cgo - 'runtime.h' file not found in MacOSX

Question

I am trying to execute the cgo program as mentioned here

    package main

    /*
    #include "runtime.h"

    int goId() {
            return g->goid;
    }
    */
    import "C"
    import "fmt"

    func main() {
     x := C.goId()
     fmt.Printf("Id - %d", x)
    }

On running the above program I am getting the below error:-

jab-MacBook-Pro-4:src debraj$ go build gid.go
# command-line-arguments
./gid.go:4:10: fatal error: 'runtime.h' file not found
#include "runtime.h"
         ^
1 error generated.

If I change the header to be like below:-

#include <objc/runtime.h>

then it is giving me the below error:-

jab-MacBook-Pro-4:src debraj$ go build gid.go
# command-line-arguments
./gid.go:7:9: error: use of undeclared identifier 'g'
        return g->goid;
               ^
1 error generated.

Environment

• MacOSX - 10.11.6
• Go - 1.7.3

Can someone let me know how can I run the above program in MacOSX?

Answer 1

As discussed in golang-nuts this is not possible as of Go 1.5

That's not a cgo program there, but a Go program, which uses the gc compiler's affinity to compile C programs into the resulting binary.

But since Go 1.5.0, that C backend is removed (the last version is 1.4.2), so that side effect has vanished.