s := r.data[r.step]
		n = copy(p, s)
		r.step++
	} else {
		err = io.EOF
	}
	return
}

func readRuneSegments(t *testing.T, segments []string) {
	got := ""
	want := strings.Join(segments, "")
	r := NewReader(&StringReader{data: segments})
	for {
		r, _, err := r.ReadRune()
		if err != nil {
			if err != io.EOF {
				return
			}
			break
		}
		got += string(r)
	}

		z, err = NewReader(rat, size)
		raw = make([]byte, size)
		if _, err := rat.ReadAt(raw, 0); err != nil {
			t.Errorf("ReadAt error=%v", err)
			return
		}
	} else {
		path := filepath.Join("testdata", zt.Name)
		if zt.Obscured {
			tf, err := obscuretestdata.DecodeToTempFile(path)
			if err != nil {
				t.Errorf("obscuretestdata.DecodeToTempFile(%s): %v", path, err)
				return
			}

			continue
		}

		if want := tt.a[len(tt.a)-1] + "z"; string(x) != want {
			t.Errorf("last appended result was %s; want %s", x, want)
		}

		s := Join(a, []byte(tt.sep))
		if string(s) != tt.s {
			t.Errorf(`Join(Split(%q, %q, %d), %q) = %q`, tt.s, tt.sep, tt.n, tt.sep, s)
		}
		if tt.n < 0 {
			b := Split([]byte(tt.s), []byte(tt.sep))
			if !reflect.DeepEqual(a, b) {

					f.NoCallbacks[funcName] = true
				} else if directive == "noescape" {
					fatalf("#cgo noescape disabled until Go 1.23")
					f.NoEscapes[funcName] = true
				}
			}
		}
	}
	f.Preamble = strings.Join(linesOut, "\n")
}

// addToFlag appends args to flag.
func (p *Package) addToFlag(flag string, args []string) {
	if flag == "CFLAGS" {
		// We'll also need these when preprocessing for dwarf information.