X nodes with fanins pull-off: 
	0	a : 1
	0	b : 0
X nodes with fanins pull-off: 
c
	0	a : 0
	10	c : 1	[by a:=0]
X nodes with fanins pull-off: 
	10	a : 1
X nodes with fanins pull-off: 
	10	b : 1
	20	c : 0	[by b:=1]
X nodes with fanins pull-off: 
	20	b : 0
X nodes with fanins pull-off: 
	20	a : X
	30	c : X	[by a:=X]
X nodes with fanins pull-off: 
WARNING: weak-interference `c'
>> cause: `b' (val: X)
	30	b : X
X nodes with fanins pull-off: 
