if err != nil {
				t.Fatal(err)
			}
			for _, feat := range w.Features() {
				fmt.Fprintf(f, "%s\n", feat)
			}
			f.Close()
		}

		bs, err := os.ReadFile(goldenFile)
		if err != nil {
			t.Fatalf("opening golden.txt for package %q: %v", fi.Name(), err)
		}
		wanted := strings.Split(string(bs), "\n")
		sort.Strings(wanted)
		for _, feature := range wanted {
			if feature == "" {
				continue
			}

	"os"
	"path/filepath"
	"testing"
)

func FuzzReader(f *testing.F) {
	testdata, err := os.ReadDir("testdata")
	if err != nil {
		f.Fatalf("failed to read testdata directory: %s", err)
	}
	for _, de := range testdata {
		if de.IsDir() {
			continue
		}
		b, err := os.ReadFile(filepath.Join("testdata", de.Name()))
		if err != nil {
			f.Fatalf("failed to read testdata: %s", err)
		}
		f.Add(b)
	}

	// Note these errors should be independent of the architecture.
	// Just run the test with amd64.
	parser := newParser("amd64")
	var buf strings.Builder
	parser.errorWriter = &buf

	for _, cat := range testcats {
		for _, test := range cat.tests {
			parser.allowABI = cat.allowABI
			parser.errorCount = 0
			parser.lineNum++
			if !parser.pseudo(test.pseudo, tokenize(test.operands)) {

		argv := append(os.Args, "-test.run=^$")
		if err := syscall.Exec(os.Args[0], argv, os.Environ()); err != nil {
			t.Fatal(err)
		}
	}

	var cmds []*exec.Cmd
	defer func() {
		for _, cmd := range cmds {
			cmd.Process.Kill()
		}
	}()

	args := append(append([]string(nil), os.Args[1:]...), "-test.run=^Test18146$")
	for n := attempts; n > 0; n-- {
		cmd := exec.Command(os.Args[0], args...)

	RORIW	$32, X5, X6			// ERROR "immediate out of range 0 to 31"
	SLLIW	$32, X5, X6			// ERROR "immediate out of range 0 to 31"
	SRLIW	$32, X5, X6			// ERROR "immediate out of range 0 to 31"
	SRAIW	$32, X5, X6			// ERROR "immediate out of range 0 to 31"
	RORIW	$-1, X5, X6			// ERROR "immediate out of range 0 to 31"
	SLLIW	$-1, X5, X6			// ERROR "immediate out of range 0 to 31"

	// able to treat them as byte arrays, so the godefs
	// inputs in package syscall say
	//
	//	// +godefs map struct_in_addr [4]byte
	//	// +godefs map struct_in_addr6 [16]byte
	//
	for _, g := range f.Comments {
		for _, c := range g.List {
			i := strings.Index(c.Text, "+godefs map")
			if i < 0 {
				continue
			}
			s := strings.TrimSpace(c.Text[i+len("+godefs map"):])
			i = strings.Index(s, " ")
			if i < 0 {

	for _, m := range mv {
		ref := m[1]
		if strings.HasPrefix(ref, "/src/") {
			continue
		}
		if !seen[ref] {
			seen[ref] = true
			links = append(links, m[1])
		}
	}
	return
}

var idRx = regexp.MustCompile(`\bid=['"]?([^\s'">]+)`)

func pageIDs(body string) (ids []string) {
	mv := idRx.FindAllStringSubmatch(body, -1)
	for _, m := range mv {
		ids = append(ids, m[1])
	}

func TestEqualNearPageBoundary(t *testing.T) {
	t.Parallel()
	b := dangerousSlice(t)
	for i := range b {
		b[i] = 'A'
	}
	for i := 0; i <= len(b); i++ {
		Equal(b[:i], b[len(b)-i:])
		Equal(b[len(b)-i:], b[:i])
	}
}

func TestIndexByteNearPageBoundary(t *testing.T) {
	t.Parallel()
	b := dangerousSlice(t)
	for i := range b {
		idx := IndexByte(b[i:], 1)
		if idx != -1 {

	{`'\x80'`, "illegal UTF-8 encoding for character constant"},
	{"(23*4", "missing closing paren"},
	{")23*4", "unexpected ) evaluating expression"},
	{"18446744073709551616", "value out of range"},
}

func TestBadExpr(t *testing.T) {
	for i, test := range badExprTests {
		err := runBadTest(i, test, t)
		if err == nil {
			if test.error != "" {
				t.Errorf("#%d: %q: expected error %q; got none", i, test.input, test.error)
			}

	// runtime assembly code based on them.
	if objabi.LookupPkgSpecial(ctxt.Pkgpath).AllowAsmABI {
		for _, exp := range buildcfg.Experiment.Enabled() {
			flags.D = append(flags.D, "GOEXPERIMENT_"+exp)
		}
	}

	var ok, diag bool
	var failedFile string
	for _, f := range flag.Args() {
		lexer := lex.NewLexer(f)
		parser := asm.NewParser(ctxt, architecture, lexer)