Why is the goroutine stack infinite?

From time to time, newcomers to Go stumble upon an interesting language property related to the stack size available to the goroutine. This usually happens because the programmer inadvertently creates an infinite recursion. To illustrate this, consider the following (slightly contrived) example.

package main

import "fmt"

type S struct {
        a, b int
}

// String implements the fmt.Stringer interface
func (s *S) String() string {
        return fmt.Sprintf("%s", s) // Sprintf will call s.String()
}

func main() {
        s := &S{a: 1, b: 2}
        fmt.Println(s)
}
      
      

        
        
        
      

    
        
        
        
      
      

        
        
        
      

    
    

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