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")

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:]

	heapArenaAlloc linearAlloc

	// arenaHints is a list of addresses at which to attempt to
	// add more heap arenas. This is initially populated with a
	// set of general hint addresses, and grown with the bounds of
	// actual heap arena ranges.
	arenaHints *arenaHint

	// arena is a pre-reserved space for allocating heap arenas
	// (the actual arenas). This is only used on 32-bit.
	arena linearAlloc

	if debug.gccheckmark > 0 {
		// This is expensive when there's a large number of
		// Gs, so only do it if checkmark is also enabled.
		gcMarkRootCheck()
	}

	// Drop allg snapshot. allgs may have grown, in which case
	// this is the only reference to the old backing store and
	// there's no need to keep it around.
	work.stackRoots = nil

	// Clear out buffers and double-check that all gcWork caches

			it.key = k
			if t.IndirectElem() {
				e = *((*unsafe.Pointer)(e))
			}
			it.elem = e
		} else {
			// The hash table has grown since the iterator was started.
			// The golden data for this key is now somewhere else.
			// Check the current hash table for the data.
			// This code handles the case where the key

     * cause a concurrent read operation to see inconsistent data. This is made easier by the
     * nature of the read operations in Map. For example, no operation can reveal that the table
     * has grown but the threshold has not yet been updated, so there are no atomicity requirements
     * for this with respect to reads.
     *
     * As a guide, all critical volatile reads and writes to the count field are marked in code

		// have other uintptr-typed stack references as well.
		// If during one of the calls that got us here or during one of the
		// callbacks below the stack must be grown, all these uintptr references
		// to the stack will not be updated, and traceback will continue
		// to inspect the old stack memory, which may no longer be valid.

     * cause a concurrent read operation to see inconsistent data. This is made easier by the
     * nature of the read operations in Map. For example, no operation can reveal that the table
     * has grown but the threshold has not yet been updated, so there are no atomicity requirements
     * for this with respect to reads.
     *
     * As a guide, all critical volatile reads and writes to the count field are marked in code

     * concurrent read operation to see inconsistent data. This is made easier by the nature of the
     * read operations in Map. For example, no operation can reveal that the table has grown but the
     * threshold has not yet been updated, so there are no atomicity requirements for this with
     * respect to reads.
     *