The frame size <code>$24-8</code> states that the function has a 24-byte frame
and is called with 8 bytes of argument, which live on the caller's frame.
If <code>NOSPLIT</code> is not specified for the <code>TEXT</code>,
the argument size must be provided.
For assembly functions with Go prototypes, <code>go</code> <code>vet</code> will check that the
argument size is correct.
</p>

<p>

		} __attribute__((__packed__, __gcc_struct__)) *a = v;
		a->r = puts((void*)a->p0);
	}

It extracts the arguments from the pointer to _Cfunc_puts's argument
frame, invokes the system C function (in this case, puts), stores the
result in the frame, and returns.

Linking

Once the _cgo_export.c and *.cgo2.c files have been compiled with gcc,
they need to be linked into the final binary, along with the libraries

		"test.TestCallbackCallers",
		"testing.tRunner",
		"runtime.goexit",
	}
	nestedCall(func() {
		n = runtime.Callers(4, pc)
	})
	if n != len(name) {
		t.Errorf("expected %d frames, got %d", len(name), n)
	}
	for i := 0; i < n; i++ {
		f := runtime.FuncForPC(pc[i] - 1) // TODO: use runtime.CallersFrames
		if f == nil {
			t.Fatalf("expected non-nil Func for pc %d", pc[i])
		}

		t.Skip("skipping for non-gc toolchain")
	}
	if runtime.GOARCH != "amd64" {
		// TODO: support SEH on other architectures.
		t.Skip("skipping on non-amd64")
	}
	// Only frames in the test package are checked.
	want := []string{
		"test._Cfunc_backtrace",
		"test.testCallbackCallersSEH.func1.1",
		"test.testCallbackCallersSEH.func1",
		"test.goCallback",
		"test._Cfunc_callback",

	op := operands[next]
	if len(op) < 2 || op[0].ScanToken != '$' {
		p.errorf("TEXT %s: frame size must be an immediate constant", name)
		return
	}
	op = op[1:]
	negative := false
	if op[0].ScanToken == '-' {
		negative = true
		op = op[1:]
	}
	if len(op) == 0 || op[0].ScanToken != scanner.Int {
		p.errorf("TEXT %s: frame size must be an immediate constant", name)
		return
	}