The patch for https://clojure.atlassian.net/browse/CLJ-979#icft=CLJ-979 exposed an issue with how clojure.core/compile is implemented, which causes the bug reported here: https://groups.google.com/d/msg/clojure-dev/jj87-4yVlWI/YKG4QazhPuAJ

The cause of this regression is that clojure.core/compile doesn't take into account clojure.core/loaded-libs, causing

to reload 'some-ns from the AOT class with the call to compile.

Since the AOT compiled namespace is not loaded by DynamicClassLoader but using the underlying java.net.URLClassLoader, code that relies on deftypes will have references to the AOT versions hardcoded, breaking the class loading policy introduced with https://clojure.atlassian.net/browse/CLJ-979#icft=CLJ-979 of prefering the in-memory versions to the AOT ones.

The fix for this, as implemented in the attached patch, is to make compile loaded-libs-aware, so that it won't force any namespace re-loading when unnecessary.