[INFO] fetching crate keymatrix 0.1.2...
[INFO] checking keymatrix-0.1.2 against try#7b3565da729099dbe807466fcd118fb2815986e0 for pr-81789
[INFO] extracting crate keymatrix 0.1.2 into /workspace/builds/worker-1/source
[INFO] validating manifest of crates.io crate keymatrix 0.1.2 on toolchain 7b3565da729099dbe807466fcd118fb2815986e0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3565da729099dbe807466fcd118fb2815986e0" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] started tweaking crates.io crate keymatrix 0.1.2
[INFO] finished tweaking crates.io crate keymatrix 0.1.2
[INFO] tweaked toml for crates.io crate keymatrix 0.1.2 written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3565da729099dbe807466fcd118fb2815986e0" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update", kill_on_drop: false }`
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+7b3565da729099dbe807466fcd118fb2815986e0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded cortex-m v0.3.1
[INFO] [stderr]   Downloaded aligned v0.1.2
[INFO] [stderr]   Downloaded atsamd21g18a v0.4.0
[INFO] [stderr]   Downloaded mashup-impl v0.1.12
[INFO] [stderr]   Downloaded cortex-m v0.4.3
[INFO] [stderr]   Downloaded rtfm-syntax v0.3.4
[INFO] [stderr]   Downloaded cortex-m v0.5.11
[INFO] [stderr]   Downloaded untagged-option v0.1.1
[INFO] [stderr]   Downloaded mashup v0.1.12
[INFO] [stderr]   Downloaded cortex-m-rtfm-macros v0.3.2
[INFO] [stderr]   Downloaded atsamd21-hal v0.2.1
[INFO] [stderr]   Downloaded cortex-m-rtfm v0.3.4
[INFO] [stderr]   Downloaded bare-metal v0.1.3
[INFO] [stderr]   Downloaded rtfm-core v0.2.0
[INFO] [stderr]   Downloaded atsamd-hal v0.4.1
[INFO] [stderr]   Downloaded samd21g18a v0.2.1
[INFO] [stderr]   Downloaded atsamd21g18a v0.3.1
[INFO] [stderr]   Downloaded samd21_mini v0.1.2
[INFO] [stderr]   Downloaded panic-abort v0.2.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "+7b3565da729099dbe807466fcd118fb2815986e0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] c53f9a77c784fbc2ba86de9b36183677f55833bfedae7a1467e08cb0078d3b04
[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" "c53f9a77c784fbc2ba86de9b36183677f55833bfedae7a1467e08cb0078d3b04", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "c53f9a77c784fbc2ba86de9b36183677f55833bfedae7a1467e08cb0078d3b04", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c53f9a77c784fbc2ba86de9b36183677f55833bfedae7a1467e08cb0078d3b04", kill_on_drop: false }`
[INFO] [stdout] c53f9a77c784fbc2ba86de9b36183677f55833bfedae7a1467e08cb0078d3b04
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/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" "+7b3565da729099dbe807466fcd118fb2815986e0" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] dd5b5e61e7ad8ff7fa4ad13a23fbde218a0c19f558f3e7b47564c3f3c908b23d
[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" "dd5b5e61e7ad8ff7fa4ad13a23fbde218a0c19f558f3e7b47564c3f3c908b23d", kill_on_drop: false }`
[INFO] [stderr]    Compiling typenum v1.13.0
[INFO] [stderr]    Compiling proc-macro2 v1.0.26
[INFO] [stderr]    Compiling unicode-xid v0.2.1
[INFO] [stderr]     Checking vcell v0.1.3
[INFO] [stderr]    Compiling version_check v0.9.3
[INFO] [stderr]    Compiling syn v1.0.70
[INFO] [stderr]    Compiling cortex-m v0.7.2
[INFO] [stderr]     Checking nb v1.0.0
[INFO] [stderr]     Checking void v1.0.2
[INFO] [stderr]     Checking stable_deref_trait v1.2.0
[INFO] [stderr]    Compiling proc-macro2 v0.4.30
[INFO] [stderr]     Checking bitfield v0.13.2
[INFO] [stderr]    Compiling unicode-xid v0.1.0
[INFO] [stderr]    Compiling cortex-m v0.6.7
[INFO] [stderr]    Compiling autocfg v1.0.1
[INFO] [stderr]    Compiling cortex-m v0.5.11
[INFO] [stderr]     Checking aligned v0.2.0
[INFO] [stderr]    Compiling failure_derive v0.1.8
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]    Compiling cfg-if v1.0.0
[INFO] [stderr]    Compiling proc-macro-hack-impl v0.4.3
[INFO] [stderr]    Compiling cortex-m-rt v0.6.13
[INFO] [stderr]     Checking r0 v0.2.2
[INFO] [stderr]     Checking aligned v0.1.2
[INFO] [stderr]     Checking bare-metal v0.1.3
[INFO] [stderr]    Compiling atsamd21g18a v0.4.0
[INFO] [stderr]    Compiling cortex-m v0.4.3
[INFO] [stderr]    Compiling cortex-m v0.3.1
[INFO] [stderr]    Compiling atsamd21g18a v0.3.1
[INFO] [stderr]    Compiling cortex-m-rtfm v0.3.4
[INFO] [stderr]     Checking untagged-option v0.1.1
[INFO] [stderr]     Checking rtfm-core v0.2.0
[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] [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" "dd5b5e61e7ad8ff7fa4ad13a23fbde218a0c19f558f3e7b47564c3f3c908b23d", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "dd5b5e61e7ad8ff7fa4ad13a23fbde218a0c19f558f3e7b47564c3f3c908b23d", kill_on_drop: false }`
[INFO] [stdout] dd5b5e61e7ad8ff7fa4ad13a23fbde218a0c19f558f3e7b47564c3f3c908b23d