// iteration of qualified exports
void PackageEntry::package_exports_do(ModuleClosure* const f) {
  assert_locked_or_safepoint(Module_lock);
  assert(f != NULL, "invariant");

  if (is_qual_exported()) { <<---
    int qe_len = _qualified_exports->length();

    for (int i = 0; i < qe_len; ++i) {
      f->do_module(_qualified_exports->at(i));
    }
  }
}

is_qual_exported() has been updated to:

  bool is_qual_exported() const {
    return (_is_exported && (_qualified_exports != NULL || _is_exported_allUnnamed));
  }

which means:
_qualified_exports->length(); is no longer safe.