Weak partial order implementation

[arthaud]

See facebook/SPARTA#5 (comment), that could impact our implementation too.

[ivanperez-keera]

@arthaud Nothing was ever done on this. This is actionable? Do you still think this is high priority?

[arthaud]

I think we would need to port facebook/SPARTA#7 into IKOS.
It doesn't seem high priority though since we haven't noticed any concrete problems in IKOS's fixpoint.

[ivanperez-keera]

Ok. I'm going to move it to discussions as an idea, just to keep the issue list for items whose progress we are actively tracking. We can move it back if we start working on this in the future.

Thanks!