[INFO] crate combinatorics 0.0.1 is already in cache
[INFO] extracting crate combinatorics 0.0.1 into work/ex/pr-58948/sources/master#0f88167f89fffe321590c5148f21b7d51d44388d/reg/combinatorics/0.0.1
[INFO] extracting crate combinatorics 0.0.1 into work/ex/pr-58948/sources/try#a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b/reg/combinatorics/0.0.1
[INFO] validating manifest of combinatorics-0.0.1 on toolchain master#0f88167f89fffe321590c5148f21b7d51d44388d
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+0f88167f89fffe321590c5148f21b7d51d44388d-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of combinatorics-0.0.1 on toolchain try#a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing combinatorics-0.0.1
[INFO] finished frobbing combinatorics-0.0.1
[INFO] frobbed toml for combinatorics-0.0.1 written to work/ex/pr-58948/sources/master#0f88167f89fffe321590c5148f21b7d51d44388d/reg/combinatorics/0.0.1/Cargo.toml
[INFO] started frobbing combinatorics-0.0.1
[INFO] finished frobbing combinatorics-0.0.1
[INFO] frobbed toml for combinatorics-0.0.1 written to work/ex/pr-58948/sources/try#a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b/reg/combinatorics/0.0.1/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+0f88167f89fffe321590c5148f21b7d51d44388d-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+0f88167f89fffe321590c5148f21b7d51d44388d-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+a829e31f924ec11e400e8d0c2fd2c4bb8937ae6b-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] checking combinatorics-0.0.1 against master#0f88167f89fffe321590c5148f21b7d51d44388d for pr-58948
[INFO] running `"docker" "create" "-v" "/mnt/big/crater/work/local/target-dirs/pr-58948/worker-6/master#0f88167f89fffe321590c5148f21b7d51d44388d:/opt/crater/target:rw,Z" "-v" "/mnt/big/crater/work/ex/pr-58948/sources/master#0f88167f89fffe321590c5148f21b7d51d44388d/reg/combinatorics/0.0.1:/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" "+0f88167f89fffe321590c5148f21b7d51d44388d-alt" "check" "--frozen" "--all" "--all-targets"`
[INFO] [stdout] 50a2236539c0ab549b28b6a032d54215051d35390455003f407c6658a29961fd
[INFO] running `"docker" "start" "-a" "50a2236539c0ab549b28b6a032d54215051d35390455003f407c6658a29961fd"`
[INFO] [stderr]     Checking combinatorics v0.0.1 (/opt/crater/workdir)
[INFO] [stderr] error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
[INFO] [stderr]   --> src/lib.rs:29:1
[INFO] [stderr]    |
[INFO] [stderr] 29 | extern crate libc;
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: add #![feature(rustc_private)] 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 `combinatorics`.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error[E0658]: use of unstable library feature 'rustc_private': this crate is being loaded from the sysroot, an unstable location; did you mean to load this crate from crates.io via `Cargo.toml` instead? (see issue #27812)
[INFO] [stderr]   --> src/lib.rs:29:1
[INFO] [stderr]    |
[INFO] [stderr] 29 | extern crate libc;
[INFO] [stderr]    | ^^^^^^^^^^^^^^^^^^
[INFO] [stderr]    |
[INFO] [stderr]    = help: add #![feature(rustc_private)] 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 `combinatorics`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] running `"docker" "inspect" "50a2236539c0ab549b28b6a032d54215051d35390455003f407c6658a29961fd"`
[INFO] running `"docker" "rm" "-f" "50a2236539c0ab549b28b6a032d54215051d35390455003f407c6658a29961fd"`
[INFO] [stdout] 50a2236539c0ab549b28b6a032d54215051d35390455003f407c6658a29961fd