garble build
exec ./main
cmp stderr main.stderr
binsubstr main$exe 'privateAdd'

[short] stop # no need to verify this with -short

go build
exec ./main
cmp stderr main.stderr

-- go.mod --
module test/main
-- main.go --
package main

/*
static int privateAdd(int a, int b) {
	return a + b;
}
*/
import "C"

func main() {
	println(C.privateAdd(C.int(1), C.int(2)))
}
-- main.stderr --
3