grounding in the PCL implementation of CLOS.
* bug fix: TRUENAME on "/" no longer returns a relative pathname.
(reported by tomppa on #lisp)
+ * bug fix: clear the direction flag on Lisp -> C transitions, as
+ required by the x86-64 ABI. Fixes mysterious GC crashes on SuSE.
+ (reported by Andrej Grozin and Hendrik Maryns)
* optimization: major improvements to GC efficiency on GENCGC platforms
* optimization: faster implementation of EQUAL
* optimization: emit more efficient opcodes for some common