const golang.org/x/tools/go/packages.UnknownError

4 uses

	golang.org/x/tools/go/packages (current package)
		packages.go#L440: 	UnknownError ErrorKind = iota
		packages.go#L891: 				Kind: UnknownError, // e.g. can't find/open/parse export data
		packages.go#L937: 				Kind: UnknownError,
		packages.go#L970: 					Kind: UnknownError,