[INFO] cloning repository https://github.com/modulitos/programming-rust-book
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/modulitos/programming-rust-book" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2Fprogramming-rust-book", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2Fprogramming-rust-book'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1df18938c89c4f63579528fb8fddba6a20ae2082
[INFO] checking modulitos/programming-rust-book against master#d2eadb7a94ef8c9deb5137695df33cd1fc5aee92 for pr-137268
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fmodulitos%2Fprogramming-rust-book" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/modulitos/programming-rust-book on toolchain d2eadb7a94ef8c9deb5137695df33cd1fc5aee92
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+d2eadb7a94ef8c9deb5137695df33cd1fc5aee92" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/modulitos/programming-rust-book
[INFO] finished tweaking git repo https://github.com/modulitos/programming-rust-book
[INFO] tweaked toml for git repo https://github.com/modulitos/programming-rust-book written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/modulitos/programming-rust-book 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" "+d2eadb7a94ef8c9deb5137695df33cd1fc5aee92" "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-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+d2eadb7a94ef8c9deb5137695df33cd1fc5aee92" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a284e3334898d63871ee7e5e1dcafce5a91fa07a8aa9274ca207286ce43a6f15
[INFO] running `Command { std: "docker" "start" "-a" "a284e3334898d63871ee7e5e1dcafce5a91fa07a8aa9274ca207286ce43a6f15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a284e3334898d63871ee7e5e1dcafce5a91fa07a8aa9274ca207286ce43a6f15", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a284e3334898d63871ee7e5e1dcafce5a91fa07a8aa9274ca207286ce43a6f15", kill_on_drop: false }`
[INFO] [stdout] a284e3334898d63871ee7e5e1dcafce5a91fa07a8aa9274ca207286ce43a6f15
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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:b0b074c097205a61b89e8ad263052f976b2b332c4dc5f02aef1fe52501660d6e" "/opt/rustwide/cargo-home/bin/cargo" "+d2eadb7a94ef8c9deb5137695df33cd1fc5aee92" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 68b5adea79ea948808ecc878c4c72f807daac76e0acd934972beeaae2e660588
[INFO] running `Command { std: "docker" "start" "-a" "68b5adea79ea948808ecc878c4c72f807daac76e0acd934972beeaae2e660588", kill_on_drop: false }`
[INFO] [stderr]     Checking programming_rust_book v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:11:22
[INFO] [stdout]    |
[INFO] [stdout] 11 |     fn splice(&self, other: &Self) -> Self {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:11:22
[INFO] [stdout]    |
[INFO] [stdout] 11 |     fn splice(&self, other: &Self) -> Self {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:20:22
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fn splice(&self, other: &Self) -> Self {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:37:22
[INFO] [stdout]    |
[INFO] [stdout] 37 |     fn splice(&self, other: &dyn MegaSpliceable) -> Box<dyn MegaSpliceable> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:44:22
[INFO] [stdout]    |
[INFO] [stdout] 44 |     fn splice(&self, other: &dyn MegaSpliceable) -> Box<dyn MegaSpliceable> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `words`
[INFO] [stdout]   --> src/ch_11.rs:53:9
[INFO] [stdout]    |
[INFO] [stdout] 53 |     let words: Vec<String> = line
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_words`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:20:22
[INFO] [stdout]    |
[INFO] [stdout] 20 |     fn splice(&self, other: &Self) -> Self {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:37:22
[INFO] [stdout]    |
[INFO] [stdout] 37 |     fn splice(&self, other: &dyn MegaSpliceable) -> Box<dyn MegaSpliceable> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `other`
[INFO] [stdout]   --> src/ch_11.rs:44:22
[INFO] [stdout]    |
[INFO] [stdout] 44 |     fn splice(&self, other: &dyn MegaSpliceable) -> Box<dyn MegaSpliceable> {
[INFO] [stdout]    |                      ^^^^^ help: if this is intentional, prefix it with an underscore: `_other`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `words`
[INFO] [stdout]   --> src/ch_11.rs:53:9
[INFO] [stdout]    |
[INFO] [stdout] 53 |     let words: Vec<String> = line
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_words`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Spliceable` is never used
[INFO] [stdout]  --> src/ch_11.rs:4:11
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub trait Spliceable {
[INFO] [stdout]   |           ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `CherryTree` is never constructed
[INFO] [stdout]  --> src/ch_11.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct CherryTree {}
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Mammoth` is never constructed
[INFO] [stdout]   --> src/ch_11.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | struct Mammoth {}
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `MegaSpliceable` is never used
[INFO] [stdout]   --> src/ch_11.rs:32:11
[INFO] [stdout]    |
[INFO] [stdout] 32 | pub trait MegaSpliceable {
[INFO] [stdout]    |           ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_fqmc` is never used
[INFO] [stdout]   --> src/ch_11.rs:51:4
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn test_fqmc() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Spliceable` is never used
[INFO] [stdout]  --> src/ch_11.rs:4:11
[INFO] [stdout]   |
[INFO] [stdout] 4 | pub trait Spliceable {
[INFO] [stdout]   |           ^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `CherryTree` is never constructed
[INFO] [stdout]  --> src/ch_11.rs:8:8
[INFO] [stdout]   |
[INFO] [stdout] 8 | struct CherryTree {}
[INFO] [stdout]   |        ^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `Mammoth` is never constructed
[INFO] [stdout]   --> src/ch_11.rs:17:8
[INFO] [stdout]    |
[INFO] [stdout] 17 | struct Mammoth {}
[INFO] [stdout]    |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `MegaSpliceable` is never used
[INFO] [stdout]   --> src/ch_11.rs:32:11
[INFO] [stdout]    |
[INFO] [stdout] 32 | pub trait MegaSpliceable {
[INFO] [stdout]    |           ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `test_fqmc` is never used
[INFO] [stdout]   --> src/ch_11.rs:51:4
[INFO] [stdout]    |
[INFO] [stdout] 51 | fn test_fqmc() {
[INFO] [stdout]    |    ^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `dump` is never used
[INFO] [stdout]   --> src/ch_11.rs:74:4
[INFO] [stdout]    |
[INFO] [stdout] 74 | fn dump<I>(iter: I)
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Pattern` is never used
[INFO] [stdout]   --> src/ch_11.rs:88:7
[INFO] [stdout]    |
[INFO] [stdout] 88 | trait Pattern {
[INFO] [stdout]    |       ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `rand` is never used
[INFO] [stdout]    --> src/ch_11.rs:131:8
[INFO] [stdout]     |
[INFO] [stdout] 126 | pub trait Rand: Sized {
[INFO] [stdout]     |           ---- associated function in this trait
[INFO] [stdout] ...
[INFO] [stdout] 131 |     fn rand<R: Rng>(rng: &mut R) -> Self;
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SomeRng` is never constructed
[INFO] [stdout]    --> src/ch_11.rs:136:8
[INFO] [stdout]     |
[INFO] [stdout] 136 | struct SomeRng {}
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `dump` is never used
[INFO] [stdout]   --> src/ch_11.rs:74:4
[INFO] [stdout]    |
[INFO] [stdout] 74 | fn dump<I>(iter: I)
[INFO] [stdout]    |    ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: trait `Pattern` is never used
[INFO] [stdout]   --> src/ch_11.rs:88:7
[INFO] [stdout]    |
[INFO] [stdout] 88 | trait Pattern {
[INFO] [stdout]    |       ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function `rand` is never used
[INFO] [stdout]    --> src/ch_11.rs:131:8
[INFO] [stdout]     |
[INFO] [stdout] 126 | pub trait Rand: Sized {
[INFO] [stdout]     |           ---- associated function in this trait
[INFO] [stdout] ...
[INFO] [stdout] 131 |     fn rand<R: Rng>(rng: &mut R) -> Self;
[INFO] [stdout]     |        ^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: struct `SomeRng` is never constructed
[INFO] [stdout]    --> src/ch_11.rs:136:8
[INFO] [stdout]     |
[INFO] [stdout] 136 | struct SomeRng {}
[INFO] [stdout]     |        ^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.06s
[INFO] running `Command { std: "docker" "inspect" "68b5adea79ea948808ecc878c4c72f807daac76e0acd934972beeaae2e660588", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "68b5adea79ea948808ecc878c4c72f807daac76e0acd934972beeaae2e660588", kill_on_drop: false }`
[INFO] [stdout] 68b5adea79ea948808ecc878c4c72f807daac76e0acd934972beeaae2e660588