Incorrect offset assignment for metadata attributes

[netsys]

Incorrect offset assignment for metadata attributes

[barath]

Great catch. Just a general comment -- it would be nice to add a unit test that validates this once fixed (i.e., a unit test that fails currently due to this bug and that passes once the fix is committed). I figure you (Melvin) were probably going to do that anyway, but just wanted to add a reminder.

[melvinw]

It looks like the more general bug here is the following. AssignOffsets() breaks when one of the unassigned scope components (comp2) that is disjoint from the current scope component (comp1) is concocted in such a way that ComputeNextOffset() returns a value less than the current value of offset. I think the simple solution is to just change ScoreComponentComp so that scope components are popped off in strictly increasing order of the resulting offset instead of just the scope's offset field, as it does currently.

[melvinw]

An even simpler solution would be to just ignore the value of ComputeNextOffset() when it doesn't make sense.