[INFO] cloning repository https://github.com/sornas/arduino-uno-uart
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/sornas/arduino-uno-uart" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsornas%2Farduino-uno-uart", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsornas%2Farduino-uno-uart'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] cde61643be338ac2136bff9acf6a4fbfbb2219f8
[INFO] checking sornas/arduino-uno-uart/cde61643be338ac2136bff9acf6a4fbfbb2219f8 against master#bbefc9837f4157cc09ed60e6d7b21e345d582dd9 for pr-114571-3
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fsornas%2Farduino-uno-uart" "/workspace/builds/worker-7-tc1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-7-tc1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/sornas/arduino-uno-uart on toolchain bbefc9837f4157cc09ed60e6d7b21e345d582dd9
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+bbefc9837f4157cc09ed60e6d7b21e345d582dd9" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] removed /workspace/builds/worker-7-tc1/source/.cargo/config.toml
[INFO] removed /workspace/builds/worker-7-tc1/source/rust-toolchain.toml
[INFO] started tweaking git repo https://github.com/sornas/arduino-uno-uart
[INFO] finished tweaking git repo https://github.com/sornas/arduino-uno-uart
[INFO] tweaked toml for git repo https://github.com/sornas/arduino-uno-uart written to /workspace/builds/worker-7-tc1/source/Cargo.toml
[INFO] crate git repo https://github.com/sornas/arduino-uno-uart already has a lockfile, it will not be regenerated
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+bbefc9837f4157cc09ed60e6d7b21e345d582dd9" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded avr-device-macros v0.4.0
[INFO] [stderr]   Downloaded avr-device v0.4.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+bbefc9837f4157cc09ed60e6d7b21e345d582dd9" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] 7ef6de976c0d2d975e4fb8bc60e54486b856e3cc0f1243877ac49f3840e4553a
[INFO] running `Command { std: "docker" "start" "-a" "7ef6de976c0d2d975e4fb8bc60e54486b856e3cc0f1243877ac49f3840e4553a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "7ef6de976c0d2d975e4fb8bc60e54486b856e3cc0f1243877ac49f3840e4553a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "7ef6de976c0d2d975e4fb8bc60e54486b856e3cc0f1243877ac49f3840e4553a", kill_on_drop: false }`
[INFO] [stdout] 7ef6de976c0d2d975e4fb8bc60e54486b856e3cc0f1243877ac49f3840e4553a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-7-tc1/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" "RUSTDOCFLAGS=--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@sha256:2788e3201cd34a07e3172128adcd8b3090168a8e3bcc40d7c032b9dda1df7d1c" "/opt/rustwide/cargo-home/bin/cargo" "+bbefc9837f4157cc09ed60e6d7b21e345d582dd9" "check" "--frozen" "--all" "--all-targets" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] ec38b54d125614dff0f30984fa643d24188c02a88f5832b59a8cab5aac157fb2
[INFO] running `Command { std: "docker" "start" "-a" "ec38b54d125614dff0f30984fa643d24188c02a88f5832b59a8cab5aac157fb2", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v1.0.47
[INFO] [stderr]    Compiling quote v1.0.21
[INFO] [stderr]    Compiling unicode-ident v1.0.5
[INFO] [stderr]    Compiling syn v1.0.105
[INFO] [stderr]    Compiling proc-macro-hack v0.5.19
[INFO] [stderr]    Compiling rustversion v1.0.9
[INFO] [stderr]     Checking nb v1.0.0
[INFO] [stderr]     Checking void v1.0.2
[INFO] [stderr]     Checking nb v0.1.3
[INFO] [stderr]     Checking cfg-if v0.1.10
[INFO] [stderr]     Checking embedded-hal v0.2.7
[INFO] [stderr]     Checking bare-metal v1.0.0
[INFO] [stderr]     Checking vcell v0.1.3
[INFO] [stderr]     Checking ufmt-write v0.1.0
[INFO] [stderr]    Compiling paste v1.0.9
[INFO] [stderr]     Checking cfg-if v1.0.0
[INFO] [stderr]     Checking bitbang-hal v0.3.2 (/opt/rustwide/workdir/vendor/bitbang-hal)
[INFO] [stderr]     Checking panic-halt v0.2.0
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-6f17d22bba15001f/proc-macro2-1.0.47/src/lib.rs:92:30
[INFO] [stdout]    |
[INFO] [stdout] 92 |     feature(proc_macro_span, proc_macro_span_shrink)
[INFO] [stdout]    |                              ^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to 1 previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `proc-macro2` (lib) due to 2 previous errors
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "ec38b54d125614dff0f30984fa643d24188c02a88f5832b59a8cab5aac157fb2", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "ec38b54d125614dff0f30984fa643d24188c02a88f5832b59a8cab5aac157fb2", kill_on_drop: false }`
[INFO] [stdout] ec38b54d125614dff0f30984fa643d24188c02a88f5832b59a8cab5aac157fb2