obscure ANSI requirements
changes in sbcl-0.8.4 relative to sbcl-0.8.3:
+ * incompatible change: The --disable-debugger command line
+ option now clobbers the debugger at a more fundamental
+ level, by redefining #'INVOKE-DEBUGGER instead of by
+ rebinding *DEBUGGER-HOOK*. The main difference is that BREAK
+ is specified by ANSI to ignore *DEBUGGER-HOOK* and
+ INVOKE-DEBUGGER regardless. Under the old system, BREAK would
+ enter the debugger REPL and then suffer recursive errors
+ because *DEBUG-IO* is also messed up in --disable-debugger mode;
+ while under the new system, BREAK in --disable-debugger mode
+ terminates the system just as an unhandled error would.
* fixed compiler performance when processing loops with a step >1;
* bug fix: DOCUMENTATION now retrieves generic function
documentation. Also, DOCUMENTATION and (SETF DOCUMENTATION)
combination. (reported by Andreas Fuchs)
* bug fix: RUN-PROGRAM now does not fail if some element in $PATH
names a non-existent directory. (thanks to Andreas Fuchs)
+ * bug fix: ROUND and TRUNCATE could, under certain circumstances on
+ the PPC platform, lead to stack corruption; this has been fixed.
+ (reported by Rainer Joswig)
+ * bug fix: ASH on an (UNSIGNED-BYTE 32) with a shift of -32 or lower
+ no longer ever returns 1 instead of 0. (thanks to Lars Brinkhoff)
+ * fixed bug 285: TRUNCATE on bignum arguments, and indeed bignum
+ arithmetic in general, is now much more reliable on the PPC
+ platform.
* optimization: restored some effective method precomputation in
CLOS (turned off by an ANSI fix in sbcl-0.8.3); the amount of
precomputation is now tunable.
* optimization: compiler-internal data structure use has been
reviewed, and changes have been made that should improve the
performance of the compiler by about 20%.
+ * optimization: performance of FILL (and :INITIAL-ELEMENT) on
+ simple-base-strings and simple-bit-vectors is improved.
* microoptimization: the compiler is better able to make use of the
x86 LEA instruction for multiplication by constants.
* bug fix: in some situations compiler did not report usage of
generic arithmetic in (SPEED 3) policy.
+ * bug 145b fix: compiler used wrong type specifier while converting
+ MEMBER-types to numeric.
+ * bug fix: COMPILE-FILE must bind *READTABLE*. (reported by Doug
+ McNaught)
+ * fixed some bugs revealed by Paul Dietz' test suite:
+ ** the RETURN clause in LOOP is now equivalent to DO (RETURN ...).
+ ** ROUND and FROUND now give the right answer when given very
+ small float arguments.
+ ** (FLOAT X) for X of type DOUBLE-FLOAT now returns X in all
+ circumstances.
+ ** optimizer for (EXPT X 0) did not work for X not of type FLOAT.
+ ** (GCD 0 <negative-integer>) returned <negative-integer>.
+ ** LCM should return a non-negative integer.
+ ** PARSE-INTEGER returned the index of a terminator instead of the
+ upper bounding index of a substring in case :JUNK-ALLOWED NIL.
+ ** PARSE-INTEGER returned an incorrect index being applied to a
+ displaced string.
+ ** LCM with two arguments of 0 returns 0 rather than signalling
+ DIVISION-BY-ZERO.
+ ** unsigned addition of a 32-bit constant with the high bit set no
+ longer causes an internal compiler error on the x86.
+ ** LOGBITP accepts a non-negative bignum as its INDEX argument.
+ ** compiler incorrectly derived types of DPB and DEPOSIT-FIELD
+ with negative last argument.
+ ** byte specifiers with zero size and position no longer cause
+ an error during type derivation.
planned incompatible changes in 0.8.x:
* (not done yet, but planned:) When the profiling interface settles