[INFO] updating cached repository Ibexian/char_predictor
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/Ibexian/char_predictor
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/Ibexian/char_predictor" "work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/Ibexian/char_predictor"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/Ibexian/char_predictor'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/Ibexian/char_predictor" "work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/Ibexian/char_predictor"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/Ibexian/char_predictor'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 4a75007895fc1f57326754287a21332c038fdf0f
[INFO] sha for GitHub repo Ibexian/char_predictor: 4a75007895fc1f57326754287a21332c038fdf0f
[INFO] validating manifest of Ibexian/char_predictor on toolchain master#60960a260f7b5c695fd0717311d72ce62dd4eb43
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of Ibexian/char_predictor on toolchain try#266783e4e09e4e9d5307c1c8e695659c58bbcac7
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing Ibexian/char_predictor
[INFO] finished frobbing Ibexian/char_predictor
[INFO] frobbed toml for Ibexian/char_predictor written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/Ibexian/char_predictor/Cargo.toml
[INFO] started frobbing Ibexian/char_predictor
[INFO] finished frobbing Ibexian/char_predictor
[INFO] frobbed toml for Ibexian/char_predictor written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/Ibexian/char_predictor/Cargo.toml
[INFO] crate Ibexian/char_predictor already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking Ibexian/char_predictor against try#266783e4e09e4e9d5307c1c8e695659c58bbcac7 for pr-63376
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-63376/worker-0/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/Ibexian/char_predictor:/opt/crater/workdir:ro,Z" "-v" "/mnt/big/crater/work/local/cargo-home:/opt/crater/cargo-home:ro,Z" "-v" "/mnt/big/crater/work/local/rustup-home:/opt/crater/rustup-home:ro,Z" "-e" "USER_ID=1000" "-e" "SOURCE_DIR=/opt/crater/workdir" "-e" "MAP_USER_ID=1000" "-e" "CARGO_TARGET_DIR=/opt/crater/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTFLAGS=--cap-lints=forbid" "-e" "CARGO_HOME=/opt/crater/cargo-home" "-e" "RUSTUP_HOME=/opt/crater/rustup-home" "-w" "/opt/crater/workdir" "-m" "1536M" "--network" "none" "rustops/crates-build-env" "/opt/crater/cargo-home/bin/cargo" "+266783e4e09e4e9d5307c1c8e695659c58bbcac7-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 508ab72b2278f7676461f9c191e393d5d930f0617b381b12488231e88b94c7d4
[INFO] running `"docker" "start" "-a" "508ab72b2278f7676461f9c191e393d5d930f0617b381b12488231e88b94c7d4"`
[INFO] [stderr]    Compiling cc v1.0.20
[INFO] [stderr]    Compiling serde v1.0.74
[INFO] [stderr]    Compiling ryu v0.2.5
[INFO] [stderr]    Compiling socket2 v0.3.7
[INFO] [stderr]    Compiling proc-macro2 v0.4.13
[INFO] [stderr]    Compiling tar v0.4.16
[INFO] [stderr]     Checking num-complex v0.1.43
[INFO] [stderr]     Checking aligned_alloc v0.1.3
[INFO] [stderr] error[E0658]: use of unstable library feature 'proc_macro_def_site'
[INFO] [stderr]    --> /opt/crater/cargo-home/registry/src/github.com-1ecc6299db9ec823/proc-macro2-0.4.13/src/unstable.rs:359:27
[INFO] [stderr]     |
[INFO] [stderr] 359 |             Span::Nightly(proc_macro::Span::def_site())
[INFO] [stderr]     |                           ^^^^^^^^^^^^^^^^^^^^^^^^^^
[INFO] [stderr]     |
[INFO] [stderr]     = note: for more information, see https://github.com/rust-lang/rust/issues/54724
[INFO] [stderr]     = help: add `#![feature(proc_macro_def_site)]` to the crate attributes to enable
[INFO] [stderr] 
[INFO] [stderr] error: aborting due to previous error
[INFO] [stderr] 
[INFO] [stderr] For more information about this error, try `rustc --explain E0658`.
[INFO] [stderr] error: Could not compile `proc-macro2`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `"docker" "inspect" "508ab72b2278f7676461f9c191e393d5d930f0617b381b12488231e88b94c7d4"`
[INFO] running `"docker" "rm" "-f" "508ab72b2278f7676461f9c191e393d5d930f0617b381b12488231e88b94c7d4"`
[INFO] [stdout] 508ab72b2278f7676461f9c191e393d5d930f0617b381b12488231e88b94c7d4