*/
package arena

import (
	"internal/reflectlite"
	"unsafe"
)

// Arena represents a collection of Go values allocated and freed together.
// Arenas are useful for improving efficiency as they may be freed back to
// the runtime manually, though any memory obtained from freed arenas must
// not be accessed once that happens. An Arena is automatically freed once
// it is no longer referenced, so it must be kept alive (see runtime.KeepAlive)

	n, err = C.sqrt(-1)
	_, err := C.voidFunc()
	var n, err = C.sqrt(1)

Calling C function pointers is currently not supported, however you can
declare Go variables which hold C function pointers and pass them
back and forth between Go and C. C code may call function pointers
received from Go. For example:

	package main

	// typedef int (*intFunc) ();
	//
	// int
	// bridge_int_func(intFunc f)
	// {

func (f *File) ParseGo(abspath string, src []byte) {
	// Two different parses: once with comments, once without.
	// The printer is not good enough at printing comments in the
	// right place when we start editing the AST behind its back,
	// so we use ast1 to look for the doc comments on import "C"
	// and on exported functions, and we use ast2 for translating
	// and reprinting.
	// In cgo mode, we ignore ast2 and just apply edits directly

	// Normal execution.
	for {
		r1, _, err := r.ReadRune()
		if err != nil {
			if err != io.EOF {
				t.Error("unexpected error on ReadRune:", err)
			}
			break
		}
		got += string(r1)
		// Put it back and read it again.
		if err = r.UnreadRune(); err != nil {
			t.Fatal("unexpected error on UnreadRune:", err)
		}
		r2, _, err := r.ReadRune()
		if err != nil {

	}
	b = b[0:n]

	// Check the resulting bytes
	if !Equal(buf.Bytes(), b) {
		t.Fatalf("incorrect result from WriteRune: %q not %q", buf.Bytes(), b)
	}

	p := make([]byte, utf8.UTFMax)
	// Read it back with ReadRune
	for r := rune(0); r < NRune; r++ {
		size := utf8.EncodeRune(p, r)
		nr, nbytes, err := buf.ReadRune()
		if nr != r || nbytes != size || err != nil {

	"unsafe"
)

// Pass a func value from nestedCall to goCallback using an integer token.
var callbackMutex sync.Mutex
var callbackToken int
var callbackFuncs = make(map[int]func())

// nestedCall calls into C, back into Go, and finally to f.
func nestedCall(f func()) {
	// callback(x) calls goCallback(x)
	callbackMutex.Lock()
	callbackToken++
	i := callbackToken
	callbackFuncs[i] = f
	callbackMutex.Unlock()

raw string literals and interpreted string literals.
</p>

<p>
Raw string literals are character sequences between back quotes, as in
<code>`foo`</code>.  Within the quotes, any character may appear except
back quote. The value of a raw string literal is the
string composed of the uninterpreted (implicitly UTF-8-encoded) characters
between the quotes;

func ARMConditionCodes(prog *obj.Prog, cond string) bool {
	if cond == "" {
		return true
	}
	bits, ok := ParseARMCondition(cond)
	if !ok {
		return false
	}
	/* hack to make B.NE etc. work: turn it into the corresponding conditional */
	if prog.As == arm.AB {
		prog.As = bcode[(bits^arm.C_SCOND_XOR)&0xf]
		bits = (bits &^ 0xf) | arm.C_SCOND_NONE
	}
	prog.Scond = bits
	return true

When Go 1.23 builds older programs, the old behaviors remain in effect.
The new [GODEBUG setting](/doc/godebug) [`asynctimerchan=1`](/pkg/time/#NewTimer)
can be used to revert back to asynchronous channel behaviors

var errDiscardedBytes = errors.New("ReadAt of discarded bytes")

func (ss *suffixSaver) ReadAt(p []byte, off int64) (n int, err error) {
	back := ss.size - off
	if back > int64(ss.keep) {
		return 0, errDiscardedBytes
	}
	suf := ss.Suffix()
	n = copy(p, suf[len(suf)-int(back):])
	if n != len(p) {
		err = io.EOF
	}
	return
}

func (ss *suffixSaver) Suffix() []byte {
	if len(ss.buf) < ss.keep {