}

	*(*slice)(unsafe.Pointer(&b)) = slice{p, size, int(mem / 4)}
	return
}

// used by cmd/cgo
func gobytes(p *byte, n int) (b []byte) {
	if n == 0 {
		return make([]byte, 0)
	}

	if n < 0 || uintptr(n) > maxAlloc {
		panic(errorString("gobytes: length out of range"))
	}

	bp := mallocgc(uintptr(n), nil, false)
	memmove(bp, unsafe.Pointer(p), uintptr(n))

	Name      string
	Got, Want interface{}
}

var testPairs = []testPair{
	{"GoString", C.GoString(C.greeting), greeting},
	{"GoStringN", C.GoStringN(C.greeting, 5), greeting[:5]},
	{"GoBytes", C.GoBytes(unsafe.Pointer(C.greeting), 5), []byte(greeting[:5])},
}

func testHelpers(t *testing.T) {
	for _, pair := range testPairs {
		if !reflect.DeepEqual(pair.Got, pair.Want) {

	// C string to Go string
	func C.GoString(*C.char) string

	// C data with explicit length to Go string
	func C.GoStringN(*C.char, C.int) string

	// C data with explicit length to Go []byte
	func C.GoBytes(unsafe.Pointer, C.int) []byte

As a special case, C.malloc does not call the C library malloc directly
but instead calls a Go helper function that wraps the C library malloc