[INFO] cloning repository https://github.com/Al-khali/learning_rust
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/Al-khali/learning_rust" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAl-khali%2Flearning_rust", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAl-khali%2Flearning_rust'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 2d8b5fe6aea0a6e14bb88bbb1b5204c1911be31d
[INFO] checking Al-khali/learning_rust/2d8b5fe6aea0a6e14bb88bbb1b5204c1911be31d against try#7014e13d5becc920d4bea3cd87942c8a13d359bf+rustflags=-Dtail_expr_drop_order for pr-129864
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAl-khali%2Flearning_rust" "/workspace/builds/worker-6-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-6-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/Al-khali/learning_rust on toolchain 7014e13d5becc920d4bea3cd87942c8a13d359bf
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/Al-khali/learning_rust
[INFO] finished tweaking git repo https://github.com/Al-khali/learning_rust
[INFO] tweaked toml for git repo https://github.com/Al-khali/learning_rust written to /workspace/builds/worker-6-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/Al-khali/learning_rust 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" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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:ceb6ea022f8a89cebbe621bb4987e73a935bd40dfbb726f832cfff4742a5b95a" "/opt/rustwide/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 07c08ae354b0643aa3ef117e939d1a7973b4a6173c288d6a1a7d9ba62a9a47ee
[INFO] running `Command { std: "docker" "start" "-a" "07c08ae354b0643aa3ef117e939d1a7973b4a6173c288d6a1a7d9ba62a9a47ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "07c08ae354b0643aa3ef117e939d1a7973b4a6173c288d6a1a7d9ba62a9a47ee", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "07c08ae354b0643aa3ef117e939d1a7973b4a6173c288d6a1a7d9ba62a9a47ee", kill_on_drop: false }`
[INFO] [stdout] 07c08ae354b0643aa3ef117e939d1a7973b4a6173c288d6a1a7d9ba62a9a47ee
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-6-tc2/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:ceb6ea022f8a89cebbe621bb4987e73a935bd40dfbb726f832cfff4742a5b95a" "/opt/rustwide/cargo-home/bin/cargo" "+7014e13d5becc920d4bea3cd87942c8a13d359bf" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] f3ecdd6846bb8c64c34f5349833325879b141aba005d27b2eddc1582998f8b84
[INFO] running `Command { std: "docker" "start" "-a" "f3ecdd6846bb8c64c34f5349833325879b141aba005d27b2eddc1582998f8b84", kill_on_drop: false }`
[INFO] [stderr]     Checking premier_pas v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: unused return value of `Option::<T>::insert` that must be used
[INFO] [stdout]   --> src/main.rs:72:13
[INFO] [stdout]    |
[INFO] [stdout] 72 |             current_node.insert(new_node);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you intended to set a value, consider assignment instead
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 72 |             let _ = current_node.insert(new_node);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: unused return value of `Option::<T>::insert` that must be used
[INFO] [stdout]   --> src/main.rs:72:13
[INFO] [stdout]    |
[INFO] [stdout] 72 |             current_node.insert(new_node);
[INFO] [stdout]    |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout]    = note: if you intended to set a value, consider assignment instead
[INFO] [stdout]    = note: `#[warn(unused_must_use)]` on by default
[INFO] [stdout] help: use `let _ = ...` to ignore the resulting value
[INFO] [stdout]    |
[INFO] [stdout] 72 |             let _ = current_node.insert(new_node);
[INFO] [stdout]    |             +++++++
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: 1 warning emitted
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.28s
[INFO] running `Command { std: "docker" "inspect" "f3ecdd6846bb8c64c34f5349833325879b141aba005d27b2eddc1582998f8b84", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "f3ecdd6846bb8c64c34f5349833325879b141aba005d27b2eddc1582998f8b84", kill_on_drop: false }`
[INFO] [stdout] f3ecdd6846bb8c64c34f5349833325879b141aba005d27b2eddc1582998f8b84