[INFO] cloning repository https://github.com/binocvlar/Rustlang-Towers-of-Hanoi
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/binocvlar/Rustlang-Towers-of-Hanoi" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbinocvlar%2FRustlang-Towers-of-Hanoi", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbinocvlar%2FRustlang-Towers-of-Hanoi'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] f7b1c678e71abb6688bd69260ffcbf56a6d5aeba
[INFO] checking binocvlar/Rustlang-Towers-of-Hanoi against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbinocvlar%2FRustlang-Towers-of-Hanoi" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi on toolchain 385fa9d845dd326c6bbfd58c22244215e431948a
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi
[INFO] finished tweaking git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi
[INFO] tweaked toml for git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi 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" "+385fa9d845dd326c6bbfd58c22244215e431948a" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded nix v0.24.2
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0a4f0368e9103595b005980926fdff6992ec67e95717e1bd58bcdfebb5a730ea
[INFO] running `Command { std: "docker" "start" "-a" "0a4f0368e9103595b005980926fdff6992ec67e95717e1bd58bcdfebb5a730ea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0a4f0368e9103595b005980926fdff6992ec67e95717e1bd58bcdfebb5a730ea", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0a4f0368e9103595b005980926fdff6992ec67e95717e1bd58bcdfebb5a730ea", kill_on_drop: false }`
[INFO] [stdout] 0a4f0368e9103595b005980926fdff6992ec67e95717e1bd58bcdfebb5a730ea
[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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 32fd68903c2935349be4a765da5b5d9552b8f8ba9cf7e02c01f35dd857475657
[INFO] running `Command { std: "docker" "start" "-a" "32fd68903c2935349be4a765da5b5d9552b8f8ba9cf7e02c01f35dd857475657", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]     Checking numtoa v0.1.0
[INFO] [stderr]     Checking argparse v0.2.2
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking nix v0.24.2
[INFO] [stderr]     Checking termion v1.5.6
[INFO] [stderr]     Checking ctrlc v3.2.2
[INFO] [stderr]     Checking towers_of_hanoi v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.24s
[INFO] running `Command { std: "docker" "inspect" "32fd68903c2935349be4a765da5b5d9552b8f8ba9cf7e02c01f35dd857475657", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "32fd68903c2935349be4a765da5b5d9552b8f8ba9cf7e02c01f35dd857475657", kill_on_drop: false }`
[INFO] [stdout] 32fd68903c2935349be4a765da5b5d9552b8f8ba9cf7e02c01f35dd857475657
[INFO] checking binocvlar/Rustlang-Towers-of-Hanoi against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fbinocvlar%2FRustlang-Towers-of-Hanoi" "/workspace/builds/worker-7-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi on toolchain 645bb72776a6a56a1a8f52631a44bd082b2ba509
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi
[INFO] finished tweaking git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi
[INFO] tweaked toml for git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi written to /workspace/builds/worker-7-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/binocvlar/Rustlang-Towers-of-Hanoi 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" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 0c6e92db5ed5858cd633d2c69586301139d79ba5c5eabdce74b24bfcf98e3726
[INFO] running `Command { std: "docker" "start" "-a" "0c6e92db5ed5858cd633d2c69586301139d79ba5c5eabdce74b24bfcf98e3726", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "0c6e92db5ed5858cd633d2c69586301139d79ba5c5eabdce74b24bfcf98e3726", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "0c6e92db5ed5858cd633d2c69586301139d79ba5c5eabdce74b24bfcf98e3726", kill_on_drop: false }`
[INFO] [stdout] 0c6e92db5ed5858cd633d2c69586301139d79ba5c5eabdce74b24bfcf98e3726
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-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" "-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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+645bb72776a6a56a1a8f52631a44bd082b2ba509" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 248c417a30579f0883521f5502d24f048fb5cfeedfb06156ca1cfe6cb34775dc
[INFO] running `Command { std: "docker" "start" "-a" "248c417a30579f0883521f5502d24f048fb5cfeedfb06156ca1cfe6cb34775dc", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.126
[INFO] [stderr]     Checking numtoa v0.1.0
[INFO] [stderr]     Checking argparse v0.2.2
[INFO] [stderr]     Checking itertools v0.7.11
[INFO] [stderr]     Checking nix v0.24.2
[INFO] [stderr]     Checking termion v1.5.6
[INFO] [stderr]     Checking ctrlc v3.2.2
[INFO] [stderr]     Checking towers_of_hanoi v0.1.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 2.50s
[INFO] running `Command { std: "docker" "inspect" "248c417a30579f0883521f5502d24f048fb5cfeedfb06156ca1cfe6cb34775dc", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "248c417a30579f0883521f5502d24f048fb5cfeedfb06156ca1cfe6cb34775dc", kill_on_drop: false }`
[INFO] [stdout] 248c417a30579f0883521f5502d24f048fb5cfeedfb06156ca1cfe6cb34775dc