[INFO] cloning repository https://github.com/MichaelGrigoryan25/rust-xo
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/MichaelGrigoryan25/rust-xo" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMichaelGrigoryan25%2Frust-xo", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FMichaelGrigoryan25%2Frust-xo'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 1a640246e1428882e3fa1a4d35d69e85effca92c
[INFO] building MichaelGrigoryan25/rust-xo 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%2FMichaelGrigoryan25%2Frust-xo" "/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/MichaelGrigoryan25/rust-xo 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/MichaelGrigoryan25/rust-xo
[INFO] finished tweaking git repo https://github.com/MichaelGrigoryan25/rust-xo
[INFO] tweaked toml for git repo https://github.com/MichaelGrigoryan25/rust-xo written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/MichaelGrigoryan25/rust-xo 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] afa4fc924474a09159b25fd84cafeaa2eab157bccab21394ac4e113de408141e
[INFO] running `Command { std: "docker" "start" "-a" "afa4fc924474a09159b25fd84cafeaa2eab157bccab21394ac4e113de408141e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "afa4fc924474a09159b25fd84cafeaa2eab157bccab21394ac4e113de408141e", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "afa4fc924474a09159b25fd84cafeaa2eab157bccab21394ac4e113de408141e", kill_on_drop: false }`
[INFO] [stdout] afa4fc924474a09159b25fd84cafeaa2eab157bccab21394ac4e113de408141e
[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] ba0ebfb9411c9e942649048a1deaeb8d2e18c0d9ac98a426bd74c2fec482b2fc
[INFO] running `Command { std: "docker" "start" "-a" "ba0ebfb9411c9e942649048a1deaeb8d2e18c0d9ac98a426bd74c2fec482b2fc", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.94
[INFO] [stderr]    Compiling getrandom v0.2.2
[INFO] [stderr]    Compiling ppv-lite86 v0.2.10
[INFO] [stderr]    Compiling ansi_term v0.12.1
[INFO] [stderr]    Compiling rand_core v0.6.2
[INFO] [stderr]    Compiling rand_chacha v0.3.0
[INFO] [stderr]    Compiling rand v0.8.3
[INFO] [stderr]    Compiling rust-xo v1.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 30 |         let _ = &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:52:9
[INFO] [stdout]    |
[INFO] [stdout] 52 |         &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 52 |         let _ = &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:26:13
[INFO] [stdout]    |
[INFO] [stdout] 26 |             &position_string.clear();
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 26 |             let _ = &position_string.clear();
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:40:17
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 &position_string.clear();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 let _ = &position_string.clear();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 1.93s
[INFO] running `Command { std: "docker" "inspect" "ba0ebfb9411c9e942649048a1deaeb8d2e18c0d9ac98a426bd74c2fec482b2fc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ba0ebfb9411c9e942649048a1deaeb8d2e18c0d9ac98a426bd74c2fec482b2fc", kill_on_drop: false }`
[INFO] [stdout] ba0ebfb9411c9e942649048a1deaeb8d2e18c0d9ac98a426bd74c2fec482b2fc
[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] 64b7eaa0a5e27dedcf4bf03d41fcf2dd1dff3da4d3bff55790bba65da36b5627
[INFO] running `Command { std: "docker" "start" "-a" "64b7eaa0a5e27dedcf4bf03d41fcf2dd1dff3da4d3bff55790bba65da36b5627", kill_on_drop: false }`
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 30 |         let _ = &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:52:9
[INFO] [stdout]    |
[INFO] [stdout] 52 |         &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 52 |         let _ = &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:26:13
[INFO] [stdout]    |
[INFO] [stdout] 26 |             &position_string.clear();
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 26 |             let _ = &position_string.clear();
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]    Compiling rust-xo v1.2.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:40:17
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 &position_string.clear();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 let _ = &position_string.clear();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:30:9
[INFO] [stdout]    |
[INFO] [stdout] 30 |         &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 30 |         let _ = &board_string.push_str(&format!("{}\n", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/board.rs:52:9
[INFO] [stdout]    |
[INFO] [stdout] 52 |         &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 52 |         let _ = &board_string.push_str(&format!("{}", &divider));
[INFO] [stdout]    |         +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:26:13
[INFO] [stdout]    |
[INFO] [stdout] 26 |             &position_string.clear();
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 26 |             let _ = &position_string.clear();
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused borrow that must be used
[INFO] [stdout]   --> src/moves.rs:40:17
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 &position_string.clear();
[INFO] [stdout]    |                 ^^^^^^^^^^^^^^^^^^^^^^^^ the borrow produces a value
[INFO] [stdout]    |
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 40 |                 let _ = &position_string.clear();
[INFO] [stdout]    |                 +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `test` profile [unoptimized + debuginfo] target(s) in 0.14s
[INFO] running `Command { std: "docker" "inspect" "64b7eaa0a5e27dedcf4bf03d41fcf2dd1dff3da4d3bff55790bba65da36b5627", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "64b7eaa0a5e27dedcf4bf03d41fcf2dd1dff3da4d3bff55790bba65da36b5627", kill_on_drop: false }`
[INFO] [stdout] 64b7eaa0a5e27dedcf4bf03d41fcf2dd1dff3da4d3bff55790bba65da36b5627