[INFO] updating cached repository philippkeller/shell_doctest
[INFO] running `"git" "fetch" "--all"`
[INFO] [stdout] Fetching origin
[INFO] [stderr] From git://github.com/philippkeller/shell_doctest
[INFO] [stderr]  * branch            HEAD       -> FETCH_HEAD
[INFO] running `"git" "clone" "work/cache/sources/gh/philippkeller/shell_doctest" "work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/philippkeller/shell_doctest"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/philippkeller/shell_doctest'...
[INFO] [stderr] done.
[INFO] running `"git" "clone" "work/cache/sources/gh/philippkeller/shell_doctest" "work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/philippkeller/shell_doctest"`
[INFO] [stderr] Cloning into 'work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/philippkeller/shell_doctest'...
[INFO] [stderr] done.
[INFO] running `"git" "rev-parse" "HEAD"`
[INFO] [stdout] ae6b64b4fb694c18dae90acabdc1bda2f4a1dd28
[INFO] sha for GitHub repo philippkeller/shell_doctest: ae6b64b4fb694c18dae90acabdc1bda2f4a1dd28
[INFO] validating manifest of philippkeller/shell_doctest 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 philippkeller/shell_doctest 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 philippkeller/shell_doctest
[INFO] finished frobbing philippkeller/shell_doctest
[INFO] frobbed toml for philippkeller/shell_doctest written to work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/philippkeller/shell_doctest/Cargo.toml
[INFO] started frobbing philippkeller/shell_doctest
[INFO] finished frobbing philippkeller/shell_doctest
[INFO] frobbed toml for philippkeller/shell_doctest written to work/ex/pr-63376/sources/try#266783e4e09e4e9d5307c1c8e695659c58bbcac7/gh/philippkeller/shell_doctest/Cargo.toml
[INFO] crate philippkeller/shell_doctest 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]     Updating git repository `https://github.com/philippkeller/rexpect`
[INFO] [stderr]     Updating crates.io index
[INFO] [stderr] error: failed to select a version for `libc`.
[INFO] [stderr]     ... required by package `nix v0.14.0`
[INFO] [stderr]     ... which is depended on by `rexpect v0.3.0 (https://github.com/philippkeller/rexpect#30bfb3ed)`
[INFO] [stderr]     ... which is depended on by `shell_doctest v0.1.0 (/mnt/big/crater/work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/philippkeller/shell_doctest)`
[INFO] [stderr] versions that meet the requirements `^0.2.55` are: 0.2.61, 0.2.60, 0.2.59, 0.2.58, 0.2.57, 0.2.56, 0.2.55
[INFO] [stderr] 
[INFO] [stderr] all possible versions conflict with previously selected packages.
[INFO] [stderr] 
[INFO] [stderr]   previously selected package `libc v0.2.31`
[INFO] [stderr]     ... which is depended on by `backtrace v0.3.3`
[INFO] [stderr]     ... which is depended on by `error-chain v0.12.0`
[INFO] [stderr]     ... which is depended on by `rexpect v0.3.0 (https://github.com/philippkeller/rexpect#30bfb3ed)`
[INFO] [stderr]     ... which is depended on by `shell_doctest v0.1.0 (/mnt/big/crater/work/ex/pr-63376/sources/master#60960a260f7b5c695fd0717311d72ce62dd4eb43/gh/philippkeller/shell_doctest)`
[INFO] [stderr] 
[INFO] [stderr] failed to select a version for `libc` which could resolve this conflict
[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