+ If referring to a repo other than `golang/go` you can use the
  `owner/repo#issue_number` syntax: `Fixes golang/tools#1234`
+ We do not use Signed-off-by lines in Go. Please don't add them.
  Our Gerrit server & GitHub bots enforce CLA compliance instead.

See the [ZIP specification] for details.

This package does not support disk spanning.

A note about ZIP64:

To be backwards compatible the FileHeader has both 32 and 64 bit Size
fields. The 64 bit fields will always contain the correct value and
for normal archives both fields will be the same. For files requiring
the ZIP64 format the 32 bit fields will be 0xffffffff and the 64 bit
fields must be used instead.

can hold a comma-separated list of these settings.
For example, if a Go program is running in an environment that contains

	GODEBUG=http2client=0,http2server=0

then that Go program will disable the use of HTTP/2 by default in both
the HTTP client and the HTTP server.
It is also possible to set the default `GODEBUG` for a given program
(discussed below).

When preparing any change that is permitted by Go 1 compatibility

pkg math/bits (windows-amd64), const UintSize = 64
pkg math/bits, const UintSize ideal-int
pkg math/bits, func LeadingZeros(uint) int
pkg math/bits, func LeadingZeros16(uint16) int
pkg math/bits, func LeadingZeros32(uint32) int
pkg math/bits, func LeadingZeros64(uint64) int
pkg math/bits, func LeadingZeros8(uint8) int
pkg math/bits, func Len(uint) int
pkg math/bits, func Len16(uint16) int
pkg math/bits, func Len32(uint32) int

<li>
<code>R0.UXTB</code>
<br>
<code>R0.UXTB&lt;&lt;imm</code>:
<code>UXTB</code>: extract an 8-bit value from the low-order bits of <code>R0</code> and zero-extend it to the size of <code>R0</code>.
<code>R0.UXTB&lt;&lt;imm</code>: left shift the result of <code>R0.UXTB</code> by <code>imm</code> bits.
The <code>imm</code> value can be 0, 1, 2, 3, or 4.

	{"aaa", "a", 0},
	{"abc", "xyz", -1},
	{"abc", "xcz", 2},
	{"ab☺c", "x☺yz", 2},
	{"a☺b☻c☹d", "cx", len("a☺b☻")},
	{"a☺b☻c☹d", "uvw☻xyz", len("a☺b")},
	{"aRegExp*", ".(|)*+?^$[]", 7},
	{dots + dots + dots, " ", -1},
	{"012abcba210", "\xffb", 4},
	{"012\x80bcb\x80210", "\xffb", 3},
	{"0123456\xcf\x80abc", "\xcfb\x80", 10},
}

var lastIndexAnyTests = []BinOpTest{
	{"", "", -1},
	{"", "a", -1},

	if _, err := io.ReadFull(r, buf[off:12]); err != nil {
		return err
	}
	b := readBuf(buf[:12])
	if b.uint32() != f.CRC32 {
		return ErrChecksum
	}

	// The two sizes that follow here can be either 32 bits or 64 bits
	// but the spec is not very clear on this and different
	// interpretations has been made causing incompatibilities. We
	// already have the sizes from the central directory so we can
	// just ignore these.

	field[7] = ' '
}

// computeChecksum computes the checksum for the header block.
// POSIX specifies a sum of the unsigned byte values, but the Sun tar used
// signed byte values.
// We compute and return both.
func (b *block) computeChecksum() (unsigned, signed int64) {
	for i, c := range b {
		if 148 <= i && i < 156 {
			c = ' ' // Treat the checksum field itself as all spaces.
		}
		unsigned += int64(c)

		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
		}

pkg math (freebsd-riscv64-cgo), const MaxUint = 18446744073709551615 #53466
pkg math (freebsd-riscv64-cgo), const MinInt = -9223372036854775808 #53466
pkg math/bits (freebsd-riscv64), const UintSize = 64 #53466
pkg math/bits (freebsd-riscv64-cgo), const UintSize = 64 #53466
pkg os (freebsd-riscv64), const DevNull = "/dev/null" #53466
pkg os (freebsd-riscv64), const O_APPEND = 8 #53466