Does Golang run on a virtual machine?

Question

say for some very simple Golang code:

package main  import "fmt"  func plus( a int, b int) int {      return a+b }  func plusPlus(a,b,c int) int {     return a  +b  + c }  func main() {      ptr := plus     ptr2 := plusPlus      fmt.Println(ptr)     fmt.Println(ptr2) } 

This has the following output:

0x2000 0x2020 

What is going on here? This doesn't look like a function pointer, or any kind of pointer for that matter, that one would find in the stack. I also understand that Go, while offering some nice low level functionality in the threading department, also requires an OS for it to function; C is functional across all computer platforms and operating systems can be written in it while Go needs an operating system to function and in fact only works on a few OS right now. Do the very regular function pointers mean that this works on a VM? Or is the compiler just linked to low level C functions?

Answer 1

Go does not run on a virtual machine.

From the view of the language specification, ptr and ptr2 are function values. They can be called as ptr(1, 2) and ptr2(1, 2, 3).

Diving down into the implementation, the variables ptr and ptr2 are pointers to func values. See the Function Call design document for information on func values. Note the distinction between the language's "function" value and the implementation's "func" value.

Because the reflection API used by the fmt package indirects through the func values to get the pointer to print, the call tofmt.Println(ptr) prints the actual address of the plus function.