// which requires atomically getting an iterator and the size.
    // Moreover, we iterate this list far more often that we mutate,
    // making a (albeit home grown) copy-on-write strategy more appealing.
    private List<ProgressShieldingBuildOperationListener> listeners = Collections.emptyList();
    private final Lock listenersLock = new ReentrantLock();

pkg syscall (openbsd-386), type Dirent struct, Fileno uint32
pkg syscall (openbsd-386), type FdSet struct, Bits [32]int32
pkg syscall (openbsd-386), type Kevent_t struct, Data int32
pkg syscall (openbsd-386), type Mclpool struct, Grown uint32
pkg syscall (openbsd-386), type RtMetrics struct, Expire uint32
pkg syscall (openbsd-386), type Stat_t struct, Ino uint32
pkg syscall (openbsd-386), type Stat_t struct, Lspare0 int32

				m.close()
			} else {
				m1 = m
			}
		}
	}()

	v, headOff, head, ok := m.lookup(name)
	for !ok {
		// Lookup found an invalid pointer,
		// perhaps because the file has grown larger than the mapping.
		limit := m.load32(m.hdrLen + limitOff)
		if int64(limit) <= int64(len(m.mapping.Data)) {
			// Mapping doesn't need to grow, so lookup found actual corruption.
			debugPrintf("corrupt1\n")

func (r panicReader) Read(p []byte) (int, error) {
	if r.panic {
		panic("oops")
	}
	return 0, io.EOF
}

// Make sure that an empty Buffer remains empty when
// it is "grown" before a Read that panics
func TestReadFromPanicReader(t *testing.T) {

	// First verify non-panic behaviour
	var buf Buffer
	i, err := buf.ReadFrom(panicReader{})
	if err != nil {
		t.Fatal(err)
	}

the earth, and it would not be wonderful to meet a Megalosaurus, forty feet long or so, waddling like an elephantine lizard up Holborn Hill. Smoke lowering down from chimney-pots, making a soft black drizzle, with flakes of soot in it as big as full-grown snowflakes—gone into mourning, one might imagine, for the death of the sun. Dogs, undistinguishable in mire. Horses, scarcely better; splashed to their very blinkers. Foot passengers, jostling one another’s umbrellas in a general infection of ill temper,...

		return 8, nil
	case []float32:
		return 4 * len(data), nil
	case []float64:
		return 8 * len(data), nil
	}
	return 0, nil
}

// ensure grows buf to length len(buf) + n and returns the grown buffer
// and a slice starting at the original length of buf (that is, buf2[len(buf):]).
func ensure(buf []byte, n int) (buf2, pos []byte) {
	l := len(buf)
	buf = slices.Grow(buf, n)[:l+n]
	return buf, buf[l:]

	sc.value.Store(ssc.pack())
}

// scavChunkData tracks information about a palloc chunk for
// scavenging. It packs well into 64 bits.
//
// The zero value always represents a valid newly-grown chunk.
type scavChunkData struct {
	// inUse indicates how many pages in this chunk are currently
	// allocated.
	//
	// Only the first 10 bits are used.
	inUse uint16

// osPreemptExtEnter is called before entering external code that may
// call ExitProcess.
//
// This must be nosplit because it may be called from a syscall with
// untyped stack slots, so the stack must not be grown or scanned.
//
//go:nosplit
func osPreemptExtEnter(mp *m) {
	for !atomic.Cas(&mp.preemptExtLock, 0, 1) {
		// An asynchronous preemption is in progress. It's not

	if b := (offAddr{base}); b.lessThan(p.searchAddr) {
		p.searchAddr = b
	}

	// Add entries into chunks, which is sparse, if needed. Then,
	// initialize the bitmap.
	//
	// Newly-grown memory is always considered scavenged.
	// Set all the bits in the scavenged bitmaps high.
	for c := chunkIndex(base); c < chunkIndex(limit); c++ {
		if p.chunks[c.l1()] == nil {
			// Create the necessary l2 entry.

func timeSleepUntil() int64 {
	next := int64(maxWhen)

	// Prevent allp slice changes. This is like retake.
	lock(&allpLock)
	for _, pp := range allp {
		if pp == nil {
			// This can happen if procresize has grown
			// allp but not yet created new Ps.
			continue
		}

		if w := pp.timers.wakeTime(); w != 0 {
			next = min(next, w)
		}
	}
	unlock(&allpLock)

	return next
}