fs, err := os.ReadDir(fmt.Sprintf("/proc/%d/task", pid))
	if err != nil {
		return fmt.Errorf("unable to find %d tasks: %v", pid, err)
	}
	expectedProc := fmt.Sprintf("Pid:\t%d", pid)
	foundAThread := false
	for _, f := range fs {
		tf := fmt.Sprintf("/proc/%s/status", f.Name())
		d, err := os.ReadFile(tf)
		if err != nil {
			// There are a surprising number of ways this
			// can error out on linux.  We've seen all of

func isASCII(s string) bool {
	for _, c := range s {
		if c >= 0x80 || c == 0x00 {
			return false
		}
	}
	return true
}

// toASCII converts the input to an ASCII C-style string.
// This is a best effort conversion, so invalid characters are dropped.
func toASCII(s string) string {
	if isASCII(s) {
		return s
	}
	b := make([]byte, 0, len(s))
	for _, c := range s {
		if c < 0x80 && c != 0x00 {

	if err != nil {
		if os.IsNotExist(err) {
			t.Skip("no /proc/self/exe")
		}
		t.Fatal("opening /proc/self/exe: ", err)
	}
	defer f.Close()

	c := 0
sections:
	for i, s := range f.Sections {
		if s.Type != elf.SHT_NOTE {
			continue
		}

		d, err := s.Data()
		if err != nil {
			t.Logf("reading data of note section %d: %v", i, err)
			continue
		}

		for len(d) > 0 {

		// If we were unable to read anything out of the archive don't
		// bother trying to roundtrip it.
		if len(files) == 0 {
			return
		}

		out := bytes.NewBuffer(nil)
		w := NewWriter(out)
		for _, f := range files {
			if err := w.WriteHeader(f.header); err != nil {
				t.Fatalf("unable to write previously parsed header: %s", err)
			}
			if _, err := w.Write(f.content); err != nil {

	cond = strings.TrimPrefix(cond, ".")
	if cond == "" {
		return arm.C_SCOND_NONE, true
	}
	names := strings.Split(cond, ".")
	bits := uint8(0)
	for _, name := range names {
		if b, present := ls[name]; present {
			bits |= b
			continue
		}
		if b, present := scond[name]; present {
			bits = (bits &^ arm.C_SCOND) | b
			continue
		}
		return 0, false
	}

func (b *Buffer) Truncate(n int) {
	if n == 0 {
		b.Reset()
		return
	}
	b.lastRead = opInvalid
	if n < 0 || n > b.Len() {
		panic("bytes.Buffer: truncation out of range")
	}
	b.buf = b.buf[:b.off+n]
}

// Reset resets the buffer to be empty,
// but it retains the underlying storage for use by future writes.
// Reset is the same as [Buffer.Truncate](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])
	}

	}

	instructions := make(map[string]obj.As)
	for i, s := range obj.Anames {
		instructions[s] = obj.As(i)
	}
	for i, s := range ppc64.Anames {
		if obj.As(i) >= obj.A_ARCHSPECIFIC {
			instructions[s] = obj.As(i) + obj.ABasePPC64
		}
	}
	// The opcodes generated by x/arch's ppc64map are listed in
	// a separate slice, add them too.
	for i, s := range ppc64.GenAnames {
		instructions[s] = obj.As(i) + ppc64.AFIRSTGEN

	for i := 0; i <= 2*maxWnd; i++ {
		for _, window := range windows {
			if window > len(b[i:]) {
				window = len(b[i:])
			}
			testCountWindow(i, window)
			for j := 0; j < window; j++ {
				b[i+j] = byte(0)
			}
		}
	}
	for i := 4096 - (maxWnd + 1); i < len(b); i++ {
		for _, window := range windows {
			if window > len(b[i:]) {
				window = len(b[i:])
			}

	{`'\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)
			}