if err != nil {
			return err
		}
		if i >= n {
			return errors.New("index overflow")
		}
		if capidxbit(rights.Rights[i]) != capidxbit(right) {
			return errors.New("index mismatch")
		}
		rights.Rights[i] |= right
		if capidxbit(rights.Rights[i]) != capidxbit(right) {
			return errors.New("index mismatch (after assign)")
		}
	}

	return nil
}

// other language matched.
func MatchStrings(m Matcher, lang ...string) (tag Tag, index int) {
	for _, accept := range lang {
		desired, _, err := ParseAcceptLanguage(accept)
		if err != nil {
			continue
		}
		if tag, index, conf := m.Match(desired...); conf != No {
			return tag, index
		}
	}
	tag, index, _ = m.Match()
	return
}

// Matcher is the interface that wraps the Match method.
//

)

// UnpackIndexExpr extracts data from AST nodes that represent index
// expressions.
//
// For an ast.IndexExpr, the resulting indices slice will contain exactly one
// index expression. For an ast.IndexListExpr (go1.18+), it may have a variable
// number of index expressions.
//
// For nodes that don't represent index expressions, the first return value of
// UnpackIndexExpr will be nil.

		if err != nil {
			log.Errorf("In-cluster analysis has failed: %s", err)
			return
		}
		// reorganize messages to map
		index := map[status.Resource]diag.Messages{}
		for _, m := range res.Messages {
			key := status.ResourceFromMetadata(m.Resource.Metadata)
			index[key] = append(index[key], m)
		}
		// if we previously had a message that has been removed, ensure it is removed

	}

	g := e.NewGroup()
	for index := 0; index < cfg.count; index++ {
		index := index
		workFn := func() error {
			st := time.Now()
			resp, err := doReq(ctx, cfg, index)
			if err != nil {
				fwLog.Debugf("request failed: %v", err)
				return err
			}
			fwLog.Debugf("got resp: %v", resp)

			responsesMu.Lock()
			responses[index] = resp
			responseTimes[index] = time.Since(st)

	spineLen  atomic.Uintptr            // Spine array length
	spineCap  uintptr                   // Spine array cap, accessed under spineLock

	// index is the head and tail of the spanSet in a single field.
	// The head and the tail both represent an index into the logical
	// concatenation of all blocks, with the head always behind or
	// equal to the tail (indicating an empty set). This field is
	// always accessed atomically.

	// bytes into em.
	validPS := subtle.ConstantTimeLessOrEq(2+8, index)

	valid = firstByteIsZero & secondByteIsTwo & (^lookingForIndex & 1) & validPS
	index = subtle.ConstantTimeSelect(valid, index+1, 0)
	return valid, em, index, nil
}

// nonZeroRandomBytes fills the given slice with non-zero random octets.
func nonZeroRandomBytes(s []byte, random io.Reader) (err error) {

	g := errgroup.WithNErrs(len(storageDisks))

	// Write `format.json` to all disks.
	for index := range storageDisks {
		index := index
		g.Go(func() error {
			if formats[index] == nil {
				return errDiskNotFound
			}
			return saveFormatErasure(storageDisks[index], formats[index], "")
		}, index)
	}

	// Wait for the routines to finish.

// objSym represents a symbol in an object file. It is a tuple of
// the object and the symbol's local index.
// For external symbols, objidx is the index of l.extReader (extObj),
// s is its index into the payload array.
// {0, 0} represents the nil symbol.
type objSym struct {
	objidx uint32 // index of the object (in l.objs array)
	s      uint32 // local index
}

type nameVer struct {
	name string
	v    int
}

	for i = range [5]struct{}{} {
	}
	assertequal(i, 4, " incorrect index value after range loop")

	i = 0
	var a1 [5]struct{}
	for i = range a1 {
		a1[i] = struct{}{}
	}
	assertequal(i, 4, " incorrect index value after array with zero size elem range clear")

	i = 0
	var a2 [5]int
	for i = range a2 {
		a2[i] = 0
	}
	assertequal(i, 4, " incorrect index value after array range clear")