[INFO] crate u2f 0.1.2 is already in cache
[INFO] extracting crate u2f 0.1.2 into work/ex/pr-57745/sources/master#f613dc138b4012cf3d2eb40718fbcc7cf0a34039/reg/u2f/0.1.2
[INFO] extracting crate u2f 0.1.2 into work/ex/pr-57745/sources/try#29640c57b5f92febba0e40c50cb863c9a7ede51d/reg/u2f/0.1.2
[INFO] validating manifest of u2f-0.1.2 on toolchain master#f613dc138b4012cf3d2eb40718fbcc7cf0a34039
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+f613dc138b4012cf3d2eb40718fbcc7cf0a34039-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of u2f-0.1.2 on toolchain try#29640c57b5f92febba0e40c50cb863c9a7ede51d
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+29640c57b5f92febba0e40c50cb863c9a7ede51d-alt" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing u2f-0.1.2
[INFO] finished frobbing u2f-0.1.2
[INFO] frobbed toml for u2f-0.1.2 written to work/ex/pr-57745/sources/master#f613dc138b4012cf3d2eb40718fbcc7cf0a34039/reg/u2f/0.1.2/Cargo.toml
[INFO] started frobbing u2f-0.1.2
[INFO] finished frobbing u2f-0.1.2
[INFO] frobbed toml for u2f-0.1.2 written to work/ex/pr-57745/sources/try#29640c57b5f92febba0e40c50cb863c9a7ede51d/reg/u2f/0.1.2/Cargo.toml
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+f613dc138b4012cf3d2eb40718fbcc7cf0a34039-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"`
[INFO] [stderr] error: failed to select a version for the requirement `ring = "^0.11.0"`
[INFO] [stderr]   candidate versions found which didn't match: 0.14.2, 0.14.1, 0.14.0, ...
[INFO] [stderr]   location searched: crates.io index
[INFO] [stderr] required by package `u2f v0.1.2 (/mnt/big/crater/work/ex/pr-57745/sources/master#f613dc138b4012cf3d2eb40718fbcc7cf0a34039/reg/u2f/0.1.2)`
[ERROR] this task or one of its parent failed!
[ERROR] command `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+f613dc138b4012cf3d2eb40718fbcc7cf0a34039-alt" "generate-lockfile" "--manifest-path" "Cargo.toml" "-Zno-index-update"` failed