[INFO] fetching crate unit8 0.1.0...
[INFO] building unit8-0.1.0 against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] extracting crate unit8 0.1.0 into /workspace/builds/worker-7-tc1/source
[INFO] validating manifest of crates.io crate unit8 0.1.0 on toolchain 11663cd3bfefef7d34e8f0892c250bf698049392
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate unit8 0.1.0
[INFO] finished tweaking crates.io crate unit8 0.1.0
[INFO] tweaked toml for crates.io crate unit8 0.1.0 written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate crates.io crate unit8 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" "+11663cd3bfefef7d34e8f0892c250bf698049392" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] f98facd3ebc3be28c0effa8a88539741a5eeab73ea1927964aa5b0313526c79c
[INFO] running `Command { std: "docker" "start" "-a" "f98facd3ebc3be28c0effa8a88539741a5eeab73ea1927964aa5b0313526c79c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "f98facd3ebc3be28c0effa8a88539741a5eeab73ea1927964aa5b0313526c79c", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f98facd3ebc3be28c0effa8a88539741a5eeab73ea1927964aa5b0313526c79c", kill_on_drop: false }`
[INFO] [stdout] f98facd3ebc3be28c0effa8a88539741a5eeab73ea1927964aa5b0313526c79c
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f5e438328848f77baf6dfe9864e1bf96de5765b2180eb8efa93a1cc76e1321b2
[INFO] running `Command { std: "docker" "start" "-a" "f5e438328848f77baf6dfe9864e1bf96de5765b2180eb8efa93a1cc76e1321b2", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.147
[INFO] [stderr]    Compiling rand v0.4.6
[INFO] [stderr]    Compiling rand v0.3.23
[INFO] [stderr]    Compiling unit8 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::fmt::Debug`
[INFO] [stdout]  --> src/main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::fmt::Debug;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     for i in 0..100 {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `index0`
[INFO] [stdout]   --> src/main.rs:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let index0 = &list[0];
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_index0`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `index1`
[INFO] [stdout]   --> src/main.rs:53:17
[INFO] [stdout]    |
[INFO] [stdout] 53 |     if let Some(index1) = index1_option {} else {}
[INFO] [stdout]    |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_index1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `string`
[INFO] [stdout]   --> src/main.rs:66:9
[INFO] [stdout]    |
[INFO] [stdout] 66 |     let string = String::new();
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `string`
[INFO] [stdout]   --> src/main.rs:68:9
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let string = String::from("string");
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `new_s`
[INFO] [stdout]   --> src/main.rs:84:9
[INFO] [stdout]    |
[INFO] [stdout] 84 |     let new_s = format!("{}-{}", new_s, s);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_new_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `k`
[INFO] [stdout]    --> src/main.rs:108:10
[INFO] [stdout]     |
[INFO] [stdout] 108 |     for (k, v) in map {}
[INFO] [stdout]     |          ^ help: if this is intentional, prefix it with an underscore: `_k`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:108:13
[INFO] [stdout]     |
[INFO] [stdout] 108 |     for (k, v) in map {}
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `vec` is never used
[INFO] [stdout]   --> src/main.rs:39:4
[INFO] [stdout]    |
[INFO] [stdout] 39 | fn vec() {
[INFO] [stdout]    |    ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `str_and_string` is never used
[INFO] [stdout]   --> src/main.rs:62:4
[INFO] [stdout]    |
[INFO] [stdout] 62 | fn str_and_string() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hash_map` is never used
[INFO] [stdout]   --> src/main.rs:88:4
[INFO] [stdout]    |
[INFO] [stdout] 88 | fn hash_map() {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.92s
[INFO] running `Command { std: "docker" "inspect" "f5e438328848f77baf6dfe9864e1bf96de5765b2180eb8efa93a1cc76e1321b2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f5e438328848f77baf6dfe9864e1bf96de5765b2180eb8efa93a1cc76e1321b2", kill_on_drop: false }`
[INFO] [stdout] f5e438328848f77baf6dfe9864e1bf96de5765b2180eb8efa93a1cc76e1321b2
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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 -Dtail-expr-drop-order" "-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:f3a9d4ad9d972b27faf3965f35b62e55ba32bbce8f20bc8fe909558a86702fde" "/opt/rustwide/cargo-home/bin/cargo" "+11663cd3bfefef7d34e8f0892c250bf698049392" "test" "--frozen" "--no-run" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 095e1196355ce8a1c855dbc60f5cfa17c19fb06fcd9eebbab664c5bc688dcf52
[INFO] running `Command { std: "docker" "start" "-a" "095e1196355ce8a1c855dbc60f5cfa17c19fb06fcd9eebbab664c5bc688dcf52", kill_on_drop: false }`
[INFO] [stderr]    Compiling unit8 v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused import: `std::fmt::Debug`
[INFO] [stdout]  --> src/main.rs:2:5
[INFO] [stdout]   |
[INFO] [stdout] 2 | use std::fmt::Debug;
[INFO] [stdout]   |     ^^^^^^^^^^^^^^^
[INFO] [stdout]   |
[INFO] [stdout]   = note: `#[warn(unused_imports)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `i`
[INFO] [stdout]   --> src/main.rs:12:9
[INFO] [stdout]    |
[INFO] [stdout] 12 |     for i in 0..100 {
[INFO] [stdout]    |         ^ help: if this is intentional, prefix it with an underscore: `_i`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `index0`
[INFO] [stdout]   --> src/main.rs:50:9
[INFO] [stdout]    |
[INFO] [stdout] 50 |     let index0 = &list[0];
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_index0`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `index1`
[INFO] [stdout]   --> src/main.rs:53:17
[INFO] [stdout]    |
[INFO] [stdout] 53 |     if let Some(index1) = index1_option {} else {}
[INFO] [stdout]    |                 ^^^^^^ help: if this is intentional, prefix it with an underscore: `_index1`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `string`
[INFO] [stdout]   --> src/main.rs:66:9
[INFO] [stdout]    |
[INFO] [stdout] 66 |     let string = String::new();
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `string`
[INFO] [stdout]   --> src/main.rs:68:9
[INFO] [stdout]    |
[INFO] [stdout] 68 |     let string = String::from("string");
[INFO] [stdout]    |         ^^^^^^ help: if this is intentional, prefix it with an underscore: `_string`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `new_s`
[INFO] [stdout]   --> src/main.rs:84:9
[INFO] [stdout]    |
[INFO] [stdout] 84 |     let new_s = format!("{}-{}", new_s, s);
[INFO] [stdout]    |         ^^^^^ help: if this is intentional, prefix it with an underscore: `_new_s`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `k`
[INFO] [stdout]    --> src/main.rs:108:10
[INFO] [stdout]     |
[INFO] [stdout] 108 |     for (k, v) in map {}
[INFO] [stdout]     |          ^ help: if this is intentional, prefix it with an underscore: `_k`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused variable: `v`
[INFO] [stdout]    --> src/main.rs:108:13
[INFO] [stdout]     |
[INFO] [stdout] 108 |     for (k, v) in map {}
[INFO] [stdout]     |             ^ help: if this is intentional, prefix it with an underscore: `_v`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `vec` is never used
[INFO] [stdout]   --> src/main.rs:39:4
[INFO] [stdout]    |
[INFO] [stdout] 39 | fn vec() {
[INFO] [stdout]    |    ^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `str_and_string` is never used
[INFO] [stdout]   --> src/main.rs:62:4
[INFO] [stdout]    |
[INFO] [stdout] 62 | fn str_and_string() {
[INFO] [stdout]    |    ^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: function `hash_map` is never used
[INFO] [stdout]   --> src/main.rs:88:4
[INFO] [stdout]    |
[INFO] [stdout] 88 | fn hash_map() {
[INFO] [stdout]    |    ^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.09s
[INFO] running `Command { std: "docker" "inspect" "095e1196355ce8a1c855dbc60f5cfa17c19fb06fcd9eebbab664c5bc688dcf52", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "095e1196355ce8a1c855dbc60f5cfa17c19fb06fcd9eebbab664c5bc688dcf52", kill_on_drop: false }`
[INFO] [stdout] 095e1196355ce8a1c855dbc60f5cfa17c19fb06fcd9eebbab664c5bc688dcf52