It should be panic here

[johnnyluo586]

➜ git:(master) ✗ dep ensure -update github.com/Sirupsen/logrus
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x50 pc=0x133dfcc]

goroutine 58 [running]:
github.com/golang/dep/vendor/github.com/sdboyer/gps.(*SourceMgr).SyncSourceFor(0xc42009ee40, 0xc420171a20, 0x10, 0x0, 0x0, 0x0, 0x0)
/go/src/github.com/golang/dep/vendor/github.com/sdboyer/gps/source_manager.go:461 +0x10c
github.com/golang/dep/vendor/github.com/sdboyer/gps.(*bridge).breakLock.func1(0xc4201cffc0, 0xc420171a20, 0x10, 0x0, 0x0, 0x1607180, 0xc42024e640)
/go/src/github.com/golang/dep/vendor/github.com/sdboyer/gps/bridge.go:341 +0x68
created by github.com/golang/dep/vendor/github.com/sdboyer/gps.(*bridge).breakLock
/go/src/github.com/golang/dep/vendor/github.com/sdboyer/gps/bridge.go:345 +0x240

[sdboyer]

Thanks for the bug report - closing this as dupe of #250