specified by a -I flag), then "#include <foo/bar.h>" will always find the
local version in preference to any other version.

The cgo tool is enabled by default for native builds on systems where
it is expected to work. It is disabled by default when cross-compiling
as well as when the CC environment variable is unset and the default
C compiler (typically gcc or clang) cannot be found on the system PATH.

//	sparse files      |     no |       yes |       yes
//
// The table's upper portion shows the [Header] fields, where each format reports
// the maximum number of bytes allowed for each string field and
// the integer type used to store each numeric field
// (where timestamps are stored as the number of seconds since the Unix epoch).
//
// The table's lower portion shows specialized features of each format,

func (b *Buffer) Reset() {
	b.buf = b.buf[:0]
	b.off = 0
	b.lastRead = opInvalid
}

// tryGrowByReslice is an inlineable version of grow for the fast-case where the
// internal buffer only needs to be resliced.
// It returns the index where bytes should be written and whether it succeeded.
func (b *Buffer) tryGrowByReslice(n int) (int, bool) {
	if l := len(b.buf); n <= cap(b.buf)-l {
		b.buf = b.buf[:l+n]

	Xattrs map[string]string

	// PAXRecords is a map of PAX extended header records.
	//
	// User-defined records should have keys of the following form:
	//	VENDOR.keyword
	// Where VENDOR is some namespace in all uppercase, and keyword may
	// not contain the '=' character (e.g., "GOLANG.pkg.version").
	// The key and value should be non-empty UTF-8 strings.
	//

	}
	fmt.Fprintf(os.Stderr, "%s:%d: %s", in.File(), in.Line(), fmt.Sprintln(args...))
	os.Exit(1)
}

// expectText is like Error but adds "got XXX" where XXX is a quoted representation of the most recent token.
func (in *Input) expectText(args ...interface{}) {
	in.Error(append(args, "; got", strconv.Quote(in.Stack.Text()))...)
}

Thus <code>-2</code> is not the integer value minus two,
but the unsigned 64-bit integer with the same bit pattern.
The distinction rarely matters but
to avoid ambiguity, division or right shift where the right operand's
high bit is set is rejected.
</p>

<h3 id="symbols">Symbols</h3>

<p>
Some symbols, such as <code>R1</code> or <code>LR</code>,
are predefined and refer to registers.

		// resulting in a file with compressed size > 0 but uncompressed size ==
		// 0. We still want to fail when a directory has associated uncompressed
		// data, but we are tolerant of cases where the uncompressed size is
		// zero but compressed size is not.
		if f.UncompressedSize64 != 0 {
			return &dirReader{ErrFormat}, nil
		} else {
			return &dirReader{io.EOF}, nil
		}
	}

	//	$sym±offset(SB)(reg)(index*scale)
	// Exceptions are:
	//
	//	R1
	//	offset
	//	$offset
	// Every piece is optional, so we scan left to right and what
	// we discover tells us where we are.

	// Prefix: $.
	var prefix rune
	switch tok := p.peek(); tok {
	case '$', '*':
		prefix = rune(tok)
		p.next()
	}

	// Symbol: sym±offset(SB)
	tok := p.next()

	// should therefore be always resident in the L1 cache - until we
	// have completed the construction of the result.
	// This yields significant speedups (up to +100%) in cases where
	// the result length is large (roughly, over L2 cache size).
	const chunkLimit = 8 * 1024
	chunkMax := n
	if chunkMax > chunkLimit {
		chunkMax = chunkLimit / len(b) * len(b)
		if chunkMax == 0 {

	"io/fs"
	"math"
	"os"
	"path"
	"path/filepath"
	"reflect"
	"strings"
	"testing"
	"time"
)

type testError struct{ error }

type fileOps []any // []T where T is (string | int64)

// testFile is an io.ReadWriteSeeker where the IO operations performed
// on it must match the list of operations in ops.
type testFile struct {
	ops fileOps
	pos int64
}

func (f *testFile) Read(b []byte) (int, error) {