changes in sbcl-1.4.11 relative to sbcl-1.4.10:
* minor incompatible change: changes to the (internal) assembler on x86
and x86-64 may cause problems to some low-level third-party libraries:
** new macro EA for defining an effective address, without size
information;
** an explicit size modifier is now needed for MOVSX and MOVSZ
instructions;
** MOVD and MOVQ move a single size of operand by definition.
* enhancement: support the latest MinGW (lp#1786731, reported by il71)
* enhancement: checks for modifications of constants can now be done in
local (FLET/LABELS) functions.
* optimization: improved type checking routines for various compound types.
* optimization: array bound checks are elided on vectors when the index is
known to be less than the length, including LOOP ACROSS.
* optimization: the register allocator's use of temporaries is somewhat
improved.
* optimization: checking widetags involves fewer conditional jumps on x86
and x86-64.
* bug fix: fix a number of bugs related to constant improper lists as
sequence arguments (lp#1768563, lp#1768568, lp#1768652)