[INFO] cloning repository https://github.com/AJTJ/rust_problems
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/AJTJ/rust_problems" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAJTJ%2Frust_problems", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAJTJ%2Frust_problems'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] 87f258cdf9eab9b23a01bba18486cecee34b3f8b
[INFO] checking AJTJ/rust_problems against try#3bb2879ea9e58d65b875f9a98df44f4a43ce2597 for pr-85387
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2FAJTJ%2Frust_problems" "/workspace/builds/worker-10/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-10/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/AJTJ/rust_problems on toolchain 3bb2879ea9e58d65b875f9a98df44f4a43ce2597
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3bb2879ea9e58d65b875f9a98df44f4a43ce2597" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/AJTJ/rust_problems
[INFO] finished tweaking git repo https://github.com/AJTJ/rust_problems
[INFO] tweaked toml for git repo https://github.com/AJTJ/rust_problems written to /workspace/builds/worker-10/source/Cargo.toml
[INFO] crate git repo https://github.com/AJTJ/rust_problems already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+3bb2879ea9e58d65b875f9a98df44f4a43ce2597" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+3bb2879ea9e58d65b875f9a98df44f4a43ce2597" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 06a258cb75160a06d63b86928fa52cae3163866ea62e64b7c4ea0a20edb5da86
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "06a258cb75160a06d63b86928fa52cae3163866ea62e64b7c4ea0a20edb5da86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "06a258cb75160a06d63b86928fa52cae3163866ea62e64b7c4ea0a20edb5da86", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "06a258cb75160a06d63b86928fa52cae3163866ea62e64b7c4ea0a20edb5da86", kill_on_drop: false }`
[INFO] [stdout] 06a258cb75160a06d63b86928fa52cae3163866ea62e64b7c4ea0a20edb5da86
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-10/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" "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@sha256:20528e8c29e4536546f0102ce88568b16ea7538393a33fcca951030f7af10457" "/opt/rustwide/cargo-home/bin/cargo" "+3bb2879ea9e58d65b875f9a98df44f4a43ce2597" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ba08416fb01ff499e5144f6dfde2092c6bdbfc6b7efb665dbe373b05c9b3be5f
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "ba08416fb01ff499e5144f6dfde2092c6bdbfc6b7efb665dbe373b05c9b3be5f", kill_on_drop: false }`
[INFO] [stderr] Checking rust_problems v0.1.0 (/opt/rustwide/workdir)
[INFO] [stdout] error[E0277]: cannot add `Option