The current document provides a summary of the syntax and the differences with
what is explained in that document, and
describes the peculiarities that apply when writing assembly code to interact with Go.
</p>

<p>
The most important thing to know about Go's assembler is that it is not a direct representation of the underlying machine.
Some of the details map precisely to the machine, but some do not.
This is because the compiler suite (see

func (rc *ReadCloser) Close() error {
	return rc.f.Close()
}

// DataOffset returns the offset of the file's possibly-compressed
// data, relative to the beginning of the zip file.
//
// Most callers should instead use [File.Open], which transparently
// decompresses data and verifies checksums.
func (f *File) DataOffset() (offset int64, err error) {
	bodyOffset, err := f.findBodyOffset()
	if err != nil {

controlled by the [`execerrdot` setting](/pkg/os/exec#hdr-Executables_in_the_current_directory).
There is no plan to remove this setting.

### Go 1.18

Go 1.18 removed support for SHA1 in most X.509 certificates,
controlled by the [`x509sha1` setting](/pkg/crypto/x509#InsecureAlgorithmError).
This setting will be removed in a future release, Go 1.22 at the earliest.

### Go 1.10

pkg syscall (freebsd-riscv64), const DLT_MFR = 182 #53466
pkg syscall (freebsd-riscv64), const DLT_MFR ideal-int #53466
pkg syscall (freebsd-riscv64), const DLT_MOST = 211 #53466
pkg syscall (freebsd-riscv64), const DLT_MOST ideal-int #53466
pkg syscall (freebsd-riscv64), const DLT_MPEG_2_TS = 243 #53466
pkg syscall (freebsd-riscv64), const DLT_MPEG_2_TS ideal-int #53466

// the subslices between those separators.
// If sep is empty, SplitN splits after each UTF-8 sequence.
// The count determines the number of subslices to return:
//
//	n > 0: at most n subslices; the last subslice will be the unsplit remainder.
//	n == 0: the result is nil (zero subslices)
//	n < 0: all subslices
//
// To split around the first instance of a separator, see Cut.

pkg syscall (darwin-386), const INPCK ideal-int
pkg syscall (darwin-386), const IN_CLASSA_HOST = 16777215
pkg syscall (darwin-386), const IN_CLASSA_MAX = 128
pkg syscall (darwin-386), const IN_CLASSA_NET = 4278190080
pkg syscall (darwin-386), const IN_CLASSA_NSHIFT = 24
pkg syscall (darwin-386), const IN_CLASSB_HOST = 65535
pkg syscall (darwin-386), const IN_CLASSB_MAX = 65536

	}
	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()))...)
}

// enabled reports whether the input is enabled by an ifdef, or is at the top level.

<p>
A "for" statement with a ForClause is also controlled by its condition, but
additionally it may specify an <i>init</i>
and a <i>post</i> statement, such as an assignment,
an increment or decrement statement. The init statement may be a
<a href="#Short_variable_declarations">short variable declaration</a>, but the post statement must not.
</p>

<pre class="ebnf">
ForClause = [ InitStmt ] ";" [ Condition ] ";" [ PostStmt ] .

	toPatch       []Patch
	addr          []obj.Addr
	arch          *arch.Arch
	ctxt          *obj.Link
	firstProg     *obj.Prog
	lastProg      *obj.Prog
	dataAddr      map[string]int64 // Most recent address for DATA for this symbol.
	isJump        bool             // Instruction being assembled is a jump.
	allowABI      bool             // Whether ABI selectors are allowed.

		}
		b.fill() // buffer is empty
	}
	c := b.buf[b.r]
	b.r++
	b.lastByte = int(c)
	return c, nil
}

// UnreadByte unreads the last byte. Only the most recently read byte can be unread.
//
// UnreadByte returns an error if the most recent method called on the
// [Reader] was not a read operation. Notably, [Reader.Peek], [Reader.Discard], and [Reader.WriteTo] are not
// considered read operations.