must be placed in preambles in other files, or in C source files.

# Passing pointers

Go is a garbage collected language, and the garbage collector needs to
know the location of every pointer to Go memory. Because of this,
there are restrictions on passing pointers between Go and C.

In this section the term Go pointer means a pointer to memory

The memory model is specified more formally in the next section.
</p>

<p>
A data race is defined as
a write to a memory location happening concurrently with another read or write to that same location,
unless all the accesses involved are atomic data accesses as provided by the <code>sync/atomic</code> package.
As noted already, programmers are strongly encouraged to use appropriate synchronization

dependencies.
</p>

<p>
The grammar is compact and simple to parse, allowing for easy analysis
by automatic tools such as integrated development environments.
</p>

<h2 id="Notation">Notation</h2>
<p>
The syntax is specified using Extended Backus-Naur Form (EBNF):
</p>

<pre class="grammar">
Production  = production_name "=" [ Expression ] "." .
Expression  = Alternative { "|" Alternative } .

			yBytes := Repeat(y, growLen)
			allocs := testing.AllocsPerRun(100, func() {
				buf.Grow(growLen)
				buf.Write(yBytes)
			})
			// Check no allocation occurs in write, as long as we're single-threaded.
			if allocs != 0 {
				t.Errorf("allocation occurred during write")
			}
			// Check that buffer has correct data.
			if !Equal(buf.Bytes()[0:startLen-readBytes], xBytes[readBytes:]) {

	}
}

func TestCVE202139293(t *testing.T) {
	// directory size is so large, that the check in Reader.init
	// overflows when subtracting from the archive size, causing
	// the pre-allocation check to be bypassed.
	data := []byte{
		0x50, 0x4b, 0x06, 0x06, 0x05, 0x06, 0x31, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x50, 0x4b,
		0x06, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01,

## Tools {#tools}

### Go command {#go-command}

Setting the `GOROOT_FINAL` environment variable no longer has an effect
([#62047](https://go.dev/issue/62047)).
Distributions that install the `go` command to a location other than
`$GOROOT/bin/go` should install a symlink instead of relocating
or copying the `go` binary.

### Vet {#vet}

The `go vet` subcommand now includes the

</p>

<p>
The syntax is compact and simple to parse, allowing for easy analysis
by automatic tools such as integrated development environments.
</p>

<h2 id="Notation">Notation</h2>
<p>
The syntax is specified using a
<a href="https://en.wikipedia.org/wiki/Wirth_syntax_notation">variant</a>
of Extended Backus-Naur Form (EBNF):
</p>

<pre class="grammar">
Syntax      = { Production } .

			rp.n++
		}
	}
	return len(p), nil
}

func memset(a []byte, b byte) {
	if len(a) == 0 {
		return
	}
	// Double, until we reach power of 2 >= len(a), same as bytes.Repeat,
	// but without allocation.
	a[0] = b
	for i, l := 1, len(a); i < l; i *= 2 {
		copy(a[i:], a[:i])
	}
}

func (r *rleBuffer) ReadAt(p []byte, off int64) (n int, err error) {
	if len(p) == 0 {
		return
	}

		b.uint64(size)                   // size of the central directory
		b.uint64(offset)                 // offset of start of central directory with respect to the starting disk number

		// zip64 end of central directory locator
		b.uint32(directory64LocSignature)
		b.uint32(0)           // number of the disk with the start of the zip64 end of central directory
		b.uint64(uint64(end)) // relative offset of the zip64 end of central directory record

	ORN	X6, X7					// b3e36340
	SEXTB	X16, X17				// 93184860
	SEXTH	X17, X18				// 13995860
	XNOR	X18, X19, X20				// 33ca2941
	XNOR	X18, X19				// b3c92941
	ZEXTH	X19, X20				// 3bca0908

	// 1.3: Bitwise Rotation (Zbb)
	ROL	X8, X9, X10				// 33958460 or b30f8040b3dff4013395840033e5af00
	ROL	X8, X9					// b3948460 or b30f8040b3dff401b3948400b3e49f00
	ROLW	X9, X10, X11				// bb159560 or b30f9040bb5ff501bb159500b3e5bf00