[INFO] updating cached repository corvuslang/corvus_ruby
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/corvuslang/corvus_ruby
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/corvuslang/corvus_ruby" "work/ex/beta-1.38-1/sources/1.37.0/gh/corvuslang/corvus_ruby"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/1.37.0/gh/corvuslang/corvus_ruby'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/corvuslang/corvus_ruby" "work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/corvuslang/corvus_ruby"`
[INFO] [stderr] Cloning into 'work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/corvuslang/corvus_ruby'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] 7cef6b7f988b4519e104f345a010399f4ff07121
[INFO] sha for GitHub repo corvuslang/corvus_ruby: 7cef6b7f988b4519e104f345a010399f4ff07121
[INFO] validating manifest of corvuslang/corvus_ruby on toolchain 1.37.0
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] validating manifest of corvuslang/corvus_ruby on toolchain beta-2019-08-13
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+beta-2019-08-13" "read-manifest" "--manifest-path" "Cargo.toml"`
[INFO] started frobbing corvuslang/corvus_ruby
[INFO] finished frobbing corvuslang/corvus_ruby
[INFO] frobbed toml for corvuslang/corvus_ruby written to work/ex/beta-1.38-1/sources/1.37.0/gh/corvuslang/corvus_ruby/Cargo.toml
[INFO] started frobbing corvuslang/corvus_ruby
[INFO] finished frobbing corvuslang/corvus_ruby
[INFO] frobbed toml for corvuslang/corvus_ruby written to work/ex/beta-1.38-1/sources/beta-2019-08-13/gh/corvuslang/corvus_ruby/Cargo.toml
[INFO] crate corvuslang/corvus_ruby already has a lockfile, it will not be regenerated
[INFO] running `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"`
[INFO] [stderr]     Updating git repository `https://github.com/corvuslang/corvus_core`
[INFO] [stderr] error: failed to load source for a dependency on `corvus_core`
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   Unable to update https://github.com/corvuslang/corvus_core?branch=develop#ce6cab5a
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   failed to fetch into /mnt/big/crater/work/local/cargo-home/git/db/corvus_core-dd8dd3860b6bae47
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   failed to authenticate when downloading repository
[INFO] [stderr] attempted to find username/password via git's `credential.helper` support, but failed
[INFO] [stderr] 
[INFO] [stderr] Caused by:
[INFO] [stderr]   failed to acquire username/password from local configuration
[ERROR] this task or one of its parent failed!
[ERROR] command `"/mnt/big/crater/work/local/cargo-home/bin/cargo" "+1.37.0" "fetch" "--locked" "--manifest-path" "Cargo.toml"` failed