[INFO] fetching crate themelio-node 0.13.2...
[INFO] building themelio-node-0.13.2 against master#ad85bc524b1ad696e42061ad8338d382dffbdbe5 for pr-146237-1
[INFO] extracting crate themelio-node 0.13.2 into /workspace/builds/worker-0-tc1/source
[INFO] removed /workspace/builds/worker-0-tc1/source/rust-toolchain
[INFO] started tweaking crates.io crate themelio-node 0.13.2
[INFO] finished tweaking crates.io crate themelio-node 0.13.2
[INFO] tweaked toml for crates.io crate themelio-node 0.13.2 written to /workspace/builds/worker-0-tc1/source/Cargo.toml
[INFO] validating manifest of crates.io crate themelio-node 0.13.2 on toolchain ad85bc524b1ad696e42061ad8338d382dffbdbe5
[INFO] running `Command { std: CARGO_HOME="/workspace/cargo-home" RUSTUP_HOME="/workspace/rustup-home" "/workspace/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "metadata" "--manifest-path" "Cargo.toml" "--no-deps", kill_on_drop: false }`
[INFO] crate crates.io crate themelio-node 0.13.2 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" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "fetch" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]  Downloading crates ...
[INFO] [stderr]   Downloaded tmelcrypt v0.2.4
[INFO] [stderr]   Downloaded nanorpc-derive v0.1.2
[INFO] [stderr]   Downloaded stdcode v0.1.10
[INFO] [stderr]   Downloaded serde v1.0.145
[INFO] [stderr]   Downloaded nanorand v0.7.0
[INFO] [stderr]   Downloaded proc-macro2 v1.0.47
[INFO] [stderr]   Downloaded wasm-bindgen-shared v0.2.83
[INFO] [stderr]   Downloaded smol v1.2.5
[INFO] [stderr]   Downloaded tracing-futures v0.2.5
[INFO] [stderr]   Downloaded nanorpc v0.1.8
[INFO] [stderr]   Downloaded itoa v1.0.4
[INFO] [stderr]   Downloaded prometheus v0.13.2
[INFO] [stderr]   Downloaded fallible-streaming-iterator v0.1.9
[INFO] [stderr]   Downloaded h2 v0.3.14
[INFO] [stderr]   Downloaded dhat v0.3.1
[INFO] [stderr]   Downloaded imbl v1.0.1
[INFO] [stderr]   Downloaded ipnet v2.5.0
[INFO] [stderr]   Downloaded rusqlite v0.26.3
[INFO] [stderr]   Downloaded hyper-rustls v0.23.0
[INFO] [stderr]   Downloaded headers v0.3.8
[INFO] [stderr]   Downloaded stacker v0.1.15
[INFO] [stderr]   Downloaded imbl-sized-chunks v0.1.1
[INFO] [stderr]   Downloaded pnet_macros v0.28.0
[INFO] [stderr]   Downloaded thousands v0.2.0
[INFO] [stderr]   Downloaded protobuf v2.28.0
[INFO] [stderr]   Downloaded time v0.3.15
[INFO] [stderr]   Downloaded imbl v2.0.0
[INFO] [stderr]   Downloaded async-compat v0.2.1
[INFO] [stderr]   Downloaded default-net v0.6.0
[INFO] [stderr]   Downloaded pnet_macros_support v0.28.0
[INFO] [stderr]   Downloaded raw-cpuid v10.6.0
[INFO] [stderr]   Downloaded pnet_packet v0.28.0
[INFO] [stderr]   Downloaded moka v0.9.4
[INFO] [stderr]   Downloaded structmeta-derive v0.1.5
[INFO] [stderr]   Downloaded lz4_flex v0.8.2
[INFO] [stderr]   Downloaded novasymph v0.3.1
[INFO] [stderr]   Downloaded pnet_sys v0.28.0
[INFO] [stderr]   Downloaded dns-lookup v1.0.8
[INFO] [stderr]   Downloaded trust-dns-client v0.20.4
[INFO] [stderr]   Downloaded boringdb v0.4.1
[INFO] [stderr]   Downloaded pnet_datalink v0.28.0
[INFO] [stderr]   Downloaded web-sys v0.3.60
[INFO] [stderr]   Downloaded ipnetwork v0.18.0
[INFO] [stderr]   Downloaded pnet_base v0.28.0
[INFO] [stderr]   Downloaded crc v2.1.0
[INFO] [stderr]   Downloaded fs2 v0.4.3
[INFO] [stderr]   Downloaded meshanina v0.4.0
[INFO] [stderr]   Downloaded futures-micro v0.5.0
[INFO] [stderr]   Downloaded async-oneshot v0.5.0
[INFO] [stderr]   Downloaded binary-search v0.1.2
[INFO] [stderr]   Downloaded bitmaps v3.2.0
[INFO] [stderr]   Downloaded libsqlite3-sys v0.23.2
[INFO] [stderr]   Downloaded hyper-system-resolver v0.5.0
[INFO] [stderr]   Downloaded data-encoding v2.3.2
[INFO] [stderr]   Downloaded object v0.29.0
[INFO] [stderr]   Downloaded backtrace v0.3.66
[INFO] [stderr]   Downloaded num-bigint v0.4.3
[INFO] [stderr]   Downloaded strsim v0.9.3
[INFO] [stderr]   Downloaded derive_builder_core v0.9.0
[INFO] [stderr]   Downloaded derive_builder v0.9.0
[INFO] [stderr]   Downloaded tokio v1.21.2
[INFO] [stderr]   Downloaded anyhow v1.0.65
[INFO] [stderr]   Downloaded jemalloc-sys v0.3.2
[INFO] [stderr]   Downloaded trust-dns-proto v0.20.4
[INFO] [stderr]   Downloaded webpki-roots v0.22.5
[INFO] [stderr]   Downloaded reqwest v0.11.12
[INFO] [stderr]   Downloaded hyper v0.14.20
[INFO] [stderr]   Downloaded unicode-normalization v0.1.22
[INFO] [stderr]   Downloaded idna v0.3.0
[INFO] [stderr]   Downloaded gimli v0.26.2
[INFO] [stderr]   Downloaded futures-util v0.3.24
[INFO] [stderr]   Downloaded pulldown-cmark v0.9.2
[INFO] [stderr]   Downloaded futures v0.3.24
[INFO] [stderr]   Downloaded multipart v0.18.0
[INFO] [stderr]   Downloaded async-recursion v1.0.0
[INFO] [stderr]   Downloaded lz4_flex v0.9.5
[INFO] [stderr]   Downloaded quanta v0.10.1
[INFO] [stderr]   Downloaded camino v1.1.1
[INFO] [stderr]   Downloaded futures-core v0.3.24
[INFO] [stderr]   Downloaded tabwriter v1.2.1
[INFO] [stderr]   Downloaded num-complex v0.4.2
[INFO] [stderr]   Downloaded blake3 v1.3.1
[INFO] [stderr]   Downloaded rweb-macros v0.14.0
[INFO] [stderr]   Downloaded httpdate v1.0.2
[INFO] [stderr]   Downloaded mime_guess v2.0.4
[INFO] [stderr]   Downloaded sha-1 v0.10.0
[INFO] [stderr]   Downloaded percent-encoding v2.2.0
[INFO] [stderr]   Downloaded warp v0.3.3
[INFO] [stderr]   Downloaded cxx-build v1.0.79
[INFO] [stderr]   Downloaded futures-channel v0.3.24
[INFO] [stderr]   Downloaded futures-macro v0.3.24
[INFO] [stderr]   Downloaded scheduled-thread-pool v0.2.6
[INFO] [stderr]   Downloaded cargo-platform v0.1.2
[INFO] [stderr]   Downloaded triomphe v0.1.8
[INFO] [stderr]   Downloaded reusable-box-future v0.2.0
[INFO] [stderr]   Downloaded smol-timeout v0.6.0
[INFO] [stderr]   Downloaded polling v2.3.0
[INFO] [stderr]   Downloaded spin v0.9.4
[INFO] [stderr]   Downloaded flume v0.10.14
[INFO] [stderr]   Downloaded smolscale v0.3.42
[INFO] [stderr]   Downloaded addr2line v0.17.0
[INFO] [stderr]   Downloaded windows_x86_64_gnu v0.29.0
[INFO] [stderr]   Downloaded termcolor v1.1.3
[INFO] [stderr]   Downloaded genawaiter-macro v0.99.1
[INFO] [stderr]   Downloaded syn-mid v0.5.3
[INFO] [stderr]   Downloaded proc-macro-error v0.4.12
[INFO] [stderr]   Downloaded ahash v0.7.6
[INFO] [stderr]   Downloaded semver v1.0.14
[INFO] [stderr]   Downloaded windows_aarch64_msvc v0.29.0
[INFO] [stderr]   Downloaded parse-display v0.5.5
[INFO] [stderr]   Downloaded windows_x86_64_msvc v0.29.0
[INFO] [stderr]   Downloaded zeroize v1.5.7
[INFO] [stderr]   Downloaded windows_i686_msvc v0.29.0
[INFO] [stderr]   Downloaded rustls-pemfile v1.0.1
[INFO] [stderr]   Downloaded rweb-openapi v0.6.0
[INFO] [stderr]   Downloaded twoway v0.1.8
[INFO] [stderr]   Downloaded tungstenite v0.17.3
[INFO] [stderr]   Downloaded tokio-macros v1.8.0
[INFO] [stderr]   Downloaded tracing-core v0.1.30
[INFO] [stderr]   Downloaded cxx v1.0.79
[INFO] [stderr]   Downloaded nom v7.1.1
[INFO] [stderr]   Downloaded themelio-nodeprot v0.11.5
[INFO] [stderr]   Downloaded unicase v2.6.0
[INFO] [stderr]   Downloaded uuid v1.2.1
[INFO] [stderr]   Downloaded pin-project-lite v0.1.12
[INFO] [stderr]   Downloaded melnet2 v0.1.8
[INFO] [stderr]   Downloaded futures-micro v0.3.1
[INFO] [stderr]   Downloaded async-task v4.3.0
[INFO] [stderr]   Downloaded themelio-nodeprot v0.12.1
[INFO] [stderr]   Downloaded defmac v0.2.1
[INFO] [stderr]   Downloaded miniz_oxide v0.5.4
[INFO] [stderr]   Downloaded bitvec v0.20.4
[INFO] [stderr]   Downloaded dashmap v4.0.2
[INFO] [stderr]   Downloaded novasmt v0.2.19
[INFO] [stderr]   Downloaded arc-swap v1.5.1
[INFO] [stderr]   Downloaded crossbeam-epoch v0.9.11
[INFO] [stderr]   Downloaded crossbeam-deque v0.8.2
[INFO] [stderr]   Downloaded themelio-stf v0.11.12
[INFO] [stderr]   Downloaded num v0.4.0
[INFO] [stderr]   Downloaded once_cell v1.15.0
[INFO] [stderr]   Downloaded aho-corasick v0.7.19
[INFO] [stderr]   Downloaded thiserror-impl v1.0.37
[INFO] [stderr]   Downloaded thiserror v1.0.37
[INFO] [stderr]   Downloaded themelio-structs v0.2.10
[INFO] [stderr]   Downloaded arrayvec v0.7.2
[INFO] [stderr]   Downloaded block-buffer v0.10.3
[INFO] [stderr]   Downloaded jemallocator-global v0.3.2
[INFO] [stderr]   Downloaded enum-as-inner v0.3.4
[INFO] [stderr]   Downloaded windows_i686_gnu v0.29.0
[INFO] [stderr]   Downloaded public-ip v0.2.2
[INFO] [stderr]   Downloaded wasm-bindgen-futures v0.4.33
[INFO] [stderr]   Downloaded fallible-iterator v0.2.0
[INFO] [stderr]   Downloaded pmutil v0.5.3
[INFO] [stderr]   Downloaded http-body v0.4.5
[INFO] [stderr]   Downloaded buf_redux v0.8.4
[INFO] [stderr]   Downloaded sct v0.7.0
[INFO] [stderr]   Downloaded webpki v0.22.0
[INFO] [stderr]   Downloaded tokio-rustls v0.23.4
[INFO] [stderr]   Downloaded form_urlencoded v1.1.0
[INFO] [stderr]   Downloaded tokio-tungstenite v0.17.2
[INFO] [stderr]   Downloaded tracing-attributes v0.1.23
[INFO] [stderr]   Downloaded cxxbridge-macro v1.0.79
[INFO] [stderr]   Downloaded codespan-reporting v0.11.1
[INFO] [stderr]   Downloaded iana-time-zone-haiku v0.1.1
[INFO] [stderr]   Downloaded themelio-bootstrap v0.6.1
[INFO] [stderr]   Downloaded env_logger v0.8.4
[INFO] [stderr]   Downloaded melnet v0.2.27
[INFO] [stderr]   Downloaded futures-task v0.3.24
[INFO] [stderr]   Downloaded bytecount v0.6.3
[INFO] [stderr]   Downloaded async-trait v0.1.57
[INFO] [stderr]   Downloaded async-channel v1.7.1
[INFO] [stderr]   Downloaded socket2 v0.4.7
[INFO] [stderr]   Downloaded async-io v1.9.0
[INFO] [stderr]   Downloaded pin-project-internal v1.0.12
[INFO] [stderr]   Downloaded assoc v0.1.2
[INFO] [stderr]   Downloaded catvec v0.1.6
[INFO] [stderr]   Downloaded jemallocator v0.3.2
[INFO] [stderr]   Downloaded melpow v0.1.1
[INFO] [stderr]   Downloaded funty v1.1.0
[INFO] [stderr]   Downloaded radium v0.6.2
[INFO] [stderr]   Downloaded wyz v0.2.0
[INFO] [stderr]   Downloaded env_logger v0.9.1
[INFO] [stderr]   Downloaded proc-macro-error-attr v0.4.12
[INFO] [stderr]   Downloaded genawaiter-proc-macro v0.99.1
[INFO] [stderr]   Downloaded genawaiter v0.99.1
[INFO] [stderr]   Downloaded honggfuzz v0.5.55
[INFO] [stderr]   Downloaded js-sys v0.3.60
[INFO] [stderr]   Downloaded wasm-bindgen-macro-support v0.2.83
[INFO] [stderr]   Downloaded wasm-bindgen v0.2.83
[INFO] [stderr]   Downloaded lru v0.7.8
[INFO] [stderr]   Downloaded either v1.8.0
[INFO] [stderr]   Downloaded crossbeam-utils v0.8.12
[INFO] [stderr]   Downloaded structmeta v0.1.5
[INFO] [stderr]   Downloaded arbitrary v1.1.7
[INFO] [stderr]   Downloaded base32 v0.4.0
[INFO] [stderr]   Downloaded digest v0.10.5
[INFO] [stderr]   Downloaded ed25519 v1.5.2
[INFO] [stderr]   Downloaded cpufeatures v0.2.5
[INFO] [stderr]   Downloaded encoding_rs v0.8.31
[INFO] [stderr]   Downloaded mime v0.3.16
[INFO] [stderr]   Downloaded rustls v0.20.6
[INFO] [stderr]   Downloaded cxxbridge-flags v1.0.79
[INFO] [stderr]   Downloaded scratch v1.0.2
[INFO] [stderr]   Downloaded chrono v0.4.22
[INFO] [stderr]   Downloaded serde_json v1.0.86
[INFO] [stderr]   Downloaded blocking v1.2.0
[INFO] [stderr]   Downloaded async-global-executor v2.3.0
[INFO] [stderr]   Downloaded async-oneshot v0.4.2
[INFO] [stderr]   Downloaded cache-padded v1.2.0
[INFO] [stderr]   Downloaded dashmap v5.4.0
[INFO] [stderr]   Downloaded futures-sink v0.3.24
[INFO] [stderr]   Downloaded pin-project v1.0.12
[INFO] [stderr]   Downloaded mio v0.8.4
[INFO] [stderr]   Downloaded tokio-util v0.7.4
[INFO] [stderr]   Downloaded tracing v0.1.37
[INFO] [stderr]   Downloaded async-net v1.7.0
[INFO] [stderr]   Downloaded async-process v1.5.0
[INFO] [stderr]   Downloaded async-lock v2.5.0
[INFO] [stderr]   Downloaded wasm-bindgen-backend v0.2.83
[INFO] [stderr]   Downloaded wasm-bindgen-macro v0.2.83
[INFO] [stderr]   Downloaded futures-executor v0.3.24
[INFO] [stderr]   Downloaded rustls-pemfile v0.2.1
[INFO] [stderr]   Downloaded tokio-stream v0.1.11
[INFO] [stderr]   Downloaded url v2.3.1
[INFO] [stderr]   Downloaded rweb v0.15.0
[INFO] [stderr]   Downloaded link-cplusplus v1.0.7
[INFO] [stderr]   Downloaded systemstat v0.1.12
[INFO] [stderr]   Downloaded tagptr v0.2.0
[INFO] [stderr]   Downloaded memmap2 v0.5.7
[INFO] [stderr]   Downloaded iana-time-zone v0.1.51
[INFO] [stderr]   Downloaded smol_str v0.1.23
[INFO] [stderr]   Downloaded libc v0.2.135
[INFO] [stderr]   Downloaded syn v1.0.102
[INFO] [stderr]   Downloaded unicode-ident v1.0.5
[INFO] [stderr]   Downloaded serde_derive v1.0.145
[INFO] [stderr]   Downloaded futures-io v0.3.24
[INFO] [stderr]   Downloaded atomic_float v0.1.0
[INFO] [stderr]   Downloaded fs_extra v1.2.0
[INFO] [stderr]   Downloaded ethnum v1.3.0
[INFO] [stderr]   Downloaded replace_with v0.1.7
[INFO] [stderr]   Downloaded parse-display-derive v0.5.5
[INFO] [stderr]   Downloaded derive_arbitrary v1.1.6
[INFO] [stderr]   Downloaded arrayref v0.3.6
[INFO] [stderr]   Downloaded zeroize_derive v1.3.2
[INFO] [stderr]   Downloaded serde-big-array v0.3.3
[INFO] [stderr]   Downloaded windows v0.29.0
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stdout] a1b67f331f50bfe157fc1ced455787a14c8a1a4cf110c5733affbb3515d85c9a
[INFO] running `Command { std: "docker" "start" "-a" "a1b67f331f50bfe157fc1ced455787a14c8a1a4cf110c5733affbb3515d85c9a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "a1b67f331f50bfe157fc1ced455787a14c8a1a4cf110c5733affbb3515d85c9a", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "a1b67f331f50bfe157fc1ced455787a14c8a1a4cf110c5733affbb3515d85c9a", kill_on_drop: false }`
[INFO] [stdout] a1b67f331f50bfe157fc1ced455787a14c8a1a4cf110c5733affbb3515d85c9a
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-tc1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-0-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:e90291280db7d1fac5b66fc6dad9f9662629e7365a55743daf9bdf73ebc4ea79" "/opt/rustwide/cargo-home/bin/cargo" "+ad85bc524b1ad696e42061ad8338d382dffbdbe5" "build" "--frozen" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] c859483f2d8fe658132ec0964bcc7eb706fcb86893cf55a9e91fd6322d2be642
[INFO] running `Command { std: "docker" "start" "-a" "c859483f2d8fe658132ec0964bcc7eb706fcb86893cf55a9e91fd6322d2be642", kill_on_drop: false }`
[INFO] [stderr]    Compiling libc v0.2.135
[INFO] [stderr]    Compiling cfg-if v1.0.0
[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 v1.0.102
[INFO] [stderr]    Compiling version_check v0.9.4
[INFO] [stderr]    Compiling cc v1.0.73
[INFO] [stderr]    Compiling memchr v2.5.0
[INFO] [stderr]    Compiling once_cell v1.15.0
[INFO] [stderr]    Compiling serde_derive v1.0.145
[INFO] [stderr]    Compiling serde v1.0.145
[INFO] [stderr]    Compiling futures-core v0.3.24
[INFO] [stderr]    Compiling log v0.4.17
[INFO] [stderr]    Compiling typenum v1.15.0
[INFO] [stderr]    Compiling scopeguard v1.1.0
[INFO] [stderr]    Compiling pin-project-lite v0.2.9
[INFO] [stderr]    Compiling fastrand v1.8.0
[INFO] [stderr]    Compiling lock_api v0.4.9
[INFO] [stderr]    Compiling smallvec v1.10.0
[INFO] [stderr]    Compiling crossbeam-utils v0.8.12
[INFO] [stderr]    Compiling parking v2.0.0
[INFO] [stderr]    Compiling futures-io v0.3.24
[INFO] [stdout] error[E0635]: unknown feature `proc_macro_span_shrink`
[INFO] [stdout]   --> /opt/rustwide/cargo-home/registry/src/index.crates.io-1949cf8c6b5b557f/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] [stderr]    Compiling cache-padded v1.2.0
[INFO] [stderr]    Compiling waker-fn v1.1.0
[INFO] [stderr]    Compiling memoffset v0.6.5
[INFO] [stderr]    Compiling concurrent-queue v1.2.4
[INFO] [stdout] For more information about this error, try `rustc --explain E0635`.
[INFO] [stdout] 
[INFO] [stderr]    Compiling slab v0.4.7
[INFO] [stderr] error: could not compile `proc-macro2` (lib) due to 1 previous error
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] running `Command { std: "docker" "inspect" "c859483f2d8fe658132ec0964bcc7eb706fcb86893cf55a9e91fd6322d2be642", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "c859483f2d8fe658132ec0964bcc7eb706fcb86893cf55a9e91fd6322d2be642", kill_on_drop: false }`
[INFO] [stdout] c859483f2d8fe658132ec0964bcc7eb706fcb86893cf55a9e91fd6322d2be642