[INFO] cloning repository https://github.com/wiselucky/rustlings-answer
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/wiselucky/rustlings-answer" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwiselucky%2Frustlings-answer", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwiselucky%2Frustlings-answer'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] af3e5a376c0bdda0766c2ed8ad93e2f4e7034c8e
[INFO] checking wiselucky/rustlings-answer against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwiselucky%2Frustlings-answer" "/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/wiselucky/rustlings-answer 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/wiselucky/rustlings-answer
[INFO] finished tweaking git repo https://github.com/wiselucky/rustlings-answer
[INFO] tweaked toml for git repo https://github.com/wiselucky/rustlings-answer written to /workspace/builds/worker-4-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/wiselucky/rustlings-answer 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] 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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+385fa9d845dd326c6bbfd58c22244215e431948a" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 070867cde7c86c8c7b52c4272be2e1b26b692a983e99e3624a5b7d6f87044387
[INFO] running `Command { std: "docker" "start" "-a" "070867cde7c86c8c7b52c4272be2e1b26b692a983e99e3624a5b7d6f87044387", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "070867cde7c86c8c7b52c4272be2e1b26b692a983e99e3624a5b7d6f87044387", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "070867cde7c86c8c7b52c4272be2e1b26b692a983e99e3624a5b7d6f87044387", kill_on_drop: false }`
[INFO] [stdout] 070867cde7c86c8c7b52c4272be2e1b26b692a983e99e3624a5b7d6f87044387
[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" "-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] a34809a7fcfef4c9d7490ad1fe1989237b26436395c11990db2b5e56655c15b6
[INFO] running `Command { std: "docker" "start" "-a" "a34809a7fcfef4c9d7490ad1fe1989237b26436395c11990db2b5e56655c15b6", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.100
[INFO] [stderr]    Compiling proc-macro2 v1.0.28
[INFO] [stderr]    Compiling syn v1.0.75
[INFO] [stderr]    Compiling serde_derive v1.0.129
[INFO] [stderr]    Compiling serde v1.0.129
[INFO] [stderr]     Checking instant v0.1.10
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]     Checking smallvec v1.6.1
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking lock_api v0.4.4
[INFO] [stderr]     Checking slab v0.4.4
[INFO] [stderr]    Compiling serde_json v1.0.66
[INFO] [stderr]    Compiling unicode-segmentation v1.8.0
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]     Checking lazycell v1.3.0
[INFO] [stderr]    Compiling argh_shared v0.1.5
[INFO] [stderr]    Compiling escargot v0.4.0
[INFO] [stderr]     Checking predicates-core v1.0.2
[INFO] [stderr]     Checking itoa v0.4.8
[INFO] [stderr]     Checking walkdir v2.3.2
[INFO] [stderr]     Checking treeline v0.1.0
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking predicates-tree v1.0.3
[INFO] [stderr]     Checking glob v0.3.0
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking parking_lot_core v0.8.3
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking net2 v0.2.37
[INFO] [stderr]     Checking inotify-sys v0.1.5
[INFO] [stderr]     Checking terminal_size v0.1.17
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking termios v0.3.3
[INFO] [stderr]     Checking clicolors-control v1.0.1
[INFO] [stderr]     Checking filetime v0.2.15
[INFO] [stderr]     Checking console v0.14.1
[INFO] [stderr]     Checking parking_lot v0.11.1
[INFO] [stderr]     Checking inotify v0.7.1
[INFO] [stderr]     Checking console v0.7.7
[INFO] [stderr]     Checking mio v0.6.23
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking float-cmp v0.8.0
[INFO] [stderr]     Checking indicatif v0.10.3
[INFO] [stderr]     Checking predicates v1.0.8
[INFO] [stderr]     Checking mio-extras v2.0.6
[INFO] [stderr]     Checking notify v4.0.17
[INFO] [stderr]    Compiling argh_derive v0.1.5
[INFO] [stderr]     Checking argh v0.1.5
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]     Checking rustlings v4.6.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking assert_cmd v0.11.1
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 16.22s
[INFO] running `Command { std: "docker" "inspect" "a34809a7fcfef4c9d7490ad1fe1989237b26436395c11990db2b5e56655c15b6", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a34809a7fcfef4c9d7490ad1fe1989237b26436395c11990db2b5e56655c15b6", kill_on_drop: false }`
[INFO] [stdout] a34809a7fcfef4c9d7490ad1fe1989237b26436395c11990db2b5e56655c15b6
[INFO] checking wiselucky/rustlings-answer against try#645bb72776a6a56a1a8f52631a44bd082b2ba509 for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fwiselucky%2Frustlings-answer" "/workspace/builds/worker-4-tc2/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-4-tc2/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/wiselucky/rustlings-answer 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/wiselucky/rustlings-answer
[INFO] finished tweaking git repo https://github.com/wiselucky/rustlings-answer
[INFO] tweaked toml for git repo https://github.com/wiselucky/rustlings-answer written to /workspace/builds/worker-4-tc2/source/Cargo.toml
[INFO] crate git repo https://github.com/wiselucky/rustlings-answer 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-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] be5089f681498956a2634e996ba4f4d98d4e6c27649153c0288a492a1aac2e25
[INFO] running `Command { std: "docker" "start" "-a" "be5089f681498956a2634e996ba4f4d98d4e6c27649153c0288a492a1aac2e25", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "be5089f681498956a2634e996ba4f4d98d4e6c27649153c0288a492a1aac2e25", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "be5089f681498956a2634e996ba4f4d98d4e6c27649153c0288a492a1aac2e25", kill_on_drop: false }`
[INFO] [stdout] be5089f681498956a2634e996ba4f4d98d4e6c27649153c0288a492a1aac2e25
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-tc2/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4-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] 8b694a370315a13fee4823e7075d91c52bbd575892b8aadcee12f6ce4eb1bbc5
[INFO] running `Command { std: "docker" "start" "-a" "8b694a370315a13fee4823e7075d91c52bbd575892b8aadcee12f6ce4eb1bbc5", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.100
[INFO] [stderr]    Compiling proc-macro2 v1.0.28
[INFO] [stderr]    Compiling syn v1.0.75
[INFO] [stderr]    Compiling serde_derive v1.0.129
[INFO] [stderr]    Compiling serde v1.0.129
[INFO] [stderr]     Checking smallvec v1.6.1
[INFO] [stderr]    Compiling ryu v1.0.5
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling log v0.4.14
[INFO] [stderr]     Checking instant v0.1.10
[INFO] [stderr]     Checking lock_api v0.4.4
[INFO] [stderr]     Checking slab v0.4.4
[INFO] [stderr]     Checking unicode-width v0.1.8
[INFO] [stderr]    Compiling serde_json v1.0.66
[INFO] [stderr]    Compiling unicode-segmentation v1.8.0
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]    Compiling argh_shared v0.1.5
[INFO] [stderr]     Checking itoa v0.4.8
[INFO] [stderr]     Checking lazycell v1.3.0
[INFO] [stderr]     Checking predicates-core v1.0.2
[INFO] [stderr]    Compiling escargot v0.4.0
[INFO] [stderr]     Checking walkdir v2.3.2
[INFO] [stderr]     Checking difference v2.0.0
[INFO] [stderr]     Checking normalize-line-endings v0.3.0
[INFO] [stderr]     Checking treeline v0.1.0
[INFO] [stderr]     Checking glob v0.3.0
[INFO] [stderr]     Checking predicates-tree v1.0.3
[INFO] [stderr]    Compiling heck v0.3.3
[INFO] [stderr]    Compiling quote v1.0.9
[INFO] [stderr]     Checking parking_lot_core v0.8.3
[INFO] [stderr]     Checking net2 v0.2.37
[INFO] [stderr]     Checking iovec v0.1.4
[INFO] [stderr]     Checking terminal_size v0.1.17
[INFO] [stderr]     Checking inotify-sys v0.1.5
[INFO] [stderr]     Checking termios v0.3.3
[INFO] [stderr]     Checking clicolors-control v1.0.1
[INFO] [stderr]     Checking filetime v0.2.15
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking inotify v0.7.1
[INFO] [stderr]     Checking mio v0.6.23
[INFO] [stderr]     Checking parking_lot v0.11.1
[INFO] [stderr]     Checking console v0.14.1
[INFO] [stderr]     Checking float-cmp v0.8.0
[INFO] [stderr]     Checking number_prefix v0.2.8
[INFO] [stderr]     Checking predicates v1.0.8
[INFO] [stderr]     Checking console v0.7.7
[INFO] [stderr]     Checking indicatif v0.10.3
[INFO] [stderr]     Checking mio-extras v2.0.6
[INFO] [stderr]     Checking notify v4.0.17
[INFO] [stderr]    Compiling argh_derive v0.1.5
[INFO] [stderr]     Checking argh v0.1.5
[INFO] [stderr]     Checking toml v0.4.10
[INFO] [stderr]     Checking rustlings v4.6.0 (/opt/rustwide/workdir)
[INFO] [stderr]     Checking assert_cmd v0.11.1
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 17.23s
[INFO] running `Command { std: "docker" "inspect" "8b694a370315a13fee4823e7075d91c52bbd575892b8aadcee12f6ce4eb1bbc5", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8b694a370315a13fee4823e7075d91c52bbd575892b8aadcee12f6ce4eb1bbc5", kill_on_drop: false }`
[INFO] [stdout] 8b694a370315a13fee4823e7075d91c52bbd575892b8aadcee12f6ce4eb1bbc5