changes in sbcl-0.6.12 relative to sbcl-0.6.11:

* incompatible change: The old SB-EXT:OPTIMIZE-INTERFACE declaration
  is no longer recognized. I apologize for this, because it was
  listed in SB-EXT as a supported extension, but I found that
  its existing behavior was poorly specified, as well as incorrectly
  specified, and it looked like too much of a mess to straighten it
  out. I have enough on my hands trying to get ANSI stuff to work..
* many patches ported from CMU CL by Martin Atzmueller, with
  half a dozen bug fixes in pretty-printing and the debugger, and
  half a dozen others elsewhere
* fixed bug 13: Floating point infinities are now supported again.
  They might still be a little bit flaky, but thanks to bug reports
  from Nathan Froyd and CMU CL patches from Raymond Toy they're not
  as flaky as they were.
* The --noprogrammer command line option is now supported. (Its
  behavior is slightly different in detail from what the old man
  page claimed it would do, but it's still appropriate under the
  same circumstances that the man page talks about.)
* The :SB-PROPAGATE-FLOAT-TYPE and :SB-PROPAGATE-FUN-TYPE features
  are now supported, and enabled by default. Thus, the compiler can
  handle many floating point and complex operations much less
  inefficiently. (Thus e.g. you can implement a complex FFT
  without consing!)
* The compiler now detects type mismatches between DECLAIM FTYPE
  and DEFUN better, and implements CHECK-TYPE more correctly, and
  SBCL builds under CMU CL again despite its non-ANSI EVAL-WHEN,
  thanks to patches from Martin Atzmueller.
* various fixes to make the cross-compiler more portable to
  ANSI-conforming-but-different cross-compilation hosts (notably
  Lispworks for Windows, following bug reports from Arthur Lemmens)
* A bug in READ-SEQUENCE for CONCATENATED-STREAM, and a gross
  ANSI noncompliance in DEFMACRO &KEY argument parsing, have been
  fixed thanks to Pierre Mai's CMU CL patches.
* fixes to keep the system from overflowing internal counters when
  it tries to use i/o buffers larger than 16M bytes
* fixed bug 45a: Various internal functions required to support
  complex special functions have been merged from CMU CL sources.
  (When I was first setting up SBCL, I misunderstood a compile-time
  conditional #-OLD-SPECFUN, and so accidentally deleted them.)
* improved support for type intersection and union, fixing bug 12
  (e.g., now (SUBTYPEP 'KEYWORD 'SYMBOL)=>T,T) and some other
  more obscure bugs as well
* some steps toward byte-compiling non-performance-critical
  parts of the system, courtesy of patches from Martin Atzmueller
* Christophe Rhodes has made some debian packages of sbcl at
  <http://www-jcsu.jesus.cam.ac.uk/ftp/pub/debian/lisp>.
  From his sbcl-devel e-mail of 2001-04-08 they're not completely
  stable, but are nonetheless usable. When he's ready, I'd be happy
  to add them to the SourceForge "File Releases" section. (And if
  anyone wants to do RPMs or *BSD packages, they'd be welcome too.)
* new fasl file format version number (because of changes in
  internal representation of (OR ..) types to accommodate the new
  support for (AND ..) types, among other things)