golang: ambiguous selector when embedding structs with conflicting method names

gistfile1.go

package main                                                                     
                                                                                   
  func main() {                                                                    
>>  car{}.Model()                                                                  
  }                                                                                
                                                                                   
  type car struct {                                                                
    vehicle                                                                        
    boat                                                                           
  }                                                                                
                                                                                   
  func (c *car) dostuff() {                                                        
>>  c.Model                                                                        
  }                                                                                
                                                                                   
  type boat interface {                                                            
    Model()                                                                        
  }                                                                                
                                                                                   
  type vehicle interface {                                                         
    Model()                                                                        
  }