Some call sites rely on these functions implicitly throwing exceptions as way to escape an assertion or invariant. This makes the failure modes hard to reason about, and complicates the introduction of new error codes.

Make uassertWTOK, invariantWTOK and wtRCToStatus not throw exceptions. Introduce uassertWTOKMayThrow, invariantWTOKMayThrow, wtRCToStatusMayThrow which effectively implement the current API behaviour and which can throw an exception in some documented cases.