[INFO] updating cached repository rust-lang-nursery/polonius
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/rust-lang-nursery/polonius
[INFO] [stderr]  * branch                  HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/rust-lang-nursery/polonius" "work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/rust-lang-nursery/polonius"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/rust-lang-nursery/polonius'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/rust-lang-nursery/polonius" "work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/rust-lang-nursery/polonius"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/rust-lang-nursery/polonius'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 3f122afd019f9a4be0ce1d7e2844e52b0faf3c24
[INFO] sha for GitHub repo rust-lang-nursery/polonius: 3f122afd019f9a4be0ce1d7e2844e52b0faf3c24
[INFO] validating manifest of rust-lang-nursery/polonius 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 rust-lang-nursery/polonius 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 rust-lang-nursery/polonius
[INFO] removed workspace from rust-lang-nursery/polonius
[INFO] removed path dependency polonius-engine from rust-lang-nursery/polonius
[INFO] removed path dependency polonius-parser from rust-lang-nursery/polonius
[INFO] finished frobbing rust-lang-nursery/polonius
[INFO] frobbed toml for rust-lang-nursery/polonius written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/rust-lang-nursery/polonius/Cargo.toml
[INFO] started frobbing rust-lang-nursery/polonius
[INFO] removed workspace from rust-lang-nursery/polonius
[INFO] removed path dependency polonius-engine from rust-lang-nursery/polonius
[INFO] removed path dependency polonius-parser from rust-lang-nursery/polonius
[INFO] finished frobbing rust-lang-nursery/polonius
[INFO] frobbed toml for rust-lang-nursery/polonius written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/rust-lang-nursery/polonius/Cargo.toml
[INFO] crate rust-lang-nursery/polonius 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] [stderr]     Blocking waiting for file lock on package cache
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr] error: failed to select a version for the requirement `polonius-parser = "^0.3.0"`
[INFO] [stderr]   candidate versions found which didn't match: 0.2.0, 0.1.0
[INFO] [stderr]   location searched: crates.io index
[INFO] [stderr] required by package `polonius v0.4.0 (/mnt/big/crater/work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/rust-lang-nursery/polonius)`
[ERROR] this task or one of its parent failed!
[ERROR] command `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+60960a260f7b5c695fd0717311d72ce62dd4eb43-alt" "fetch" "--locked" "--manifest-path" "Cargo.toml"` failed