[INFO] cloning repository https://github.com/jkachmar/rust-in-action
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/jkachmar/rust-in-action" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjkachmar%2Frust-in-action", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjkachmar%2Frust-in-action'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 3f3aa2693352c5248c4c6418d2658ba2ec69c115
[INFO] checking jkachmar/rust-in-action against master#385fa9d845dd326c6bbfd58c22244215e431948a for absurd-question-mark-desugar
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fjkachmar%2Frust-in-action" "/workspace/builds/worker-1-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/jkachmar/rust-in-action 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/jkachmar/rust-in-action
[INFO] finished tweaking git repo https://github.com/jkachmar/rust-in-action
[INFO] tweaked toml for git repo https://github.com/jkachmar/rust-in-action written to /workspace/builds/worker-1-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/jkachmar/rust-in-action 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-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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] 3ac025f637040a3e65bb2c3aa839c62c2ad71cd5544445a199942be708355199
[INFO] running `Command { std: "docker" "start" "-a" "3ac025f637040a3e65bb2c3aa839c62c2ad71cd5544445a199942be708355199", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "3ac025f637040a3e65bb2c3aa839c62c2ad71cd5544445a199942be708355199", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "3ac025f637040a3e65bb2c3aa839c62c2ad71cd5544445a199942be708355199", kill_on_drop: false }`
[INFO] [stdout] 3ac025f637040a3e65bb2c3aa839c62c2ad71cd5544445a199942be708355199
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1-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] 07b02386975df0cd18a0413b917f4a2d724a08e1194226c857102c2fcfa74833
[INFO] running `Command { std: "docker" "start" "-a" "07b02386975df0cd18a0413b917f4a2d724a08e1194226c857102c2fcfa74833", kill_on_drop: false }`
[INFO] [stderr]    Compiling num-traits v0.2.14
[INFO] [stderr]    Compiling num-integer v0.1.44
[INFO] [stderr]    Compiling num-bigint v0.4.2
[INFO] [stderr]    Compiling memchr v2.4.1
[INFO] [stderr]    Compiling libc v0.2.103
[INFO] [stderr]    Compiling num-rational v0.4.0
[INFO] [stderr]    Compiling num-iter v0.1.42
[INFO] [stderr]     Checking unicode-width v0.1.9
[INFO] [stderr]     Checking ansi_term v0.11.0
[INFO] [stderr]     Checking strsim v0.8.0
[INFO] [stderr]     Checking bitflags v1.3.2
[INFO] [stderr]     Checking vec_map v0.8.2
[INFO] [stderr]     Checking textwrap v0.11.0
[INFO] [stderr]     Checking aho-corasick v0.7.18
[INFO] [stderr]     Checking atty v0.2.14
[INFO] [stderr]     Checking clap v2.33.3
[INFO] [stderr]     Checking num-complex v0.4.0
[INFO] [stderr]     Checking regex v1.5.4
[INFO] [stderr]     Checking num v0.4.0
[INFO] [stderr]     Checking chapter_2 v0.0.0 (/opt/rustwide/workdir/chapter_2)
[INFO] [stderr]     Finished `dev` profile [unoptimized + debuginfo] target(s) in 3.52s
[INFO] running `Command { std: "docker" "inspect" "07b02386975df0cd18a0413b917f4a2d724a08e1194226c857102c2fcfa74833", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "07b02386975df0cd18a0413b917f4a2d724a08e1194226c857102c2fcfa74833", kill_on_drop: false }`
[INFO] [stdout] 07b02386975df0cd18a0413b917f4a2d724a08e1194226c857102c2fcfa74833