[INFO] fetching crate atsamd21-hal 0.3.1...
[INFO] checking atsamd21-hal-0.3.1 against master#36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923 for pr-81863
[INFO] extracting crate atsamd21-hal 0.3.1 into /workspace/builds/worker-5/source
[INFO] validating manifest of crates.io crate atsamd21-hal 0.3.1 on toolchain 36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate atsamd21-hal 0.3.1
[INFO] finished tweaking crates.io crate atsamd21-hal 0.3.1
[INFO] tweaked toml for crates.io crate atsamd21-hal 0.3.1 written to /workspace/builds/worker-5/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 79675c5f9bd620b3e2f9d7d6566f7e6fc6b8131a8d7a66fff0520dce1f79fafd
[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" "79675c5f9bd620b3e2f9d7d6566f7e6fc6b8131a8d7a66fff0520dce1f79fafd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "79675c5f9bd620b3e2f9d7d6566f7e6fc6b8131a8d7a66fff0520dce1f79fafd", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "79675c5f9bd620b3e2f9d7d6566f7e6fc6b8131a8d7a66fff0520dce1f79fafd", kill_on_drop: false }`
[INFO] [stdout] 79675c5f9bd620b3e2f9d7d6566f7e6fc6b8131a8d7a66fff0520dce1f79fafd
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-5/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" "rustops/crates-build-env@sha256:21f1ed92105a0ef9b0d27ad8bdeb7f36f9f01ac17fffe3a3f3dc5241fc25d8f4" "/opt/rustwide/cargo-home/bin/cargo" "+36ecbc94eb6be90bc38b2d0fdd4bfac3f34d9923" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] a0a1d0e82c0861d7602311425b0e3772482fdb4310a3095e1193622589ed6f0b
[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" "a0a1d0e82c0861d7602311425b0e3772482fdb4310a3095e1193622589ed6f0b", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.24
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling syn v1.0.60
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]    Compiling libc v0.2.85
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling adler v0.2.3
[INFO] [stderr]    Compiling gimli v0.23.0
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling object v0.23.0
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]    Compiling rustc-demangle v0.1.18
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling cortex-m v0.5.11
[INFO] [stderr]    Compiling cc v1.0.66
[INFO] [stderr]    Compiling cortex-m-semihosting v0.3.7
[INFO] [stderr]    Compiling cortex-m v0.4.3
[INFO] [stderr]     Checking aligned v0.2.0
[INFO] [stderr]     Checking untagged-option v0.1.1
[INFO] [stderr]     Checking aligned v0.1.2
[INFO] [stdout] error[E0740]: unions may not contain fields that need dropping
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/untagged-option-0.1.1/src/lib.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     pub some: T,
[INFO] [stdout]    |     ^^^^^^^^^^^
[INFO] [stdout]    |
[INFO] [stdout] note: `std::mem::ManuallyDrop` can be used to wrap the type
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/untagged-option-0.1.1/src/lib.rs:53:5
[INFO] [stdout]    |
[INFO] [stdout] 53 |     pub some: T,
[INFO] [stdout]    |     ^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stderr]     Checking bare-metal v0.1.3
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0740`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `untagged-option`
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "a0a1d0e82c0861d7602311425b0e3772482fdb4310a3095e1193622589ed6f0b", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a0a1d0e82c0861d7602311425b0e3772482fdb4310a3095e1193622589ed6f0b", kill_on_drop: false }`
[INFO] [stdout] a0a1d0e82c0861d7602311425b0e3772482fdb4310a3095e1193622589ed6f0b