[INFO] crate atsamd-hal 0.7.4 is already in cache
[INFO] checking atsamd-hal-0.7.4 against master#30ca215b4e38b32aa7abdd635c5e2d56f5724494 for pr-66037
[INFO] extracting crate atsamd-hal 0.7.4 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate atsamd-hal 0.7.4 on toolchain 30ca215b4e38b32aa7abdd635c5e2d56f5724494
[INFO] running `"/workspace/cargo-home/bin/cargo" "+30ca215b4e38b32aa7abdd635c5e2d56f5724494" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate atsamd-hal 0.7.4
[INFO] finished tweaking crates.io crate atsamd-hal 0.7.4
[INFO] tweaked toml for crates.io crate atsamd-hal 0.7.4 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+30ca215b4e38b32aa7abdd635c5e2d56f5724494" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+30ca215b4e38b32aa7abdd635c5e2d56f5724494" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `"docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-4/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" "MAP_USER_ID=0" "-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" "--network" "none" "rustops/crates-build-env" "/opt/rustwide/cargo-home/bin/cargo" "+30ca215b4e38b32aa7abdd635c5e2d56f5724494" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] ed160583fa9626465a13bd167c4ed6bc06d8edc90dc6e4d98954d0aefc2aaf9c
[INFO] running `"docker" "start" "-a" "ed160583fa9626465a13bd167c4ed6bc06d8edc90dc6e4d98954d0aefc2aaf9c"`
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling cortex-m v0.5.10
[INFO] [stderr]    Compiling cortex-m v0.4.3
[INFO] [stderr]    Compiling cortex-m-semihosting v0.3.5
[INFO] [stderr]    Compiling cortex-m-rtfm v0.3.4
[INFO] [stderr]     Checking void v1.0.2
[INFO] [stderr]     Checking aligned v0.1.2
[INFO] [stderr]     Checking aligned v0.2.0
[INFO] [stderr]     Checking bare-metal v0.1.3
[INFO] [stderr]     Checking nb v0.1.2
[INFO] [stderr]     Checking untagged-option v0.1.1
[INFO] [stderr]     Checking bitfield v0.13.2
[INFO] [stderr]     Checking rtfm-core v0.2.0
[INFO] [stderr]     Checking jlink_rtt v0.1.0
[INFO] [stderr]     Checking rand_core v0.5.1
[INFO] [stderr] error[E0740]: unions may not contain fields that need dropping
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/untagged-option-0.1.1/src/lib.rs:53:5
[INFO] [stderr]    |
[INFO] [stderr] 53 |     pub some: T,
[INFO] [stderr]    |     ^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr] note: `std::mem::ManuallyDrop` can be used to wrap the type
[INFO] [stderr]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/untagged-option-0.1.1/src/lib.rs:53:5
[INFO] [stderr]    |
[INFO] [stderr] 53 |     pub some: T,
[INFO] [stderr]    |     ^^^^^^^^^^^
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0740`.
[INFO] [stderr] error: could not compile `untagged-option`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "ed160583fa9626465a13bd167c4ed6bc06d8edc90dc6e4d98954d0aefc2aaf9c"`
[INFO] running `"docker" "rm" "-f" "ed160583fa9626465a13bd167c4ed6bc06d8edc90dc6e4d98954d0aefc2aaf9c"`
[INFO] [stdout] ed160583fa9626465a13bd167c4ed6bc06d8edc90dc6e4d98954d0aefc2aaf9c