together. The directive can include a list of build constraints limiting its
effect to systems satisfying one of the constraints
(see https://golang.org/pkg/go/build/#hdr-Build_Constraints for details about the constraint syntax).
For example:

	// #cgo CFLAGS: -DPNG_DEBUG=1
	// #cgo amd64 386 CFLAGS: -DX86=1
	// #cgo LDFLAGS: -lpng
	// #include <png.h>
	import "C"

			case ')':
				tok = in.Stack.Next() // First token of macro definition.
				break Loop
			case ',':
				if acceptArg {
					in.Error("bad syntax in definition for macro:", name)
				}
				acceptArg = true
			case scanner.Ident:
				if !acceptArg {
					in.Error("bad syntax in definition for macro:", name)
				}
				arg := in.Stack.Text()
				if i := lookup(args, arg); i >= 0 {

					goto next
				}
			}
			if tok == scanner.EOF {
				p.errorf("unexpected EOF")
				return "", "", nil, false
			}
			// Split operands on comma. Also, the old syntax on x86 for a "register pair"
			// was AX:DX, for which the new syntax is DX, AX. Note the reordering.
			if tok == '\n' || tok == ';' || (nesting == 0 && (tok == ',' || tok == ':')) {
				if tok == ':' {

<a href="https://9p.io/sys/doc/asm.html">elsewhere</a>.
If you plan to write assembly language, you should read that document although much of it is Plan 9-specific.
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>

pkg os/exec, method (*Cmd) Environ() []string #50599
pkg os/exec, type Cmd struct, Err error #43724
pkg os/exec, var ErrDot error #43724
pkg regexp/syntax, const ErrNestingDepth = "expression nests too deeply" #51684
pkg regexp/syntax, const ErrNestingDepth ErrorCode #51684
pkg runtime/debug, func SetMemoryLimit(int64) int64 #48409
pkg sort, func Find(int, func(int) int) (int, bool) #50340

	if nameAddr.Sym.ABI() == obj.ABIInternal && flag&obj.NOSPLIT == 0 {
		p.errorf("TEXT %q: ABIInternal requires NOSPLIT", name)
	}

	// Next operand is the frame and arg size.
	// Bizarre syntax: $frameSize-argSize is two words, not subtraction.
	// Both frameSize and argSize must be simple integers; only frameSize
	// can be negative.
	// The "-argSize" may be missing; if so, set it to objabi.ArgsSizeUnknown.

pkg debug/elf, const R_PPC64_REL24_P9NOTOC R_PPC64 #60348
pkg debug/elf, method (DynFlag1) GoString() string #56887
pkg debug/elf, method (DynFlag1) String() string #56887
pkg debug/elf, method (*File) DynValue(DynTag) ([]uint64, error) #56892
pkg debug/elf, type DynFlag1 uint32 #56887
pkg encoding/binary, var NativeEndian nativeEndian #57237
pkg errors, var ErrUnsupported error #41198