[INFO] cloning repository https://github.com/shanemikel/rust-hello
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/shanemikel/rust-hello" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshanemikel%2Frust-hello", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshanemikel%2Frust-hello'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] d473b3db08dbfe0ed83f428a13e337b242c04ce5
[INFO] checking shanemikel/rust-hello against try#f47dd4da3ae8c32c9e65d307bfe640b143e674df for pr-77526
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fshanemikel%2Frust-hello" "/workspace/builds/worker-11/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-11/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/shanemikel/rust-hello on toolchain f47dd4da3ae8c32c9e65d307bfe640b143e674df
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/shanemikel/rust-hello
[INFO] finished tweaking git repo https://github.com/shanemikel/rust-hello
[INFO] tweaked toml for git repo https://github.com/shanemikel/rust-hello written to /workspace/builds/worker-11/source/Cargo.toml
[INFO] crate git repo https://github.com/shanemikel/rust-hello already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] cf1ee9cc9fc091f01aa9d5c05ef92bfe0fe3a9944a976cd8b6cb2ba1c22a3437
[INFO] running `Command { std: "docker" "start" "-a" "cf1ee9cc9fc091f01aa9d5c05ef92bfe0fe3a9944a976cd8b6cb2ba1c22a3437", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "cf1ee9cc9fc091f01aa9d5c05ef92bfe0fe3a9944a976cd8b6cb2ba1c22a3437", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "cf1ee9cc9fc091f01aa9d5c05ef92bfe0fe3a9944a976cd8b6cb2ba1c22a3437", kill_on_drop: false }`
[INFO] [stdout] cf1ee9cc9fc091f01aa9d5c05ef92bfe0fe3a9944a976cd8b6cb2ba1c22a3437
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-11/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" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+f47dd4da3ae8c32c9e65d307bfe640b143e674df" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 54229f26e99a6fda83a5e53f31786d6cce945001c880f1204847856ab0c96ffb
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "54229f26e99a6fda83a5e53f31786d6cce945001c880f1204847856ab0c96ffb", kill_on_drop: false }`
[INFO] [stderr]     Checking rust-hello v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::cell::RefCell`
[INFO] [stdout]  --> src/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     use std::cell::RefCell;
[INFO] [stdout]   |         ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Mutex`
[INFO] [stdout]  --> src/main.rs:9:26
[INFO] [stdout]   |
[INFO] [stdout] 9 |     use std::sync::{Arc, Mutex, RwLock};
[INFO] [stdout]   |                          ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `std::cell::RefCell`
[INFO] [stdout]  --> src/main.rs:8:9
[INFO] [stdout]   |
[INFO] [stdout] 8 |     use std::cell::RefCell;
[INFO] [stdout]   |         ^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused import: `Mutex`
[INFO] [stdout]  --> src/main.rs:9:26
[INFO] [stdout]   |
[INFO] [stdout] 9 |     use std::sync::{Arc, Mutex, RwLock};
[INFO] [stdout]   |                          ^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]   --> src/main.rs:25:17
[INFO] [stdout]    |
[INFO] [stdout] 25 |             let data = data.read().unwrap();
[INFO] [stdout]    |                 ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `data`
[INFO] [stdout]   --> src/main.rs:25:17
[INFO] [stdout]    |
[INFO] [stdout] 25 |             let data = data.read().unwrap();
[INFO] [stdout]    |                 ^^^^ help: if this is intentional, prefix it with an underscore: `_data`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Cons`
[INFO] [stdout]  --> src/list.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     Cons(T, Box<List<T>>),
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nil`
[INFO] [stdout]  --> src/list.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Nil,
[INFO] [stdout]   |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]  --> src/list.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub fn new() -> List<T> { List::Nil }
[INFO] [stdout]   |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `cons`
[INFO] [stdout]   --> src/list.rs:11:12
[INFO] [stdout]    |
[INFO] [stdout] 11 |     pub fn cons(self, x: T) -> List<T> { List::Cons(x, Box::new(self)) }
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `head`
[INFO] [stdout]   --> src/list.rs:13:12
[INFO] [stdout]    |
[INFO] [stdout] 13 |     pub fn head(self) -> Option<T> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `tail`
[INFO] [stdout]   --> src/list.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 |     pub fn tail(&self) -> Option<&List<T>> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `head_ref`
[INFO] [stdout]   --> src/list.rs:29:12
[INFO] [stdout]    |
[INFO] [stdout] 29 |     pub fn head_ref(&self) -> Option<T> {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `N`
[INFO] [stdout]   --> src/main.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     const N: usize = 10;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_list`
[INFO] [stdout]   --> src/main.rs:39:4
[INFO] [stdout]    |
[INFO] [stdout] 39 | fn test_list() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Cons`
[INFO] [stdout]  --> src/list.rs:4:5
[INFO] [stdout]   |
[INFO] [stdout] 4 |     Cons(T, Box<List<T>>),
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variant is never constructed: `Nil`
[INFO] [stdout]  --> src/list.rs:5:5
[INFO] [stdout]   |
[INFO] [stdout] 5 |     Nil,
[INFO] [stdout]   |     ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `new`
[INFO] [stdout]  --> src/list.rs:9:12
[INFO] [stdout]   |
[INFO] [stdout] 9 |     pub fn new() -> List<T> { List::Nil }
[INFO] [stdout]   |            ^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `cons`
[INFO] [stdout]   --> src/list.rs:11:12
[INFO] [stdout]    |
[INFO] [stdout] 11 |     pub fn cons(self, x: T) -> List<T> { List::Cons(x, Box::new(self)) }
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `head`
[INFO] [stdout]   --> src/list.rs:13:12
[INFO] [stdout]    |
[INFO] [stdout] 13 |     pub fn head(self) -> Option<T> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `tail`
[INFO] [stdout]   --> src/list.rs:20:12
[INFO] [stdout]    |
[INFO] [stdout] 20 |     pub fn tail(&self) -> Option<&List<T>> {
[INFO] [stdout]    |            ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `head_ref`
[INFO] [stdout]   --> src/list.rs:29:12
[INFO] [stdout]    |
[INFO] [stdout] 29 |     pub fn head_ref(&self) -> Option<T> {
[INFO] [stdout]    |            ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: constant is never used: `N`
[INFO] [stdout]   --> src/main.rs:13:5
[INFO] [stdout]    |
[INFO] [stdout] 13 |     const N: usize = 10;
[INFO] [stdout]    |     ^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function is never used: `test_list`
[INFO] [stdout]   --> src/main.rs:39:4
[INFO] [stdout]    |
[INFO] [stdout] 39 | fn test_list() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 12 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.50s
[INFO] running `Command { std: "docker" "inspect" "54229f26e99a6fda83a5e53f31786d6cce945001c880f1204847856ab0c96ffb", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "54229f26e99a6fda83a5e53f31786d6cce945001c880f1204847856ab0c96ffb", kill_on_drop: false }`
[INFO] [stdout] 54229f26e99a6fda83a5e53f31786d6cce945001c880f1204847856ab0c96ffb