pkg syscall (darwin-arm64), const CS7 ideal-int
pkg syscall (darwin-arm64), const CS8 = 768
pkg syscall (darwin-arm64), const CS8 ideal-int
pkg syscall (darwin-arm64), const CSIZE = 768
pkg syscall (darwin-arm64), const CSIZE ideal-int
pkg syscall (darwin-arm64), const CSTART = 17
pkg syscall (darwin-arm64), const CSTART ideal-int
pkg syscall (darwin-arm64), const CSTATUS = 20

pkg syscall (freebsd-arm64), const CS7 ideal-int
pkg syscall (freebsd-arm64), const CS8 = 768
pkg syscall (freebsd-arm64), const CS8 ideal-int
pkg syscall (freebsd-arm64), const CSIZE = 768
pkg syscall (freebsd-arm64), const CSIZE ideal-int
pkg syscall (freebsd-arm64), const CSTART = 17
pkg syscall (freebsd-arm64), const CSTART ideal-int
pkg syscall (freebsd-arm64), const CSTATUS = 20

)

const (
	// MaxScanTokenSize is the maximum size used to buffer a token
	// unless the user provides an explicit buffer with [Scanner.Buffer].
	// The actual maximum token size may be smaller as the buffer
	// may need to include, for instance, a newline.
	MaxScanTokenSize = 64 * 1024

	startBufSize = 4096 // Size of initial allocation for buffer.
)

func NewReader(r io.ReaderAt, size int64) (*Reader, error) {
	if size < 0 {
		return nil, errors.New("zip: size cannot be negative")
	}
	zr := new(Reader)
	var err error
	if err = zr.init(r, size); err != nil && err != ErrInsecurePath {
		return nil, err
	}
	return zr, err
}

func (r *Reader) init(rdr io.ReaderAt, size int64) error {
	end, baseOffset, err := readDirectoryEnd(rdr, size)

	directoryEndLen          = 22         // + comment
	dataDescriptorLen        = 16         // four uint32: descriptor signature, crc32, compressed size, size
	dataDescriptor64Len      = 24         // two uint32: signature, crc32 | two uint64: compressed size, size
	directory64LocLen        = 20         //
	directory64EndLen        = 56         // + extra

	// Constants for the first byte in CreatorVersion.
	creatorFAT    = 0

	SOURCE="$(readlink "$SOURCE")"
	[[ $SOURCE != /* ]] && SOURCE="$DIR/$SOURCE"
done
DIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"

# Increase the V8 stack size from the default of 984K
# to 8192K to ensure all tests can pass without hitting
# stack size limits.

pkg archive/tar, type FileInfoNames interface { Gname, IsDir, ModTime, Mode, Name, Size, Sys, Uname } #50102
pkg archive/tar, type FileInfoNames interface, Gname() (string, error) #50102
pkg archive/tar, type FileInfoNames interface, IsDir() bool #50102
pkg archive/tar, type FileInfoNames interface, ModTime() time.Time #50102
pkg archive/tar, type FileInfoNames interface, Mode() fs.FileMode #50102
pkg archive/tar, type FileInfoNames interface, Name() string #50102

After the symbol, the arguments are flags (see below)
and the frame size, a constant (but see below):
</p>

<pre>
TEXT runtime·profileloop(SB),NOSPLIT,$8
	MOVQ	$runtime·profileloop1(SB), CX
	MOVQ	CX, 0(SP)
	CALL	runtime·externalthreadhandler(SB)
	RET
</pre>

<p>
In the general case, the frame size is followed by an argument size, separated by a minus sign.
(It's not a subtraction, just idiosyncratic syntax.)

const (
	magicGNU, versionGNU     = "ustar ", " \x00"
	magicUSTAR, versionUSTAR = "ustar\x00", "00"
	trailerSTAR              = "tar\x00"
)

// Size constants from various tar specifications.
const (
	blockSize  = 512 // Size of each block in a tar stream
	nameSize   = 100 // Max length of the name field in USTAR format
	prefixSize = 155 // Max length of the prefix field in USTAR format

}

func TestEqualExhaustive(t *testing.T) {
	var size = 128
	if testing.Short() {
		size = 32
	}
	a := make([]byte, size)
	b := make([]byte, size)
	b_init := make([]byte, size)
	// randomish but deterministic data
	for i := 0; i < size; i++ {
		a[i] = byte(17 * i)
		b_init[i] = byte(23*i + 100)
	}

	for len := 0; len <= size; len++ {
		for x := 0; x <= size-len; x++ {
			for y := 0; y <= size-len; y++ {