[INFO] cloning repository https://github.com/amarao/rust_dual
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/amarao/rust_dual" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famarao%2Frust_dual", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famarao%2Frust_dual'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3ad4e382ebe99672f1b1b988e70f6152a7ba16f7
[INFO] checking amarao/rust_dual against try#45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4 for pr-83744
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Famarao%2Frust_dual" "/workspace/builds/worker-8/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-8/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/amarao/rust_dual on toolchain 45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/amarao/rust_dual
[INFO] finished tweaking git repo https://github.com/amarao/rust_dual
[INFO] tweaked toml for git repo https://github.com/amarao/rust_dual written to /workspace/builds/worker-8/source/Cargo.toml
[INFO] crate git repo https://github.com/amarao/rust_dual already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 92ba88a97d574e5cefd8293c2c31082e1554bbb9efe166f2cdbcec00da38c6f0
[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" "92ba88a97d574e5cefd8293c2c31082e1554bbb9efe166f2cdbcec00da38c6f0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "92ba88a97d574e5cefd8293c2c31082e1554bbb9efe166f2cdbcec00da38c6f0", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "92ba88a97d574e5cefd8293c2c31082e1554bbb9efe166f2cdbcec00da38c6f0", kill_on_drop: false }`
[INFO] [stdout] 92ba88a97d574e5cefd8293c2c31082e1554bbb9efe166f2cdbcec00da38c6f0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-8/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+45d8b6e68beee1c9c1ce92ae258a7e02f8f13aa4" "check" "--frozen" "--all" "--all-targets" "--message-format=json", 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] 20ecf1967fcde9f15f7696182b09474a123da2aff930ce0f2d54e3af2b996def
[INFO] running `Command { std: "docker" "start" "-a" "20ecf1967fcde9f15f7696182b09474a123da2aff930ce0f2d54e3af2b996def", kill_on_drop: false }`
[INFO] [stderr]     Checking dual v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 | fn loop_set(mut mw: Multiwrite) {
[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:103:9
[INFO] [stdout]     |
[INFO] [stdout] 103 |     let mut a = Multiwrite::new(1, 0).unwrap();
[INFO] [stdout]     |         ----^
[INFO] [stdout]     |         |
[INFO] [stdout]     |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: associated function is never used: `copy_into_slice`
[INFO] [stdout]   --> src/main.rs:34:8
[INFO] [stdout]    |
[INFO] [stdout] 34 |     fn copy_into_slice<T>(&self, dest: &mut [T]) -> Result<(), &'static str>
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: variable does not need to be mutable
[INFO] [stdout]   --> src/main.rs:75:13
[INFO] [stdout]    |
[INFO] [stdout] 75 | fn loop_set(mut mw: Multiwrite) {
[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: associated function is never used: `copy_into_slice`
[INFO] [stdout]   --> src/main.rs:34:8
[INFO] [stdout]    |
[INFO] [stdout] 34 |     fn copy_into_slice<T>(&self, dest: &mut [T]) -> Result<(), &'static str>
[INFO] [stdout]    |        ^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(dead_code)]` on by default
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 2 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 3 warnings emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished dev [unoptimized + debuginfo] target(s) in 0.33s
[INFO] running `Command { std: "docker" "inspect" "20ecf1967fcde9f15f7696182b09474a123da2aff930ce0f2d54e3af2b996def", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "20ecf1967fcde9f15f7696182b09474a123da2aff930ce0f2d54e3af2b996def", kill_on_drop: false }`
[INFO] [stdout] 20ecf1967fcde9f15f7696182b09474a123da2aff930ce0f2d54e3af2b996def