[INFO] fetching crate volatile_cell 1.0.0...
[INFO] extracting crate volatile_cell 1.0.0 into work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/reg/volatile_cell/1.0.0
[INFO] extracting crate volatile_cell 1.0.0 into work/ex/pr-61629/sources/try#e212b7d492c96d3837691ba29d32d5f468933fb8/reg/volatile_cell/1.0.0
[INFO] validating manifest of volatile_cell-1.0.0 on toolchain master#c8865d8e195813ade6b84434ac9f8850e7112d1a
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of volatile_cell-1.0.0 on toolchain try#e212b7d492c96d3837691ba29d32d5f468933fb8
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e212b7d492c96d3837691ba29d32d5f468933fb8-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing volatile_cell-1.0.0
[INFO] finished frobbing volatile_cell-1.0.0
[INFO] frobbed toml for volatile_cell-1.0.0 written to work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/reg/volatile_cell/1.0.0/Cargo.toml
[INFO] started frobbing volatile_cell-1.0.0
[INFO] finished frobbing volatile_cell-1.0.0
[INFO] frobbed toml for volatile_cell-1.0.0 written to work/ex/pr-61629/sources/try#e212b7d492c96d3837691ba29d32d5f468933fb8/reg/volatile_cell/1.0.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr]     Updating git repository `https://github.com/hackndev/rust-libcore`
[INFO] [stderr] error: no matching package named `core` found
[INFO] [stderr] location searched: https://github.com/hackndev/rust-libcore
[INFO] [stderr] required by package `volatile_cell v1.0.0 (/mnt/big/crater/work/ex/pr-61629/sources/master#c8865d8e195813ade6b84434ac9f8850e7112d1a/reg/volatile_cell/1.0.0)`
[ERROR] this task or one of its parent failed!
[ERROR] command `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+c8865d8e195813ade6b84434ac9f8850e7112d1a-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"` failed