val    any     // type as a value
		_32bit uintptr // size on 32bit platforms
		_64bit uintptr // size on 64bit platforms
	}{
		{runtime.G{}, 272, 432},   // g, but exported for testing
		{runtime.Sudog{}, 56, 88}, // sudog, but exported for testing
	}

	for _, tt := range tests {
		want := tt._32bit
		if _64bit {
			want = tt._64bit
		}
		got := reflect.TypeOf(tt.val).Size()
		if want != got {

		close(c) // let select put its sudog's into the cache
		time.Sleep(1 * time.Millisecond)

		// pick up top sudog
		var cond1 sync.Cond
		var mu1 sync.Mutex
		cond1.L = &mu1
		go func() {
			mu1.Lock()
			cond1.Wait()
			mu1.Unlock()
		}()
		time.Sleep(1 * time.Millisecond)

		// pick up next sudog
		var cond2 sync.Cond
		var mu2 sync.Mutex
		cond2.L = &mu2
		go func() {
			mu2.Lock()
			cond2.Wait()

package runtime

import (
	"internal/cpu"
	"internal/runtime/atomic"
	"unsafe"
)

// Asynchronous semaphore for sync.Mutex.

// A semaRoot holds a balanced tree of sudog with distinct addresses (s.elem).
// Each of those sudog may in turn point (through s.waitlink) to a list
// of other sudogs waiting on the same address.
// The operations on the inner lists of sudogs with the same address

			}
		}
	}

	// lock all the channels involved in the select
	sellock(scases, lockorder)

	var (
		gp     *g
		sg     *sudog
		c      *hchan
		k      *scase
		sglist *sudog
		sgnext *sudog
		qp     unsafe.Pointer
		nextp  **sudog
	)

	// pass 1 - look for something already waiting
	var casi int
	var cas *scase
	var caseSuccess bool
	var caseReleaseTime int64 = -1

	//
	// Do not change another G's status while holding this lock
	// (in particular, do not ready a G), as this can deadlock
	// with stack shrinking.
	lock mutex
}

type waitq struct {
	first *sudog
	last  *sudog
}

//go:linkname reflect_makechan reflect.makechan
func reflect_makechan(t *chantype, size int) *hchan {
	return makechan(t, size)
}

func makechan64(t *chantype, size int64) *hchan {

// releaseSudog to allocate and free them.
type sudog struct {
	// The following fields are protected by the hchan.lock of the
	// channel this sudog is blocking on. shrinkstack depends on
	// this for sudogs involved in channel ops.

	g *g

	next *sudog
	prev *sudog
	elem unsafe.Pointer // data element (may point to stack)

< SCHED
# Below SCHED is the scheduler implementation.
< allocmR,
  execR;
allocmR, execR, hchan < sched;
sched < allg, allp;

# Channels
NONE < notifyList;
hchan, notifyList < sudog;

hchan, pollDesc, wakeableSleep < timers;
timers, timerSend < timer < netpollInit;

# Semaphores
NONE < root;

# Itabs
NONE
< itab
< reflectOffs;

# User arena state
NONE < userArenaState;

		// GC to avoid the following type of situation:
		//
		// 1) GC starts, scans a SudoG but does not yet mark the SudoG.elem pointer
		// 2) The stack that pointer points to is copied
		// 3) The old stack is freed
		// 4) The containing span is marked free
		// 5) GC attempts to mark the SudoG.elem pointer. The
		//    marking fails because the pointer looks like a
		//    pointer into a free span.
		//

func (d *dwctxt) synthesizechantypes(ctxt *Link, die *dwarf.DWDie) {
	sudog := walktypedef(d.findprotodie(ctxt, "type:runtime.sudog"))
	waitq := walktypedef(d.findprotodie(ctxt, "type:runtime.waitq"))
	hchan := walktypedef(d.findprotodie(ctxt, "type:runtime.hchan"))
	if sudog == nil || waitq == nil || hchan == nil {
		return
	}

	sudogsize := int(getattr(sudog, dwarf.DW_AT_byte_size).Value)

	for ; die != nil; die = die.Link {

	lockRankExecR:           "execR",
	lockRankSched:           "sched",
	lockRankAllg:            "allg",
	lockRankAllp:            "allp",
	lockRankNotifyList:      "notifyList",
	lockRankSudog:           "sudog",
	lockRankTimers:          "timers",
	lockRankTimer:           "timer",
	lockRankNetpollInit:     "netpollInit",
	lockRankRoot:            "root",
	lockRankItab:            "itab",