[INFO] crate drone-async-await 0.9.0 is already in cache
[INFO] checking drone-async-await-0.9.0 against master#6250d56355d72264ece721e8d0dc95b16a6824b1 for pr-68350
[INFO] extracting crate drone-async-await 0.9.0 into /workspace/builds/worker-4/source
[INFO] validating manifest of crates.io crate drone-async-await 0.9.0 on toolchain 6250d56355d72264ece721e8d0dc95b16a6824b1
[INFO] running `"/workspace/cargo-home/bin/cargo" "+6250d56355d72264ece721e8d0dc95b16a6824b1" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started tweaking crates.io crate drone-async-await 0.9.0
[INFO] finished tweaking crates.io crate drone-async-await 0.9.0
[INFO] tweaked toml for crates.io crate drone-async-await 0.9.0 written to /workspace/builds/worker-4/source/Cargo.toml
[INFO] running `"/workspace/cargo-home/bin/cargo" "+6250d56355d72264ece721e8d0dc95b16a6824b1" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/workspace/cargo-home/bin/cargo" "+6250d56355d72264ece721e8d0dc95b16a6824b1" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[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" "+6250d56355d72264ece721e8d0dc95b16a6824b1" "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] ee60de2386d3c38eda28449e5c9263ae1e45f230308a3582be6994491d4ea05d
[INFO] running `"docker" "start" "-a" "ee60de2386d3c38eda28449e5c9263ae1e45f230308a3582be6994491d4ea05d"`
[INFO] [stderr]     Checking futures-core-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-sink-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-io-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking drone-ctypes v0.9.0
[INFO] [stderr]    Compiling syn v0.15.44
[INFO] [stderr]    Compiling serde v1.0.104
[INFO] [stderr]    Compiling failure v0.1.6
[INFO] [stderr]     Checking futures-util-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-channel-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-executor-preview v0.3.0-alpha.19
[INFO] [stderr]     Checking futures-preview v0.3.0-alpha.19
[INFO] [stderr]    Compiling drone-macros-core v0.9.0
[INFO] [stderr]    Compiling toml v0.4.10
[INFO] [stderr]    Compiling drone-config v0.9.0
[INFO] [stderr]    Compiling drone-core-macros v0.9.0
[INFO] [stderr]     Checking drone-core v0.9.0
[INFO] [stderr] error[E0740]: unions may not contain fields that need dropping
[INFO] [stderr]    --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/drone-core-0.9.0/src/stack_loop.rs:129:5
[INFO] [stderr]     |
[INFO] [stderr] 129 |     cmd: Cmd,
[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/drone-core-0.9.0/src/stack_loop.rs:129:5
[INFO] [stderr]     |
[INFO] [stderr] 129 |     cmd: Cmd,
[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 `drone-core`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "ee60de2386d3c38eda28449e5c9263ae1e45f230308a3582be6994491d4ea05d"`
[INFO] running `"docker" "rm" "-f" "ee60de2386d3c38eda28449e5c9263ae1e45f230308a3582be6994491d4ea05d"`
[INFO] [stdout] ee60de2386d3c38eda28449e5c9263ae1e45f230308a3582be6994491d4ea05d