It's not really a solution, but for people who are suffering from the infinite loop bug, you can change a couple things in ScmlPostProcessor.cs. Add a list to cache the cache:
private static IList<string> lastCachedPaths = new List<string>();
In OnPostProcessAllAssets() just before cachedPaths.Clear():
lastCachedPaths = new List<string>(cachedPaths);
In ProcessFiles(), just before cachedPaths.Add(path) add:
if (lastCachedPaths.Contains(path)) { Debug.LogError("Infinite loop on: " + path); continue;}
and after the foreach loop, before the end of the function:
lastCachedPaths.Clear();
It checks that the same file isn't being processed more than twice and, if it is, breaks out of the loop and logs an error. Obviously it doesn't fix anything, the assets don't get imported properly, but it stops your editor from locking up!