if nextIdx >= len(f.Blocks) { // reached end of function (maybe impossible?)
				break
			}
			nextb := f.Blocks[nextIdx]
			if nextb == p { // original loop predecessor is next
				break
			}
			if loopnest.b2l[nextb.ID] == loop {
				after[p.ID] = append(after[p.ID], nextb)
			}
			b = nextb
		}
		// Swap b and p so that we'll handle p before b when moving blocks.
		f.Blocks[idToIdx[loop.header.ID]] = p

	if id == "" {
		p.corner = true // goldmark accepts {#}
		return "", s
	}
	return s[i+2 : j], s[:i]
}

func newSetextHeading(p *parseState, s line) (line, bool) {
	var n int
	peek := s
	if p.nextB() == p.para() && peek.trimSetext(&n) {
		p.closeBlock()
		para, ok := p.last().(*Paragraph)
		if !ok {
			return s, false
		}
		p.deleteLast()

	for i := 0; i < 3 && tt.trimSpace(1, 1, false); i++ {
		m++
	}
	if !tt.trimSpace(1, 1, true) {
		n += m
		t = tt
	}

	// point of no return

	var list *listBuilder
	if c, ok := p.nextB().(*listBuilder); ok {
		list = c
	}
	if list == nil || list.bullet != rune(bullet) {
		// “When the first list item in a list interrupts a paragraph—that is,
		// when it starts on a line that would otherwise count as

	}

	return ps.root, ps.corner
}

func (p *parseState) curB() blockBuilder {
	if p.lineDepth < len(p.stack) {
		return p.stack[p.lineDepth].builder
	}
	return nil
}

func (p *parseState) nextB() blockBuilder {
	if p.lineDepth+1 < len(p.stack) {
		return p.stack[p.lineDepth+1].builder
	}
	return nil
}
func (p *parseState) trimStack(depth int) {
	if len(p.stack) < depth {
		panic("trimStack")

	XXLXOR  VS32, VS32, VS32 // clear VS32 (V0)
	SLD	$56, R5, R7
	STXVL   V0, R3, R7
	RET
#else
	CMP   R5, $4
	BLT   next2
	MOVW  R0, 0(R3)
	ADD   $4, R3
	ADD   $-4, R5
next2:
	CMP   R5, $2
	BLT   next1
	MOVH  R0, 0(R3)
	ADD   $2, R3
	ADD   $-2, R5
next1:
	CMP   R5, $0
	BC    12, 2, LR      // beqlr
	MOVB  R0, 0(R3)
	RET
#endif

    while (p->next_ != this) p = p->next_;
    p->next_ = next_;
    return false;
  }

 private:
  mutable linked_ptr_internal const* next_;
};

template <typename T>
class linked_ptr {
 public:
  typedef T element_type;

  // Take over ownership of a raw pointer.  This should happen as soon as
  // possible after the object is created.
  explicit linked_ptr(T* ptr = NULL) { capture(ptr); }

	type X struct {
		c     chan error
		nextx *X
	}
	type Y struct {
		X
		nexty *Y
		p     *int
	}
	var head *Y
	for i := 0; i < 10; i++ {
		p := &Y{}
		p.c = make(chan error)
		if head != nil {
			p.nextx = &head.X
		}
		p.nexty = head
		p.p = new(int)
		*p.p = 42
		head = p
		runtime.GC()
	}
	for p := head; p != nil; p = p.nexty {
		if *p.p != 42 {

	CMP	IN_LEN, $8
	BLT	next4
	MOVD	0(MASK_PTR), R14
	MOVD	0(BLK_INP), R15
	XOR	R14, R15, R14
	MOVD	R14, 0(BLK_OUT)
	ADD	$8, R16
	ADD	$-8, IN_LEN
next4:
	CMP	IN_LEN, $4
	BLT	next2
	MOVWZ	(BLK_INP)(R16), R15
	MOVWZ	(MASK_PTR)(R16), R14
	XOR	R14, R15, R14
	MOVW	R14, (R16)(BLK_OUT)
	ADD	$4, R16
	ADD	$-4, IN_LEN
next2:
	CMP	IN_LEN, $2
	BLT	next1

David Chase <******@****.***> 1579280635 -0500

David Chase <******@****.***> 1546465969 -0500