problems    []string
)

func localLinks(body string) (links []string) {
	seen := map[string]bool{}
	mv := aRx.FindAllStringSubmatch(body, -1)
	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'">]+)`)

	td, err := os.Open("testdata/src/pkg")
	if err != nil {
		t.Fatal(err)
	}
	fis, err := td.Readdir(0)
	if err != nil {
		t.Fatal(err)
	}
	for _, fi := range fis {
		if !fi.IsDir() {
			continue
		}

		// TODO(gri) remove extra pkg directory eventually
		goldenFile := filepath.Join("testdata", "src", "pkg", fi.Name(), "golden.txt")
		w := NewWalker(nil, "testdata/src/pkg")
		pkg, _ := w.import_(fi.Name())

	}
	tok = in.Stack.Next()
	if tok != '\n' {
		in.Error("unexpected token at end of #line: ", tok)
	}
	pos := src.MakePos(in.Base(), uint(in.Line())+1, 1) // +1 because #line nnn means line nnn starts on next line
	in.Stack.SetBase(src.NewLinePragmaBase(pos, file, objabi.AbsFile(objabi.WorkingDir(), file, *flags.TrimPath), uint(line), 1))
}

// #undef processing
func (in *Input) undef() {

// string to a slice of bytes.) The source and destination may overlap. Copy
// returns the number of elements copied, which will be the minimum of
// len(src) and len(dst).
func copy(dst, src []Type) int

// The delete built-in function deletes the element with the specified key
// (m[key]) from the map. If m is nil or there is no such element, delete
// is a no-op.

	"unicode"

	"cmd/asm/internal/flags"
	"cmd/internal/objabi"
	"cmd/internal/src"
)

// A Tokenizer is a simple wrapping of text/scanner.Scanner, configured
// for our purposes and made a TokenReader. It forms the lowest level,
// turning text from readers into tokens.
type Tokenizer struct {
	tok  ScanToken
	s    *scanner.Scanner
	base *src.PosBase
	line int
	file *os.File // If non-nil, file descriptor to close.
}

	// Optimal case is where the underlying reader implements io.WriterTo
	srcBuf := bytes.NewBuffer(make([]byte, 8192))
	src := NewReader(srcBuf)
	dstBuf := new(bytes.Buffer)
	dst := onlyWriter{dstBuf}
	for i := 0; i < b.N; i++ {
		srcBuf.Reset()
		src.Reset(srcBuf)
		dstBuf.Reset()
		io.Copy(dst, src)
	}
}

func BenchmarkReaderCopyUnoptimal(b *testing.B) {

package main

import (
	"fmt"
	"go/ast"
	"go/format"
	"go/parser"
	"go/scanner"
	"go/token"
	"os"
	"strings"
)

func parse(name string, src []byte, flags parser.Mode) *ast.File {
	ast1, err := parser.ParseFile(fset, name, src, flags)
	if err != nil {
		if list, ok := err.(scanner.ErrorList); ok {
			// If err is a scanner.ErrorList, its String will print just
			// the first error and then (+n more errors).

			return nil
		}

		// Otherwise, copy the bytes.
		src, err := os.Open(srcPath)
		if err != nil {
			return err
		}
		defer src.Close()

		dst, err := os.OpenFile(dstPath, os.O_WRONLY|os.O_CREATE|os.O_EXCL, perm)
		if err != nil {
			return err
		}

		_, err = io.Copy(dst, src)
		if closeErr := dst.Close(); err == nil {
			err = closeErr
		}
		return err
	})

	}
	fmt.Fprintf(p.errorWriter, format, args...)
	p.errorCount++
	if p.errorCount > 10 && !*flags.AllErrors {
		log.Fatal("too many errors")
	}
}

func (p *Parser) pos() src.XPos {
	return p.ctxt.PosTable.XPos(src.MakePos(p.lex.Base(), uint(p.lineNum), 0))
}

func (p *Parser) Parse() (*obj.Prog, bool) {
	scratch := make([][]lex.Token, 0, 3)
	for {
		word, cond, operands, ok := p.line(scratch)

	Text() string
	// File reports the source file name of the token.
	File() string
	// Base reports the position base of the token.
	Base() *src.PosBase
	// SetBase sets the position base.
	SetBase(*src.PosBase)
	// Line reports the source line number of the token.
	Line() int
	// Col reports the source column number of the token.
	Col() int
	// Close does any teardown required.
	Close()