changes in sbcl-0.9.1 relative to sbcl-0.9.0:
* fixed cross-compiler leakages that prevented building a 32-bit
target with a 64-bit host compiler.
+ * compiled code is not steppable if COMPILATION-SPEED >= DEBUG.
* contrib improvement: implement SB-POSIX:MKSTEMP (Yannick Gingras)
* optimization: There's now a fast-path for fixnum arguments in the
generic subtraction routines on x86/x86-64. (Thanks to Lutz Euler)