7f9d8da1c4e13456500b4755150e8c1de74b5ed6b2a3c52
[INFO] running `Command { std: "docker" "start" "-a" "5bc59c5bd81639c2a7f9d8da1c4e13456500b4755150e8c1de74b5ed6b2a3c52", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "5bc59c5bd81639c2a7f9d8da1c4e13456500b4755150e8c1de74b5ed6b2a3c52", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "5bc59c5bd81639c2a7f9d8da1c4e13456500b4755150e8c1de74b5ed6b2a3c52", kill_on_drop: false }`
[INFO] [stdout] 5bc59c5bd81639c2a7f9d8da1c4e13456500b4755150e8c1de74b5ed6b2a3c52
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-38/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" "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@sha256:34b6a614d2c27851fe6cbf88fbd1137609cefab8b10d0615aaeb6fd47975d74e" "/opt/rustwide/cargo-home/bin/cargo" "+33fdb797f59421c7bbecaa4588ed5d7a31a9494a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a15969c8f148afca14e1c37e3b83f2c4ba160e46c53b0b676f36b818388991f6
[INFO] running `Command { std: "docker" "start" "-a" "a15969c8f148afca14e1c37e3b83f2c4ba160e46c53b0b676f36b818388991f6", kill_on_drop: false }`
[INFO] [stderr]     Checking lifetime_demo v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable `result_ref` is assigned to, but never used
[INFO] [stdout]  --> src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let result_ref;
[INFO] [stdout]   |         ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]   = note: consider using `_result_ref` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable `result_ref` is assigned to, but never used
[INFO] [stdout]  --> src/main.rs:4:9
[INFO] [stdout]   |
[INFO] [stdout] 4 |     let result_ref;
[INFO] [stdout]   |         ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout]   = note: consider using `_result_ref` instead
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `result_ref` is never read
[INFO] [stdout]  --> src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     result_ref = which_is_greater(&a, &b)
[INFO] [stdout]   |     ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:25:29
[INFO] [stdout]    |
[INFO] [stdout] 25 | fn which_is_greater<'a, 'b>(a: &'a i32, b: &'b i32) -> &'b i32 {
[INFO] [stdout]    |                             ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: value assigned to `result_ref` is never read
[INFO] [stdout]  --> src/main.rs:6:5
[INFO] [stdout]   |
[INFO] [stdout] 6 |     result_ref = which_is_greater(&a, &b)
[INFO] [stdout]   |     ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_assignments)]` on by default
[INFO] [stdout]   = help: maybe it is overwritten before being read?
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `a`
[INFO] [stdout]   --> src/main.rs:25:29
[INFO] [stdout]    |
[INFO] [stdout] 25 | fn which_is_greater<'a, 'b>(a: &'a i32, b: &'b i32) -> &'b i32 {
[INFO] [stdout]    |                             ^ help: if this is intentional, prefix it with an underscore: `_a`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/main.rs:25:41
[INFO] [stdout]    |
[INFO] [stdout] 25 | fn which_is_greater<'a, 'b>(a: &'a i32, b: &'b i32) -> &'b i32 {
[INFO] [stdout]    |                                         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `vec1`
[INFO] [stdout]   --> src/main.rs:37:13
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut vec1: Vec<i32> = Vec::new();
[INFO] [stdout]    |             ^^^^ help: if this is intentional, prefix it with an underscore: `_vec1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `b`
[INFO] [stdout]   --> src/main.rs:25:41
[INFO] [stdout]    |
[INFO] [stdout] 25 | fn which_is_greater<'a, 'b>(a: &'a i32, b: &'b i32) -> &'b i32 {
[INFO] [stdout]    |                                         ^ help: if this is intentional, prefix it with an underscore: `_b`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `vec1`
[INFO] [stdout]   --> src/main.rs:37:13
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut vec1: Vec<i32> = Vec::new();
[INFO] [stdout]    |             ^^^^ help: if this is intentional, prefix it with an underscore: `_vec1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut vec1: Vec<i32> = Vec::new();
[INFO] [stdout]    |         ----^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:37:9
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut vec1: Vec<i32> = Vec::new();
[INFO] [stdout]    |         ----^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_mut)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_mut_ref`
[INFO] [stdout]   --> src/main.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn test_mut_ref() {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_mut_ref`
[INFO] [stdout]   --> src/main.rs:34:4
[INFO] [stdout]    |
[INFO] [stdout] 34 | fn test_mut_ref() {
[INFO] [stdout]    |    ^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `copy_vec`
[INFO] [stdout]   --> src/main.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn copy_vec(from: &Vec<i32>, to: &mut Vec<i32>) {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `copy_vec`
[INFO] [stdout]   --> src/main.rs:40:4
[INFO] [stdout]    |
[INFO] [stdout] 40 | fn copy_vec(from: &Vec<i32>, to: &mut Vec<i32>) {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 8 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.13s
[INFO] running `Command { std: "docker" "inspect" "a15969c8f148afca14e1c37e3b83f2c4ba160e46c53b0b676f36b818388991f6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a15969c8f148afca14e1c37e3b83f2c4ba160e46c53b0b676f36b818388991f6", kill_on_drop: false }`
[INFO] [stdout] a15969c8f148afca14e1c37e3b83f2c4ba160e46c53b0b676f36b818388991f6