have a error in auger analyze

[hwdef]

➜  auger git:(master) ✗ build/auger analyze -f temp1.db
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x8 pc=0xd4efe4]
goroutine 1 [running]:
github.com/coreos/bbolt.(*Bucket).Cursor(...)
        /go/pkg/mod/github.com/coreos/bbolt@v1.3.1-coreos.3/bucket.go:84
github.com/jpbetz/auger/pkg/data.walk.func1(0xc00022c000, 0xf7ea98, 0xc00022c000)
        /go/src/github.com/jpbetz/auger/pkg/data/data.go:421 +0x84
github.com/coreos/bbolt.(*DB).View(0xc000158d20, 0xc0000e1818, 0x0, 0x0)
        /go/pkg/mod/github.com/coreos/bbolt@v1.3.1-coreos.3/db.go:698 +0x90
github.com/jpbetz/auger/pkg/data.walk(0xc000158d20, 0xc0000e18f0, 0x0, 0x0)
        /go/src/github.com/jpbetz/auger/pkg/data/data.go:419 +0x53
github.com/jpbetz/auger/pkg/data.ListKeySummaries(0x7ffedd2842bd, 0x8, 0xc0000e1a78, 0x0, 0x0, 0xc0000e1a7e, 0x0, 0x0, 0x0, 0x0, ...)
        /go/src/github.com/jpbetz/auger/pkg/data/data.go:231 +0x27b
github.com/jpbetz/auger/cmd.analyzeValidateAndRun(0x0, 0x0)
        /go/src/github.com/jpbetz/auger/cmd/analyze.go:31 +0x81
github.com/jpbetz/auger/cmd.glob..func1(0x17d1140, 0xc0001576e0, 0x0, 0x2, 0x0, 0x0)
        /go/src/github.com/jpbetz/auger/cmd/analyze.go:15 +0x22
github.com/spf13/cobra.(*Command).execute(0x17d1140, 0xc0001576c0, 0x2, 0x2, 0x17d1140, 0xc0001576c0)
        /go/pkg/mod/github.com/spf13/cobra@v0.0.1/command.go:698 +0x431
github.com/spf13/cobra.(*Command).ExecuteC(0x17d0f20, 0x37, 0xc0000e1f88, 0x4074af)
        /go/pkg/mod/github.com/spf13/cobra@v0.0.1/command.go:783 +0x2ca
github.com/spf13/cobra.(*Command).Execute(...)
        /go/pkg/mod/github.com/spf13/cobra@v0.0.1/command.go:736
main.main()
        /go/src/github.com/jpbetz/auger/main.go:26 +0x32