[INFO] updating cached repository 1521350289/study_rust
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/1521350289/study_rust
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/1521350289/study_rust" "work/ex/beta-1.37-6/sources/1.36.0/gh/1521350289/study_rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/1.36.0/gh/1521350289/study_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/1521350289/study_rust" "work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/1521350289/study_rust"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.37-6/sources/beta-2019-07-23/gh/1521350289/study_rust'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] fe3ea32740d5ce399159506be726428505bdc798
[INFO] sha for GitHub repo 1521350289/study_rust: fe3ea32740d5ce399159506be726428505bdc798
[INFO] validating manifest of 1521350289/study_rust on toolchain 1.36.0
[ERROR] this task or one of its parent failed!
[ERROR] overridden task result to broken:cargo-toml
[ERROR] caused by: missing Cargo.toml for 1521350289/study_rust
[ERROR]