sbcl-2.6.6 released

Dear all,

SBCL 2.6.6 is now tagged in revision control, and a source archive
available from SourceForge.  Particularly notable changes in this
release are summarized below.

Christophe

changes in sbcl-2.6.6 relative to sbcl-2.6.5:
  * minor incompatible change: FDEFINITION now returns the outermost wrapper
    (added e.g. by TRACE, PROFILE) like SYMBOL-FUNCTION.  (lp#799533)
  * minor incompatible change: in unsafe code, C strings with :EXTERNAL-FORMAT
    :ASCII are copied directly as byte-sized quantities without checking
    whether the top bit of the byte is set.
  * platform support:
    ** fix the build on big-endian 64-bit PowerPC with ELFv2.  (thanks to
       Piotr Kubaj)
    ** move the static space address for macOS 27 on ARM64.  (lp#2156072,
       reported by Gary Palter)
    ** optimizations to SB-THREAD:BARRIER for ARM64.  (thanks to Sahil Kang)
    ** fix a compiler crash in MULTIPLE-VALUE-LIST in argument forms on ARM64.
       (lp#2155788, reported by Gary Palter)
  * bug fix: TRACE no longer fails when trying to print a return value that
    cannot be printed readably and *PRINT-READABLY* is true.
  * optimization: the compiler is more precise in its type derivation of
    COERCE given constraints on its inputs.
  * optimization: the compiler is better able to derive the return types of
    AREF and ELT.
  * optimization: faster encoding and decoding of UTF-8 C strings.
  * optimization: (length (intersection a b)) doesn't cons an intermediate
    list.
  * documentation: the manual now includes a section for SB-INTROSPECT, which
    has also seen improvement in its documentation strings and comments.
  * documentation: fixed many typesetting problems and typos in the user
    manual.