for n := attempts; n > 0; n-- {
		cmd := exec.Command(os.Args[0], args...)
		cmd.Env = append(os.Environ(), "test18146=exec")
		buf := bytes.NewBuffer(nil)
		cmd.Stdout = buf
		cmd.Stderr = buf
		if err := cmd.Start(); err != nil {
			// We are starting so many processes that on
			// some systems (problem seen on Darwin,
			// Dragonfly, OpenBSD) the fork call will fail
			// with EAGAIN.
			if pe, ok := err.(*os.PathError); ok {

_cgo_import.go, which looks like:

	//go:cgo_dynamic_linker "/lib64/ld-linux-x86-64.so.2"
	//go:cgo_import_dynamic puts puts#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic __libc_start_main __libc_start_main#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic stdout stdout#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic fflush fflush#GLIBC_2.2.5 "libc.so.6"
	//go:cgo_import_dynamic _ _ "libpthread.so.0"

		if s.err != nil {
			// Shut it down.
			s.start = 0
			s.end = 0
			return false
		}
		// Must read more data.
		// First, shift data to beginning of buffer if there's lots of empty space
		// or space is needed.
		if s.start > 0 && (s.end == len(s.buf) || s.start > len(s.buf)/2) {
			copy(s.buf, s.buf[s.start:s.end])
			s.end -= s.start
			s.start = 0
		}
		// Is the buffer full? If so, resize.

		}
	}()

	parse()

	return nil
}

func testBadOperandParser(t *testing.T, parser *Parser, tests []badOperandTest) {
	for _, test := range tests {
		err := tryParse(t, func() {
			parser.start(lex.Tokenize(test.input))
			addr := obj.Addr{}
			parser.operand(&addr)
		})

		switch {
		case err == nil:
			t.Errorf("fail at %s: got no errors; expected %s\n", test.input, test.error)

	// more efficient, possibly due to cache effects.
	start := -1 // valid span start if >= 0
	for i := 0; i < len(s); {
		size := 1
		r := rune(s[i])
		if r >= utf8.RuneSelf {
			r, size = utf8.DecodeRune(s[i:])
		}
		if f(r) {
			if start >= 0 {
				spans = append(spans, span{start, i})
				start = -1
			}
		} else {
			if start < 0 {
				start = i
			}
		}
		i += size
	}

// printed.
func (f *File) ParseGo(abspath string, src []byte) {
	// Two different parses: once with comments, once without.
	// The printer is not good enough at printing comments in the
	// right place when we start editing the AST behind its back,
	// so we use ast1 to look for the doc comments on import "C"
	// and on exported functions, and we use ast2 for translating
	// and reprinting.

		t.Errorf("%v: OpenRaw error=%v", f.Name, err)
		return
	}
	start, err := f.DataOffset()
	if err != nil {
		t.Errorf("%v: DataOffset error=%v", f.Name, err)
		return
	}
	got, err := io.ReadAll(rw)
	if err != nil {
		t.Errorf("%v: OpenRaw ReadAll error=%v", f.Name, err)
		return
	}
	end := uint64(start) + f.CompressedSize64
	want := raw[start:end]
	if !bytes.Equal(got, want) {
		t.Logf("got %q", got)

	{"4611686018427387904", 4611686018427387904, true},
}

func TestExpr(t *testing.T) {
	p := NewParser(nil, nil, nil) // Expression evaluation uses none of these fields of the parser.
	for i, test := range exprTests {
		p.start(lex.Tokenize(test.input))
		result := int64(p.expr())
		if result != test.output {
			t.Errorf("%d: %q evaluated to %d; expected %d", i, test.input, result, test.output)
		}
		tok := p.next()

pkg syscall (linux-386), type Flock_t struct
pkg syscall (linux-386), type Flock_t struct, Len int64
pkg syscall (linux-386), type Flock_t struct, Pid int32
pkg syscall (linux-386), type Flock_t struct, Start int64
pkg syscall (linux-386), type Flock_t struct, Type int16
pkg syscall (linux-386), type Flock_t struct, Whence int16
pkg syscall (linux-386-cgo), func FcntlFlock(uintptr, int, *Flock_t) error

	b := []byte{0, 1, 2, 3, 4}
	tmp := make([]byte, 5)
	for i := 0; i <= 5; i++ {
		for j := i; j <= 5; j++ {
			for k := 0; k <= 6; k++ {
				// 0 <= i <= j <= 5; 0 <= k <= 6
				// Check that if we start with a buffer
				// of length j at offset i and ask for
				// Next(k), we get the right bytes.
				buf := NewBuffer(b[0:j])
				n, _ := buf.Read(tmp[0:i])
				if n != i {
					t.Fatalf("Read %d returned %d", i, n)