[INFO] cloning repository https://github.com/kometen/mergesort
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/kometen/mergesort" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkometen%2Fmergesort", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkometen%2Fmergesort'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] bdad3d2b7068d5ac2d74888c6b6c752e5acd8e2e
[INFO] building kometen/mergesort against master#11663cd3bfefef7d34e8f0892c250bf698049392+rustflags=-Dtail-expr-drop-order for pr-134523
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fkometen%2Fmergesort" "/workspace/builds/worker-4-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/kometen/mergesort 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 git repo https://github.com/kometen/mergesort
[INFO] finished tweaking git repo https://github.com/kometen/mergesort
[INFO] tweaked toml for git repo https://github.com/kometen/mergesort written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/kometen/mergesort 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 894220f1d9d5287c903ec05f2db0468201d0f00d63ec871276cfce81c56d7b48
[INFO] running `Command { std: "docker" "start" "-a" "894220f1d9d5287c903ec05f2db0468201d0f00d63ec871276cfce81c56d7b48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "894220f1d9d5287c903ec05f2db0468201d0f00d63ec871276cfce81c56d7b48", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "894220f1d9d5287c903ec05f2db0468201d0f00d63ec871276cfce81c56d7b48", kill_on_drop: false }`
[INFO] [stdout] 894220f1d9d5287c903ec05f2db0468201d0f00d63ec871276cfce81c56d7b48
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 0d9b9138b9fde40dc5dc94ae31200f1c161c9be796dbe5b02ed23454332e5473
[INFO] running `Command { std: "docker" "start" "-a" "0d9b9138b9fde40dc5dc94ae31200f1c161c9be796dbe5b02ed23454332e5473", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.98
[INFO] [stderr]    Compiling bitflags v1.2.1
[INFO] [stderr]    Compiling unicode-width v0.1.8
[INFO] [stderr]    Compiling vec_map v0.8.2
[INFO] [stderr]    Compiling ansi_term v0.11.0
[INFO] [stderr]    Compiling strsim v0.8.0
[INFO] [stderr]    Compiling textwrap v0.11.0
[INFO] [stderr]    Compiling atty v0.2.14
[INFO] [stderr]    Compiling clap v2.33.3
[INFO] [stderr]    Compiling mergesort v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `max_size`
[INFO] [stdout]   --> src/main.rs:37:13
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut max_size = 1;
[INFO] [stdout]    |             ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_max_size`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` 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 max_size = 1;
[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:40:9
[INFO] [stdout]    |
[INFO] [stdout] 40 |     let mut width = 1;
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 4.62s
[INFO] running `Command { std: "docker" "inspect" "0d9b9138b9fde40dc5dc94ae31200f1c161c9be796dbe5b02ed23454332e5473", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0d9b9138b9fde40dc5dc94ae31200f1c161c9be796dbe5b02ed23454332e5473", kill_on_drop: false }`
[INFO] [stdout] 0d9b9138b9fde40dc5dc94ae31200f1c161c9be796dbe5b02ed23454332e5473
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 97d8acd222d7dbe66a9f3e0f8ecd6ad5720db27aad311b15c7f33589f9a5d518
[INFO] running `Command { std: "docker" "start" "-a" "97d8acd222d7dbe66a9f3e0f8ecd6ad5720db27aad311b15c7f33589f9a5d518", kill_on_drop: false }`
[INFO] [stderr]    Compiling mergesort v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused variable: `max_size`
[INFO] [stdout]   --> src/main.rs:37:13
[INFO] [stdout]    |
[INFO] [stdout] 37 |     let mut max_size = 1;
[INFO] [stdout]    |             ^^^^^^^^ help: if this is intentional, prefix it with an underscore: `_max_size`
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_variables)]` 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 max_size = 1;
[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:40:9
[INFO] [stdout]    |
[INFO] [stdout] 40 |     let mut width = 1;
[INFO] [stdout]    |         ----^^^^^
[INFO] [stdout]    |         |
[INFO] [stdout]    |         help: remove this `mut`
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.18s
[INFO] running `Command { std: "docker" "inspect" "97d8acd222d7dbe66a9f3e0f8ecd6ad5720db27aad311b15c7f33589f9a5d518", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "97d8acd222d7dbe66a9f3e0f8ecd6ad5720db27aad311b15c7f33589f9a5d518", kill_on_drop: false }`
[INFO] [stdout] 97d8acd222d7dbe66a9f3e0f8ecd6ad5720db27aad311b15c7f33589f9a5d518