// and without worrying about the stack moving out from under us
	// (because we're on a system stack, not a goroutine stack).
	// The above code could be used directly if already on a system stack,
	// but then the only path through this code would be a rare case on Solaris.
	// Using this code for all "already on system stack" calls exercises it more,
	// which should help keep it correct.
	SUBQ	$16, SP

		// on another stack. That could confuse callers quite a bit.
		// Instead, we require that initAt and any other function that
		// accepts an sp for the current goroutine (typically obtained by
		// calling getcallersp) must not run on that goroutine's stack but
		// instead on the g0 stack.
		throw("cannot trace user goroutine on its own stack")
	}

	}

	var state stackScanState
	state.stack = gp.stack

	if stackTraceDebug {
		println("stack trace goroutine", gp.goid)
	}

	if debugScanConservative && gp.asyncSafePoint {
		print("scanning async preempted goroutine ", gp.goid, " stack [", hex(gp.stack.lo), ",", hex(gp.stack.hi), ")\n")
	}

	// Scan the saved context register. This is effectively a live
	// register that gets moved back and forth between the

// A StackRecord describes a single execution stack.
type StackRecord struct {
	Stack0 [32]uintptr // stack trace for this record; ends at first 0 entry
}

// Stack returns the stack trace associated with the record,
// a prefix of r.Stack0.
func (r *StackRecord) Stack() []uintptr {
	for i, v := range r.Stack0 {
		if v == 0 {
			return r.Stack0[0:i]
		}
	}
	return r.Stack0[0:]
}

		re1 := p.stack[n-1]
		re3 := p.stack[n-3]
		// Make re3 the more complex of the two.
		if re1.Op > re3.Op {
			re1, re3 = re3, re1
			p.stack[n-3] = re3
		}
		mergeCharClass(re3, re1)
		p.reuse(re1)
		p.stack = p.stack[:n-1]
		return true
	}

	if n >= 2 {
		re1 := p.stack[n-1]
		re2 := p.stack[n-2]
		if re2.Op == opVerticalBar {
			if n >= 3 {

			{
				entry: &dwarf.Entry{
					Offset:   0xb,
					Tag:      dwarf.TagCompileUnit,
					Children: true,
					Field: []dwarf.Field{
						{Attr: dwarf.AttrProducer, Val: "GNU C 4.8.2 -g -fstack-protector", Class: dwarf.ClassString},
						{Attr: dwarf.AttrLanguage, Val: int64(1), Class: dwarf.ClassConstant},
						{Attr: dwarf.AttrName, Val: "go-relocation-test-gcc482.c", Class: dwarf.ClassString},

		}

		systemstack(func() {
			// Mark our goroutine preemptible so its stack
			// can be scanned. This lets two mark workers
			// scan each other (otherwise, they would
			// deadlock). We must not modify anything on
			// the G stack. However, stack shrinking is
			// disabled for mark workers, so it is safe to
			// read from the G stack.
			//
			// N.B. The execution tracer is not aware of this status

				t.Fatalf("want stack stack root %s, got %v", wantFn, rootFn)
			}
		})
	}
}

func hasPrefix(stk []string, prefix []string) bool {
	if len(prefix) > len(stk) {
		return false
	}
	for i := range prefix {
		if stk[i] != prefix[i] {
			return false
		}
	}
	return true
}

// ensure that stack records are valid map keys (comparable)

	var stack []*loadPkg
	for p := pkg; p != nil; p = p.stack {
		stack = append(stack, p)
	}

	var buf strings.Builder
	for i := len(stack) - 1; i >= 0; i-- {
		p := stack[i]
		fmt.Fprint(&buf, p.path)
		if p.testOf != nil {
			fmt.Fprint(&buf, ".test")
		}
		if i > 0 {
			if stack[i-1].testOf == p {
				fmt.Fprint(&buf, " tested by\n\t")
			} else {
				fmt.Fprint(&buf, " imports\n\t")

	if err != nil {
		klog.ErrorS(err, "Unable to determine dual-stack status, falling back to single-stack")
		return false
	}

	if utilfeature.DefaultFeatureGate.Enabled(kubefeatures.WinOverlay) && isOverlay(networkInfo) {
		// Overlay (VXLAN) networks on Windows do not support dual-stack networking today
		klog.InfoS("Winoverlay does not support dual-stack, falling back to single-stack")
		return false
	}

	return true
}