	[z] = main <1>: , main <1, 2>: ?Mu1?, 2: ?Mu1?
	[y] = 1: 
	[Mu2] = 
	[Mu1] = 
	[#] = 
	[$] = 
	thread1(1:  | {a%13: <+ 0 +>}) = 1:  | {%ret%0: <+ 0 +>, a%13: <+ 0 +>}
	inc_z(2:  | {}) = 2:  | {x%16: <- ->, status%15: <- ->, post_22%22: <- ->}
	main(main <>:  | {}) = main <1, 2>:  | {tid2%21: <- ->, tid1%20: <- ->, %ret%0: <- ->}
	inc_z(main <1, 2>:  | {}) = main <1, 2>:  | {x%16: <- ->, status%15: <- ->, post_22%22: <- ->}
	thread2(2:  | {a%18: <+ 0 +>}) = 2:  | {%ret%0: <+ 0 +>, a%18: <+ 0 +>}
 