triage: P-high to investigate
So, I see the first example as a case that we should ultimately try to catch and give a better error for (as we do for more direct circular structs). But I don't think it's terribly urgent, personally. For the second case: I suspect that this is fundamental. That is, the proof search for traits fundamentally relies on an overflow cutoff to avoid infinite loops, and the fact that specialization lets you dispatch on types will always mean that you can selectively create these overflowing situations. I see the "blame" here as mostly the fact that the trait system can fail due to overflow, but that's inevitable in having as powerful of a system as we do. I'm going to renominate for triage of the bug listed in the top comment, which we could try to provide a better error for. I suggest that this is P-low, however. triage: I-nominated
triage: P-high
triage: P-high
triage: P-high