* optimization: SB-SEQUENCE:DOSEQUENCE is faster on vectors of unknown
element type, and vectors that aren't SIMPLE-ARRAYs.
* bug fix: potential for infinite recursion during compilation of CLOS slot
* optimization: SB-SEQUENCE:DOSEQUENCE is faster on vectors of unknown
element type, and vectors that aren't SIMPLE-ARRAYs.
* bug fix: potential for infinite recursion during compilation of CLOS slot