[INFO] crate volatile_cell 1.0.0 is already in cache
[INFO] extracting crate volatile_cell 1.0.0 into work/ex/pr-56955/sources/master#d99a320cba42f661aebfa1293b7b2ec3603dda75/reg/volatile_cell/1.0.0
[INFO] extracting crate volatile_cell 1.0.0 into work/ex/pr-56955/sources/try#e70472fc501b855c9080f3772432c10fe20b8866/reg/volatile_cell/1.0.0
[INFO] validating manifest of volatile_cell-1.0.0 on toolchain master#d99a320cba42f661aebfa1293b7b2ec3603dda75
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+d99a320cba42f661aebfa1293b7b2ec3603dda75-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of volatile_cell-1.0.0 on toolchain try#e70472fc501b855c9080f3772432c10fe20b8866
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+e70472fc501b855c9080f3772432c10fe20b8866-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-56955/sources/master#d99a320cba42f661aebfa1293b7b2ec3603dda75/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-56955/sources/try#e70472fc501b855c9080f3772432c10fe20b8866/reg/volatile_cell/1.0.0/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+d99a320cba42f661aebfa1293b7b2ec3603dda75-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-56955/sources/master#d99a320cba42f661aebfa1293b7b2ec3603dda75/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" "+d99a320cba42f661aebfa1293b7b2ec3603dda75-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"` failed