+?? minor incompatible change: The debugger prompt sequence now goes
+ "5]", "5[2]", "5[3]", etc. as you get deeper into recursive calls
+ to the debugger command loop, instead of the old "5]", "5]]",
+ "5]]]" sequence. (I was motivated to do this when squabbles between
+ ILISP and SBCL left me very deeply nested in the debugger. In the
+ short term, this change will probably provoke more ILISP/SBCL
+ squabbles, but hopefully it will be an improvement in the long run.)
+?? minor incompatible change: The default output representation for
+ unprintable ASCII characters which, unlike e.g. #\Newline, don't
+ have names defined in the ANSI Common Lisp standard, is now based
+ on their ASCII symbolic names: #\Nul, #\Soh, #\Stx, etc.
+?? Old operator names in the style DEF-FOO are now deprecated in
+ favor of new corresponding names DEFINE-FOO, for consistency with
+ the naming convention used in the ANSI standard (DEFSTRUCT, DEFVAR,
+ DEFINE-CONDITION, DEFINE-MODIFY-MACRO..). This mostly affects
+ internal symbols, but a few external symbols like
+ SB-ALIEN:DEF-ALIEN-FUNCTION are also affected.
+* minor incompatible change: DEFINE-ALIEN-FUNCTION (also known by
+ the old deprecated name DEF-ALIEN-FUNCTION) now does DECLAIM FTYPE
+ for the defined function, since declaiming return types involving
+ aliens is (1) annoyingly messy to do by hand and (2) vital
+ to efficient compilation of code which calls such functions (and
+ since people writing calls-to-C code aren't likely to be bothered
+ by implicit assumptions of static typing).
+* The value of INTERNAL-TIME-UNITS-PER-SECOND has been increased
+ from 100 to 1000.
+* The default value of *BYTES-CONSED-BETWEEN-GCS* has been
+ doubled, to 4 million. (If your application spends a lot of time
+ GCing and you have a lot of RAM, you might want to experiment with
+ increasing it even more.)
+* The interpreter, EVAL, has been rewritten. Now it calls the
+ native compiler for the difficult cases, where it used to call
+ the old specialized IR1 interpreter code.
+* The doc/cmucl/ directory, containing old CMU CL documentation
+ from the time of the fork, is no longer part of the base system.
+ SourceForge has shut down its anonymous FTP service, and with it
+ my original plan for distributing the old CMU CL documentation
+ there. For now, if you need these files you can download an old
+ SBCL source release and extract them from it.
+* lots of other tidying up internally: renaming things so that names
+ are more systematic and consistent, converting C macros to inline