+ * optimization: EQUAL hash tables no longer use SXHASH for objects
+ of all data types, but instead use an EQL hash for types for which
+ EQUAL is the same as EQL.
+ * optimization: the non-inlined generic versions of AREF and (SETF AREF)
+ are significantly faster.
+ * optimization: new STRING-OUTPUT-STREAM implementation is much
+ faster for large outputs and conses 30% less on average.
+ * enhancement: XREF information is now collected for references made