[INFO] cloning repository https://github.com/cod1r/math_expression
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/cod1r/math_expression" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcod1r%2Fmath_expression", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcod1r%2Fmath_expression'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 635dee2c7fc57b3b7d1dddfe7bc7d21cb56c1712
[INFO] checking cod1r/math_expression against master#cccf075eba88363269e8589ebb8d40874cc542d8 for pr-142681
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fcod1r%2Fmath_expression" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] started tweaking git repo https://github.com/cod1r/math_expression
[INFO] finished tweaking git repo https://github.com/cod1r/math_expression
[INFO] tweaked toml for git repo https://github.com/cod1r/math_expression written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] validating manifest of git repo https://github.com/cod1r/math_expression on toolchain cccf075eba88363269e8589ebb8d40874cc542d8
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+cccf075eba88363269e8589ebb8d40874cc542d8" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate git repo https://github.com/cod1r/math_expression 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" "+cccf075eba88363269e8589ebb8d40874cc542d8" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Blocking waiting for file lock on package cache
[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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+cccf075eba88363269e8589ebb8d40874cc542d8" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c84d4527feefb3d551bf548c8455e74fb1fcafda25f75c4fa9a082caa239a6d8
[INFO] running `Command { std: "docker" "start" "-a" "c84d4527feefb3d551bf548c8455e74fb1fcafda25f75c4fa9a082caa239a6d8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c84d4527feefb3d551bf548c8455e74fb1fcafda25f75c4fa9a082caa239a6d8", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c84d4527feefb3d551bf548c8455e74fb1fcafda25f75c4fa9a082caa239a6d8", kill_on_drop: false }`
[INFO] [stdout] c84d4527feefb3d551bf548c8455e74fb1fcafda25f75c4fa9a082caa239a6d8
[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" "-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:cf8efcab8866f2cf4285301c7418e2f4f2a9b088c91ba69c40d5b659f81557f7" "/opt/rustwide/cargo-home/bin/cargo" "+cccf075eba88363269e8589ebb8d40874cc542d8" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a9346713c0a4488b2b369459611c3a5db7a70edd9cefcb03f7d24a5b72161454
[INFO] running `Command { std: "docker" "start" "-a" "a9346713c0a4488b2b369459611c3a5db7a70edd9cefcb03f7d24a5b72161454", kill_on_drop: false }`
[INFO] [stderr]     Checking math_expression v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] warning: use of a double negation
[INFO] [stdout]    --> src/main.rs:669:51
[INFO] [stdout]     |
[INFO] [stdout] 669 |         assert!(traverse_expr_tree(&expr)? == 1 * --1);
[INFO] [stdout]     |                                                   ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: the prefix `--` could be misinterpreted as a decrement operator which exists in other languages
[INFO] [stdout]     = note: use `-= 1` if you meant to decrement the value
[INFO] [stdout]     = note: `#[warn(double_negations)]` on by default
[INFO] [stdout] help: add parentheses for clarity
[INFO] [stdout]     |
[INFO] [stdout] 669 |         assert!(traverse_expr_tree(&expr)? == 1 * -(-1));
[INFO] [stdout]     |                                                    +  +
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] warning: use of a double negation
[INFO] [stdout]    --> src/main.rs:685:54
[INFO] [stdout]     |
[INFO] [stdout] 685 |         assert!(traverse_expr_tree(&expr)? == 1 * -----1);
[INFO] [stdout]     |                                                      ^^^
[INFO] [stdout]     |
[INFO] [stdout]     = note: the prefix `--` could be misinterpreted as a decrement operator which exists in other languages
[INFO] [stdout]     = note: use `-= 1` if you meant to decrement the value
[INFO] [stdout] help: add parentheses for clarity
[INFO] [stdout]     |
[INFO] [stdout] 685 |         assert!(traverse_expr_tree(&expr)? == 1 * ----(-1));
[INFO] [stdout]     |                                                       +  +
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 0.22s
[INFO] running `Command { std: "docker" "inspect" "a9346713c0a4488b2b369459611c3a5db7a70edd9cefcb03f7d24a5b72161454", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a9346713c0a4488b2b369459611c3a5db7a70edd9cefcb03f7d24a5b72161454", kill_on_drop: false }`
[INFO] [stdout] a9346713c0a4488b2b369459611c3a5db7a70edd9cefcb03f7d24a5b72161454