// be extra careful: Scanner is for safe, simple jobs.
		for loop := 0; ; {
			n, err := s.r.Read(s.buf[s.end:len(s.buf)])
			if n < 0 || len(s.buf)-s.end < n {
				s.setErr(ErrBadReadCount)
				break
			}
			s.end += n
			if err != nil {
				s.setErr(err)
				break
			}
			if n > 0 {
				s.empties = 0
				break
			}
			loop++
			if loop > maxConsecutiveEmptyReads {
				s.setErr(io.ErrNoProgress)

		// Macro has arguments. Scan list of formals.
		acceptArg := true
		args = []string{} // Zero length but not nil.
	Loop:
		for {
			tok = in.Stack.Next()
			switch tok {
			case ')':
				tok = in.Stack.Next() // First token of macro definition.
				break Loop
			case ',':
				if acceptArg {
					in.Error("bad syntax in definition for macro:", name)
				}
				acceptArg = true

	case "s390x":
		return archS390x()
	case "wasm":
		return archWasm()
	}
	return nil
}

func jumpX86(word string) bool {
	return word[0] == 'J' || word == "CALL" || strings.HasPrefix(word, "LOOP") || word == "XBEGIN"
}

func jumpRISCV(word string) bool {
	switch word {
	case "BEQ", "BEQZ", "BGE", "BGEU", "BGEZ", "BGT", "BGTU", "BGTZ", "BLE", "BLEU", "BLEZ",

		p.errorf("expected identifier, found %q", p.lex.Text())
		return "", "", nil, false // Might as well stop now.
	}
	word, cond = p.lex.Text(), ""
	operands = scratch[:0]
	// Zero or more comma-separated operands, one per loop.
	nesting := 0
	colon := -1
	for tok != '\n' && tok != ';' {
		// Process one operand.
		var items []lex.Token
		if cap(operands) > len(operands) {
			// Reuse scratch items slice.

	// already have the sizes from the central directory so we can
	// just ignore these.

	return nil
}

func readDirectoryEnd(r io.ReaderAt, size int64) (dir *directoryEnd, baseOffset int64, err error) {
	// look for directoryEndSignature in the last 1k, then in the last 65k
	var buf []byte
	var directoryEndOffset int64
	for i, bLen := range []int64{1024, 65 * 1024} {
		if bLen > size {
			bLen = size
		}

	}
	return s
}

// TrimSpace returns a subslice of s by slicing off all leading and
// trailing white space, as defined by Unicode.
func TrimSpace(s []byte) []byte {
	// Fast path for ASCII: look for the first ASCII non-space byte
	start := 0
	for ; start < len(s); start++ {
		c := s[start]
		if c >= utf8.RuneSelf {
			// If we run into a non-ASCII byte, fall back to the

	{"·AddUint32(SB)", "pkg.AddUint32(SB)"},
	{"(R1, R3)", "(R1, R3)"},
	{"[R0,R1,g,R15", ""}, // Issue 11764 - asm hung parsing ']' missing register lists.
	{"[):[o-FP", ""},     // Issue 12469 - there was no infinite loop for ARM; these are just sanity checks.
	{"[):[R0-FP", ""},
	{"(", ""}, // Issue 12466 - backed up before beginning of line.
}

var ppc64OperandTests = []operandTest{
	{"$((1<<63)-1)", "$9223372036854775807"},

	case err := <-c:
		if err == nil {
			t.Error("error expected")
		} else if err != io.ErrNoProgress {
			t.Error("unexpected error:", err)
		}
	case <-time.After(time.Second):
		t.Error("test timed out (endless loop in ReadByte?)")
	}
}

// A StringReader delivers its data one string segment at a time via Read.
type StringReader struct {
	data []string
	step int
}

	// files. Internally, the tar format often uses fake "files" to add meta
	// data that describes the next file. These meta data "files" should not
	// normally be visible to the outside. As such, this loop iterates through
	// one or more "header files" until it finds a "normal file".
	format := FormatUSTAR | FormatPAX | FormatGNU
	for {
		// Discard the remainder of the file and any padding.

	// 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.
	// In cgo mode, we ignore ast2 and just apply edits directly