Changes in YAP4.5
Yap-4.5.3:
	
Changes in YAP4.3
Yap-4.3.23:
	- UPDATE: new Logtalk version (2.15.2).
- NEW: hide_predicate/1. (request from Paulo Moura)
- NEW: support condor.
- FIXED: bug in waking up attached variables (summer@mail.sc.cninfo.net).
- FIXED: extra manual bugs (Maleeha Qazi).
- UPDATE: updated configure.infor smooth YAP compilation on MacOS X 10.2.
- FIXED: rintis nottruncate/1(Paulo Moura).
- FIXED: recent change broke debugger help message (Nuno Fonseca).
- NEW: call_with_args/nsimulatescall/n.
- FIXED: have different types for Atom,Term, andFunctorinc_interface.
- FIXED: make call_with_args/*check if first arg is atom.
- FIXED: make cd/1complain on bugs.
- FIXED: always do something on gmpallocation (request from
	Roberto Bagnara).
- FIXED: always allow abolish on static predicates.
- UPDATE: include new apply_macroscode from Erick Alphonse,
	and acknowledge J. Schimpf.
- FIXED: YapRunGoal(Roberto Bagnara).
- NEW: term_positionoption forread_term(Nicos)
- UPDATE: fixed shell/1andshell/2in library(system). (Nicos)
- FIXED: \newlinein strings (Roberto Bagnara).
- FIXED: avoid reincluding of c_interface.h(Roberto
	Bagnara).
- FIXED: make c_interface.hcompilable in C++ (Roberto
	Bagnara).
- FIXED: garbage collector should recover dynamic clauses
	and logical semantics DB. Trust gc to recover active clauses 
- FIXED: read_varswas called with unbound argument.
- FIXED: backtrackable C-predicates (thanks to Christophe
	Billard for sending the file).
- FIXED: new options for file_property(Nicos).
- FIXED: check unification result in file_property(Nicos).
- FIXED: yap_flag(fileerrors)(Nicos).
- FIXED: clauses with blobs cannot be simply abolished.
- FIXED: retract of undefined predicate makes it dynamic.
Yap-4.3.22:
	- FIXED: default syntax error mode should be error.
- NEW: atom garbage collector.
- FIXED: recover space for logical update semantics.
- FIXED: smash references to deleted entries with logical
	update semantics.
- FIXED: make instance of deleted fail for logical
	update semantics.
- FIXED: garbage_collectshould calldo_gcwithP, notCP.
- FIXED: use YAPSHAREDIRas in manual (Ashwin Srinivasan).
- FIXED: warning message about unify_extension.
Yap-4.3.21:
	- FIXED: syntax errors dumped all numbers as if small integers.
- UPDATE: new Logtalk version (2.10.0).
- FIXED: debugger could enter infinite loop if spying
	portray(Steve Moyle).
- FIXED: predicate_property(P,source)(Ines Dutra).
- NEW: use system regex routines if available.
- FIXED: profiling.
- FIXED: Yap in CYGWIN, including DLLs.
- NEW: variable_in_term/2atlibrary(terms).
- FIXED: debugger would not step through [-F].
- FIXED: unix(argv(L))was doing bad type checking.
- FIXED: assert((a:- m:[f]))would core dump.
- FIXED: gc in dexecuteshould not use currentY, instead if
	should look at parent'sY(Ines Dutra).
- FIXED: do not loop on unbound metacalls.
- FIXED: do not assert clauses if the predicate is active
	and you had to abolish first.
- FIXED: always allow asserting over static predicates.
- FIXED: disable cache when checking whether static was
	in use.
- FIXED: heap overflow while storing dbterm.
- FIXED: trust_failshould be preceeded by ansla.
- FIXED: make slapoint to current pred, get rid of current
	pred in bitmap.
- FIXED: MkVarTerminc_interface.h(Christophe Billard)
- FIXED: get rid of unnecessary USE_OFFSETS
- FIXED: stupid limit on Heap Size with LowTags. (David Page)
- FIXED: make fileerrorsdefault for SICStus. (Nicos Angelopoulos)
- FIXED: g(X) :- (Z is 2*X; a(Z)):Zcannot be seen as a free
	var. (Nicos Angelopoulos).
- FIXED: atom_concatwas not allocating heap correctly (Nicos Angelopoulos).
- NEW: ord_intersection/4(Nicos Angelopoulos).
- NEW: file_search_path/2(Nicos Angelopoulos).
- FIXED: fix yap_flag(host_type).
- FIXED: make Yap compile under VC++ again.
- FIXED: don't try to handle X/0the ISO way.
- FIXED: make Yap runnable in WIN98.
- FIXED: access to non-existing dynamic array should not core-dump.
- FIXED: abolish(_)should give error in ISO mode.
- NEW: yap_flag(argv,L)(Nicos Angelopoulos).
- FIXED: make userthe name of the first three streams.
- NEW: reachable/3in ugraphs (Nicos Angelopoulos).
- NEW: -fflag in boot (Nicos Angelopoulos).
- FIXED: manual html warnings (Nicos Angelopoulos).
- NEW: yap_flag(informational_messages)allows disabling
	informational messages (Nicos Angelopoulos).
- FIXED: lccwould choke when compiling Yap.
- FIXED: simplesimmiscompilations.
- FIXED: more SICStus like top-level messaging (Nicos Angelopoulos).
- FIXED: missing WIN32 interface declaration (Christophe Billard).
- FIXED: alarmwas not working in WIN32 (Tolga Konick).
- FIXED: get0/2andget/2should call$getdirectly.
- CHANGE: make full leash default.
- NEW: continue creeping after a goal. (Ines Dutra)
- FIXED: creepshould not creep the whole debugger.
- FIXED: breakshould not start the whole system.
- FIXED: abolishcould backtrack and give weird error (Nicos
	Angelopoulos).
- FIXED: make consult,use_module, and friends meta-predicates
	(Nicos Angelopoulos).
- FIXED: make use_modulea directive.
- FIXED: predicate_property/2to handle modules correctly
	(Nicos Angelopoulos).
- FIXED: stack expansion in meta-execution.
- FIXED: depth_limitwas not handled correct in
	meta-execution of conjunctions (Rui Camacho).
- NEW: new option for error handling in the debugger.
- UPDATE: new version of Logtalk.
- FIXED: heap library.
- NEW: empty_heap/3.
- FIXED: some system predicates are exported outside the
	prolog module.
- FIXED: calls to open/3,current_stream/3,tab/{1,2}, andformat/3might interfere with trace.
- NEW: new catch/3andthrow/1mechanism.
- FIXED: p_socketwould crash if no streams were
	available (Ines Dutra).
- FIXED: CLPQR complaints on importing private predicates.
Yap-4.3.20:
	- FIXED: 'aaaa''xaaa'was insertingxinstead of'(Miguel Filgueiras).
- FIXED: fix CHR using merge from prolog instead of ordsets.
- FIXED: store infinite terms in DB properly (at last).
- FIXED: execute_7(Paulo Moura).
- FIXED: expand meta-call arguments even if they are
	built-ins (otherwise breaks bb_*).
- FIXED: always generate FATAL_ERRORonSIGSEGV.
- FIXED: another GC bug.
- FIXED: phrase/2andphrase/3are meta-predicates.
- FIXED: use TRinstead ofHfor system.
- FIXED: absolute_file_name/2should be SICStus compatible (Nicos Angelopoulos).
- FIXED: put < debugger back to work (Ines Dutra).
- FIXED: make remandmodISO-compatible operators (Paulo Moura).
- FIXED: expand consult stack when there are too many
	predicates (David Page).
- FIXED: create DLs even when you don't need .so.
- FIXED: abolish/1.
- NEW: try to make module system really compatible.
- CLEANUP: don't use state of Pred.
- SPEEDUP: improve predicate access by linking predicates to
	functors.
- FIXED: listingbroke whencurrent_predicatebecame meta.
- FIXED: consultshould not erase dynamic clauses (report
	from James Cussens).
- FIXED: check if we still can do garbage collection (MBITandRBITok)  (report from James Cussens).
- FIXED: always release stack after InitBigNum(report from
	Nicos Angelopoulos).
- FIXED: randomwould not load in windows (report from
	Henrik Boström).
- FIXED: don't send warnings about repeated predicates from
	different modules (report from Henrik Boström).
- NEW: socket_buffering/4(report from Henrik Boström).
- FIXED: current_hostname/1tocurrent_host/1(report from
	Henrik Boström).
- FIXED: socket_select/5was completely broken (report from
	Henrik Boström).
- FIXED: avoid unnecessary choice-point in
	yap_flag(user_*,Who)(report from Nicos Angelopoulos).
- FIXED: flushshould work with readline.
- FIXED: reset alarm at top-level.
- FIXED: do signal(ALARM)immediately.
- FIXED: don't use full optimization for parser.cin cygwin
	(report from Steve Moyle).
- NEW: Erik Alphonse's apply_macros library.
- FIXED: ord_del_element/3(Nicos Angelopoulos).
- FIXED: texinfo warnings (Stasinos).
- FIXED: under emacs/win32: prompt if $EMACS=t and buf NULL.
- FIXED: ^Candreadline(I hope).
- NEW: traceandnotrace.
- FIXED: make C-c tactually trace.
- FIXED: put [debug]when in debug mode.
- FIXED: make install_info(actual fix is in Yap-4.3.19).
Yap-4.3.19:
	- FIXED: fflush(NULL)broken in some machines (Stasinos).
- FIXED: don't flush input streams (Stasinos).
- FIXED: new statistics/0.
- FIXED: use 15 bits of precision for floats, instead of the
	default 6..
- FIXED: check for last file modification in use_module.
- FIXED: get_list+unify_localwas being compiled intoglval, breakingENVvars
- FIXED: abortwas crashing in Alpha machines.
- FIXED: make ^c-awork within gc.
- FIXED: handle correctly very deep nested terms while gc
	marking.
- FIXED: ArityOfFunctorwas giving trouble with HP-UX cc
	(Stasinos Konstantinos).
- FIXED: ^cworks with Yap/MINGW32 (not in cygwin).
- FIXED: ^ca should never core dump.
- FIXED: comparison of variables in sub-terms.
- FIXED: parse +inf, -inf, +nan, -nan as floats and write
	them accordingly.
- FIXED: comparison was breaking ISO.
- FIXED: use $(CC)nevergccdirectly.
- FIXED: support newer versions of readline by moving text
	to prompt.
- FIXED: upgrade to autoconf 2.5.
- FIXED: catchandthrowshould not leave unnecessary
		choice-points behind.
- FIXED: make catch cleanup queue of findall entries.
- FIXED: change catch/3andthrow/1to use arrays.
- CLEANUP: split TRAIL_REF.
- FIXED: give correct type to FreeBlocks.
- FIXED: give correct type to alias list.
- FIXED: format ~NNwasn't implemented (report from Markus Walther).
- DELETED: shell/1is now available through system library.
- FIXED: !/0in meta-call wasn't cutting.
- FIXED: MkLongIntTerm(from Stasinos Konstantinos).
- NEW: Logtalk OO library (from Paulo Moura).
- FIXED: CHR instalation.
- SPEEDUP: avoid unnecessary choice-points with CLPQR.
- NEW: inline $mod_switch,$mod_switchnow uses
	backtrackable updates to modules.
- NEW: new method for marking timestamps that simplifies gc
- FIXED: bug while collecting multi-assignment variables
- FIXED: make yap modules more compatible with SICStus Prolog
- NEW: portray_clause/2(request from Nicos Angelopoulos)
- FIXED: document absolute_file_name/2
- FIXED: absolute_file_name/2should return absolute path, never user name! (bug report from Nicos Angelopoulos)
- FIXED: in a:-b:call(X)Xbelongs to the moduleb(bug report from Nicos Angelopoulos)
- FIXED: make consult/1and friends meta-predicates (bug report from Nicos Angelopoulos)
- FIXED: allow [M:F]and friends (bug report from Nicos Angelopoulos)
- FIXED: ensure_loaded/1can be used as a goal (bug report from Nicos Angelopoulos)
- FIXED: abolish(VAR)should abolish all predicates in current module (bug report from Nicos Angelopoulos).
- NEW: library(system), only for Unix system right now.
- FIXED: allow current_stream/3to work with third argument known.
- FIXED: always leave enough space so that the hybrid garbage collection may work.
- FIXED: add_to_pathshould not leave choice-points.
- FIXED: don't initialise first occurrences in branches for func outputs.
- FIXED: handle void variables in body.
- NEW: externd C-interface with StreamToFileNo,BufferToString, andBufferToAtomList.
- NEW: support pipes with open_pipe_stream/2.
- FIXED: functor/3was generating too many deallocates at the end of a clause.
- FIXED: call_residue/2should not allow constraints to escape (usecopy_term_no_variables/2to avoid this).
- SPEEDUP: optimise away true/0at the end of a clause.
- FIXED: do not short circuit trail entries.
- FIXED: Patches for memory allocation in Apple's OS/X.
- FIXED: checked whether mmapwork right inalloc.c.
- FIXED: ASPfromYshould have space forenvsize.
- NEW: new garbage collection algorithm.
- FIXED: don't allow importing from the module itself.
- FIXED: force line buffering for text stream.
- FIXED: force no buffering for user_error.
- FIXED: flush all streams before writing answer.
- FIXED: YP_std*are now streams, so thatyap_flag(user_*)will change them too.
- FIXED: nth/3andnth0/3would leave one extra choice-point.
- FIXED: use Contentsinstead ofUsesto determine live variables.
- FIXED: cputimewas actuallywalltimein WIN32, ugh (report from Steve Moyle).
- FIXED: regexp library would not compile on recent versions of cygwin.
- FIXED: change first two arguments of add_vertices/3for SICStus compatibility (report from Nicos Angelopoulos).
- NEW: sum_list/2(request from Nicos Angelopoulos).
- FIXED: ord_union/2should not use usemerge/3but insteadord_union/3(report from Nicos Angelopoulos).
- FIXED: statistics/0should report touser_error(report from Nicos Angelopoulos).
- FIXED: database could copy compiled floats, longs, and bigs to Heap, later crashing the garbage collector (report from Nicos Angelopoulos).
- NEW: if/3(request from Nicos Angelopoulos).
- SPEEDUP: inline functor(S) -> Na,Ar.
- SPEEDUP: inline functor(Na,Ar) -> S.
- FIXED: pillow installation path.
- FIXED: allow yap_flag(user_{},V).
- FIXED: allow second argument unbound to stream_property/2.
- FIXED: alias change had  broke stream_property/2.
- FIXED: alias change had broke tell(user)andsee(user).
- SPEEDUP: inline arg/3.
- FIXED: extra clause for module/1.
- NEW: module/3: SICStus options plus ciao options.
- FIXED: mode/1 should not be defined if we do not know what to do about it.
- NEW: prolog_flag(version,X).
- FIXED: understand 0'\escape sequences.
- NEW: atom_concat/2(idea from ciao).
- NEW: list_concat/2inlibrary(lists)(idea from ciao).
- NEW: allow profile early reset in garbage collector.
- FIXED: call_residueshould *unify* back constraints *after* restoring original suspension lists.
- FIXED: include Mandrake's $(DESTDIR)patches in Makefiles (by Lenny Cartier).
- FIXED: close(user_error)now closes stream currently associated withuser_error.
- FIXED: open(user_*,X,Y)is not special any longer (SICStus compatibility).
- FIXED: prolog_flag({max,min}_integer,X)with GMP.
- FIXED: prolog_flag(bounded,false)with GMP.
- NEW: prolog_flag(user_{input,output,error},X)(request from Nicos Angelopoulos).
- FIXED: allow close(file_alias).
- FIXED: user_input,user_output, anduser_errorare now aliases, like all the others.
- FIXED: restore YapLibDir.
Yap-4.3.18:
	- FIXED: alignment bug with walltimein sparc/solaris.
- FIXED: shunting in garbage collector.
- FIXED: restore arithmetic operators was broken.
- FIXED: restore arrays had never been implemented.
Yap-4.3.17:
	- FIXED: recording floating point numbers was broken (report from Ashwin Srinivasan).
- FIXED: restore bitmap Predpointers from calls.
- FIXED: restore masks when adjusting the data base.
- FIXED: handle pointers to HeapandApplstoTrailcorrectly ingrow().
- FIXED: db terms with variables must be adjusted from correct offset (restore db).
- FIXED: atomic terms do not need masks (restore db).
- FIXED: complex terms in db may also have variables (restore db).
- FIXED: functors are never offsets (sshift).
- FIXED: check for NULLpointers when restoring FreeSpace mm.
- FIXED: make gcc -mno-cygwindefault incygwinenvironment.
- FIXED: kill COMPRESS_DB_TERMand use new rational tree scheme for DB instead.
- FIXED: use new rational_treescheme inarrays.c,cmmpreds.c, andcorout.c.
- FIXED: make variant/2,term_variables/2, and friends use newrational_treescheme.
- FIXED: make copy_term/2use newrational_treescheme.
- FIXED: don't test for age in unify.c.
- NEW: cyclic_term/1andacyclic_term/1intermslibrary.
- FIXED: use RATIONAL_TREESscheme to inunify_with_occurs_check/2.
- FIXED: unify_with_occurs_check/2.
- FIXED: make Yap run under SGI's gcc -mabi=64(gcc buggy? Needs testing).
- FIXED: make Yap run under SGI's cc -64.
- FIXED: fix alignment bug for 64bits in AllocCMem.
- FIXED: make Yap run under HP-UX's cc.
- FIXED: avoid labels before brackets with HP-UX cc.
- FIXED: get rid of huge masks in dbase.c.
- FIXED: make Yap run under SGI's cc.
- FIXED: avoid smart comparison in non-GNUCC compilers.
- FIXED: get rid of unused variables.
- FIXED: get rid of warnings with enumtypes.
- NEW: number_atom/2.
- FIXED: purge unnecessary unify_lvar X0with inunify_n_voids_last.
- FIXED: make it compile again under cygwin pure.
- FIXED: documentation for pillow.
- FIXED: use Yap.specand/usr/share/infofor recent rpms.
- FIXED: configurewould check forlimits.htwice.
Yap-4.3.16:
	- FIXED: handle trail segments when growing heap or local (tabulation).
- FIXED: fix backtracking with multi-assignment variables (bug report from Bart Demoen).
- FIXED: only insert into relocation chain if heap pointer.
- FIXED: handle overflows in substitution stack for tabulation.
- FIXED: documentation bug in CHR.
- FIXED: how to include opt.mavar.h(bug report from Luis Fernando).
- FIXED: trail overflow while doing gc (bug report from GJVanNoord).
- FIXED: System would lose []because the atom looked likeNULL(bug report from Rui Camacho).
Yap-4.3.15:
	- FIXED: garbage collector now marks all local variables so that we can do early reset on local variables.
- FIXED: support second quadrant machines in new scheme for large numbers.
- NEW: ord_setproduct/3inlibrary(ordsets).
- NEW: garbage collection for tabled computations.
- FIXED: garbage_collect/0shouldn't affect gc heuristics.
- NEW: OPTYap's latest tabulation code.
- FIXED: respect debugger printining options.
- FIXED: make sure variables are globalised before spying.
- FIXED: tabling in autoconf.
- SPEEDUP: improve variable unification where we know one of the variables is in the heap.
- FIXED: when sweeping garbage collector should check for variables posing as blobs (USE_OFFSETS).
- FIXED: reduce overheads in functor/3.
- FIXED: variantandsubsumesmust check functor and must check for extensions.
- FIXED: activate dorming optimised instructions and fix glist_void_var.
- FIXED: performance bug in new multiplication code (only for i386).
- FIXED: exit at Error()inError().
- FIXED: grow()had trouble with array ptrs in Trail.
- FIXED: include Stasinos patches for gmp, HP-UX and on documentation.
- FIXED: recorda_stat_sourcewas passing 0 instead of tagged 0, also alwaysinitialise ->code!
- FIXED: accept multiple block declarations and process them as a conjunction.
- FIXED: call_residue/2.
- FIXED: block even when you have no - modes.
- FIXED: use mkstemp()instead oftmpnam()inalloc.c.
- FIXED: now I can wake up goals at disjunction, see merge(A,[2],C), A = [1|B], (B = [2]; B = [3]). I had to save temporary registers in a term. Checkpush_live_regsandrestore_regs()for details.
- FIXED: ->pfield of either now points to true.
- FIXED: we must execute woken up goals before ;/2: force stack checking at either.
- FIXED: present a single delayed goal per variable Done.
- FIXED: make block/1andwait/1directives.
- FIXED: make block/1usewhen/2.
- FIXED: compiling with glibc2.2, gcc-2.96 had small complaints.
- FIXED: configureshould now work with gmp3.
- FIXED: overflow with extremely large terms in copy_term.
- FIXED: unification between bignumscould fail.
- FIXED: improve print_message/2.
- FIXED: make number_codesunderstandinfandnan.
- FIXED: parse bigints in files.
- FIXED: one should set creep flags whenever adding goals.
- FIXED: debugging messages to stderr.
- NEW: simpler scheme for delays.
- FIXED: (mark_trail) do not mark second assignment tomavarin same choicepoint, helps 5% in mip, zilch in rkf.
- FIXED: make goal_expansionandclause_expansionlogical and multifile.
- FIXED: stackgrow()withbiginits.
- FIXED: compile bigints properly.
- FIXED: ShowCodeshould know about bigint instructions.
- FIXED: arith.yapshould understand int != bigint.
- FIXED: ==/2had bugs with attributed variables.
- FIXED: make debugger aware of woken goals.
- FIXED: bug in debugger with single update semantics dynamic clause.
- FIXED: definition of MAX_WORKSPACEhad been deleted fromalloc.c??
- FIXED: frozen/2and outputting suspended goals.
- FIXED: BlobTermAdjustwas not always defined.
- FIXED: bad memory allocation in parser.cfor _ resulted in cryptic error messages.
- FIXED: //error in CHR.
- FIXED: syntax error in initialization.
- FIXED: syntax error messages again point to the error.
- FIXED: add extra copyright info about LUM in manual.
Yap-4.3.14:
	- FIXED: gcc/solaris would not compile.
- FIXED: gc instrumentation was still giving noise.
- FIXED: bug without GMP.
- NEW: CHR manual.
Yap-4.3.13:
	- FIXED: call_residue/2.
- FIXED: ==inconfigure.in.
- NEW: document attributed variables and CLP(Q,R).
- NEW: initial support for Apple OS/X, thanks to Paulo Moura for the patch.
- FIXED: hash trouble in IDB (thanks to Stasinos Konstantinos for the report)).
- SPEEDUP: meta_predicatedatabase is now in dynamic procedures with logical updates.
- FIXED: module 0 should always be found in DB.
- FIXED: alloc space for get_numfrom trail.
- NEW: discontiguousis a valid operator.
- FIXED: gcd/2operator would break on negative numbers.
- NEW: support for GMP gnu library and longints.
- NEW: back to blobs in global.
- NEW: new implementation of arithmetic with a function per operator and no switches.
- FIXED: ##breakage in OS/X cpp (c_interface.h. thks Paulo Moura).
- NEW: new arithmetic code.
- NEW: CHR(Thanks to Thom Fruewirth).
- NEW: itemization bugs in the manual (Stasinos Konstatinos).
- NEW: add sequential/0andparallel/0directives.
- FIXED: move CodesandListstoheap_regsas these variables are in fact supposed to be shared between processes.
- FIXED: SBAshould be able to store bindings in cell.
- FIXED: PutAttandGetAttmight returnNULLinSBA.
- FIXED: unifyand friends would use uninstantiated variables.
- FIXED: only install INTERFACE_HEADERS.
- FIXED: DO_MATRAILhad reverse order underSBA.
- NEW: prolog_load_context/2.
- FIXED: allow reutilising aliases to files.
- FIXED: replace term_variablesbyvariables_in_terminpl/*.yap.
- NEW: dynamic loading support for HP-UX (Stasinos Konstantinos).
- FIXED: help info in configure.inand forgotten$(Stasinos Konstantinos).
Yap-4.3.12:
	- NEW: configure compilation process from configure.
- FIXED: save/restore should set CurrentModule.
- FIXED: InitYaamRegsshould not setCurrentModule.
- FIXED: load_dld would crash on NULL argv[0].
- FIXED: get rid of install_libraryand buildlibYap.aby default. Fix minor bugs inyaplib.
- FIXED: used TRAILto remember structure-to-structure bindings in utilpreds.c and cmppreds.c (this avoids overflow noticed by GJVNoord).
- FIXED: split yapor_on so that ! is after yapor_on. This should prevent cutting to before the root of the tree.
- FIXED: bad handling of libsinload_dl.c(fix from Stasinos Konstantopoulos).
- FIXED: free_answer_hash_chainshould untag parent pointer (Ricardo Rocha).
- FIXED: walltime would compile with cygwin (patch from gzk02612@nifty.com).
- FIXED: try_logical_predwas doing nasty things to choice-points in parallel mode.
Yap-4.3.11:
	- FIXED: read could fail and not restore the original input stream (noticed by GJ VanNoord).
- FIXED: crappy handling of multi-assignment variables while growing stacks (noticed by GJ VanNoord).
- FIXED: Bad save/restore machine registers in hppa.
- FIXED: Bad initialisation for '_' variables.
- FIXED: check null ENVindo_toggle_static_predicates_in_use, this seems to break HP-UX machines.
- FIXED: Bad default address on SGI machines.
- FIXED: Atom operations were being included too soon.
- FIXED: alignment issue in LastWTimePtrwith SPARC.
- FIXED: Bind needs HBREGinp_save_cp/exec.c.
- FIXED: small ints in term_hash.
- FIXED: bug in installing CLPQR in Makefile.in(noticed by Luis Castro and GJ VanNoord).
Yap-4.3.10:
	- FIXED: install info by default in /usr/share/info.
- NEW: MULTI_ASSIGNMENT_VARIABLESshould work with tabling and or-parallel execution.
- FIXED: small glitches with lcc.
- FIXED: walltimein parallel system.
- FIXED: zombies in ACOW.
- NEW: CLPR is now in the YAP distribution.
- NEW: sequential tabling can do stack shifting.
- NEW: sequential tabling uses standard memory management system.
- FIXED: make tracer work with tabling.
- FIXED: make exec_goalwork with tabling.
- NEW: integrated latest OPTYap.
- NEW: CIAO's pillow library.
- FIXED: verify_attributesshould follow SICStus order, or else CLPR will break incritical,go2:-(.
- FIXED: debugger was getting confused by modules that import predicates that are also defined in the module.
- FIXED: =..was messing with constraints, make itSDerefHead.
- NEW: print $VAR("string")as string.
- NEW: write_term(X,[write_depth(X)])is a legal option in SICStus.
- NEW: write_term(X,[portrayed(X)])is a legal option in SICStus.
- FIXED: debugger would get confused with undefined procedures.
- FIXED: DB compression bug for lists with rational trees on.
- FIXED: the blackboard routines are meta-predicates!
- FIXED: initialization should be performed on correct module.
- FIXED: make initialization/1an operator.
- NEW: print_messageandportray_message.
- FIXED: do proper meta-predicate processing for user:a :- meta(...).
- FIXED: do term expansion from top level and for end_of_filein consult.
- FIXED: don't do grammar expansion if term expansion succeeds.
- NEW: yap_flag(toplevel_hook,_): this is a goal to be executed before prompting at the top-level.
- NEW: variant/2.
- FIXED: term_hashwas not documented and in the wrong modules.
- NEW: first try at ugraphs module.
- NEW: SICStus compatible module/1andyap_flag(typein_module,_).
- NEW: SICStus compatible prolog_flag/2andprolog_flag/3.
- FIXED: for SICStus compatibility primitives module is now prolog module.
- FIXED: corrent consulted file could get confused.
- FIXED: more fixes to top-level and call-residue with attributed variables.
- FIXED: call to compare_termsinoptimise_cerelied on correctH. Could corrupt the compiler.
- FIXED: fix a few bugs on presenting floundered goals.
- FIXED: procedures imported into user should be imported by every module (do that by binding the importer to a variable).
- FIXED: do not try to debug over commit.
- FIXED: make top-level more SICStus like on how to present variable bindings.
- NEW: support columns in format/2andformat/3.
- FIXED: p_numberand friends should check for var before checking for number with corouting support.
- FIXED: init was setting WakeUpCode too late.
- FIXED: save_programwas not restoring WakeUpCode.
- FIXED: termslibrary.
- NEW: SICStus compatible prolog_flag/3.
- FIXED: \+ \+ nondet1, !, nondet2.
- SPEEDUP: improved exec path.
- FIXED: hold locks for longer in i_recorded.
- CLEANUP: avoid references to corouting data structures in non-corouting code.
- NEW: new hashing function for IDB.
- FIXED: make profile_dataunderstand modules.
- FIXED: first argument for profile_data was inconsistent.
- FIXED: broken trail resetting in p_read(thks G.J. VanNoord).
- CLEANUP: ANSI-C code cleanup (thks S. Konstantopoulos).
- CLEANUP: new Atom.h.m4file splits some stuff fromYatom.h.m4.
- CLEANUP: linkblkwith one less argument and faster code (hopefully).
- FIXED: get rid of AtomBase.
- FIXED: keep ordering between MkFunctorand friends.
- FIXED: PreviousHeapis trash.
- FIXED: too many calls to MkFunctorinGetPred.
Yap-4.3.9:
 	- FIXED: VC++ compilation was broken.
- FIXED: handle trail overflows in Windows.
- FIXED: general fixes as cygnus compilation was broken.
- FIXED: yap.expgot out of sync.
- FIXED: YAP would include too many headers such as sys/time.handsys/wait.hbreaking-mno-cygwin.
- FIXED: don't trust in string.hto initialiseNULL, this seems to cause weird problems ingcc -mno-cygwin.
- FIXED: lack of heap in assembler shouldn't force compiler to restart.
- FIXED: C-stack would overflow with PermVar, make this function non-recursive.
- FIXED: hint growheapon the least heap it needs.
- FIXED: expand stack on overflow while parsing and overflow while creating the var table.
- FIXED: move ParserStacktoTrailso that we can read in very large terms.
- FIXED: recursion of c_optimisewould break for very large clauses, replaced it by iteration.
- CLEANUP: replace defined for enuminYatom.h.m4.
- FIXED: bug in compiled terms with DBRefs (same field was used for CodePtrandRefPtr).
- FIXED: guarantee correct locking for PreAllocCodeSpace().
- FIXED: another typo in charsio.
- FIXED: always allow asserts but careful, for now system will only recover some space at top-level.
- FIXED: In yap.creadfalsebefore someone hides it ;-).
- CLEANUP: get rid of AtomLiveand ofAtomFalse.
- FIXED: erase/1anderased/1now complain on bad arguments.
- FIXED: ANALYST would not compile.
- FIXED: go round bad FILENAME_MAXin HPUX (Stasinos Konstantopoulos).
- CLEANUP: use sedinstead of symbolic links inmake depended(Stasinos Konstantopoulos).
- FIXED: don't check if someone is looking at an environment while asserting.
- FIXED: gc always assumed an immediate DBRef.
- FIXED: !now cuts if!=instead of<(fixed cut_by).
- FIXED: __hpux to __hpux (Stasinos Konstantopoulos).
- FIXED: makedependworks again (Stasinos Konstantopoulos).
- FIXED: compile under hpux cc (Stasinos Konstantopoulos).
- NEW: locking for internal data base.
- FIXED: bad cast in DBProp.
Yap-4.3.8:
 	- FIXED: previous change to !was wrong.
- FIXED: YAP_ARRAYSwas still being used inarrays.candsbaamiops.h.
- FIXED: small glitches in the manual.
- NEW: change work dir from Yap4 to Yap-4 (that's what everyone else does).
- NEW: make install_info.
- NEW: yap.specand automatic generation of rpms.
Yap4.3.7:
 	- FIXED: fix SBA bug in or.cuts.h.
- NEW: cut now looks for ==, not<.
- NEW: FunctorListis now special.
- FIXED: Looking up "." was broken.
- FIXED: halt/1would not send out the error code.
- NEW: allow executable Prolog files that call YAP (option -L).
- FIXED: bad overflow handling when compiling very large terms.
- FIXED: bugs in charsioatopen_chars_streamandnumber_to_chars.
- FIXED: search for library()did not use env varYAPLIBDIR.
- NEW: parallel locking for MIPS machines.
- NEW: parallel locking for Alpha machines.
- FIXED: In OPTYAP UNLOCK should be machine dependent.
- FIXED: In linux, SBA would mess up with DB because MBIT was in binding_arrayaddresses. Fix that and include a check when we allocate BA space.
- NEW: Protect DB updates and use with immediate update semantics.
- FIXED: get rid of the stuff on searching whether a predicate is in use for YAPOR, as it wouldn't work.
- FIXED: disallow asserting and abolishing static procedures in YAPOR.
- NEW: allow asserting database references as arguments for dynamic procedures.
- FIXED: consult and friends are now directives (this should avoid trouble with YAPOR).
- FIXED: change configure.infor Alpha/Linux.
- FIXED: change YAPOR not to try to do parallel execution of consult.
- FIXED: protect goals from save_program/2and also make sure they don't fail.
- FIXED: [a]in top level should be executed as a query.
- CLEANUP: get rid of c_csult_stream.
- FIXED: fix predicates that depended on current_streamreturning user name for file.
- FIXED: close/1andclose/2should only close atomic filenames in YAP mode, and should not depend on current_stream/3 returning the original name.
- FIXED: current_streamshould return real name, not user name.
- CLEANUP: add consult/reconsult mode and file name to consult stack.
- FIXED: force indexing immediately after consult in YAPOR. This guarantees the system will not get into trouble later trying to generate indexing code for a predicate while someone is entering it.
- FIXED: bad init interface with YAPOR.
- NEW: support partial locking for predicates.
- FIXED: wrong include path in regex's Makefile.in.
- FIXED: bb_newwas doing a broken property insert.
- FIXED: save_programnow restoresSpyCodeso that we can restart saved states with spying data.
- FIXED: YapInitwasn't using stack size info from saved states.
Yap4.3.6:
 	- FIXED: YapRunGoalwasn't saving/restoring registers properly, thus breaking the alpha platform.
- FIXED: could not find saved state.
- FIXED: bad substitution in saved states.
- NEW: -loption for YAP (consult a Prolog file).
- CLEANUP: -loption for YAPOR is now-sl.
- CLEANUP: small cleanups in yap.c.
Yap4.3.5:
 	- NEW: add yap_libdir.
- NEW: add splay trees.
- NEW: add AVL trees.
- FIXED: asserting static predicates would not store the right source.
- FIXED: assertwould loop withassert((H:-b)).
- FIXED: GC bug would not process direct pointers from local or trail to lists in code space.
- NEW: change directory structure.
- NEW: support locking for arrays.
- NEW: support locking for operators.
- NEW: support locking for values.
- FIXED: bad comparison with BBinwrite_val(SBA).
- NEW: support locking on alloc/free.
- NEW: support locking on blackboard.
- NEW: support locking for individual atoms (protects the property list).
- NEW: support locking the atom table.
- NEW: sequential code should now compile empty locks.
- FIXED: YAP again compiles and runs under AIX4.1.
- FIXED: support creating YAP DLL with VC++.
- FIXED: VC++ didn't understand S_ISDIR().
- FIXED: small fixes to yap.tex.
- FIXED: unsigned/sign comparison warnings in VC++.
Yap4.3.4:
 	- FIXED: IRIX6 is now set up load DLLs.
- FIXED: Yap4.3.3 had broken register handling in c_interface.c.
- FIXED: bug in library/regex/Makefile.in.
- FIXED: FreeBSD/ELF is now set up to load DLLs.
- FIXED: in_limboshould now be correct.
- FIXED: YAPOR would not compile because of macros.
Yap4.3.3:
 	- FIXED: recover space after every parse/compile in new yap.c.
- FIXED: ignore getcwdunder simplescalar.
- FIXED: only include standard files after YAP headers.
- FIXED: save and restore registers correctly under c-interface.
- NEW: add YapWriteto C-Interface.
- FIXED: mmapped arrays do not compile with simplescalar.
- FIXED: force saved states to look up YAP in YAPBINDIR.
- FIXED: quoted strings go back to ISO.
- FIXED: -DYAP_ARRAYSis no longer an option.
- FIXED: get rid of a few of ANSI-C old-style warnings from lcc.
- FIXED: TrueFileNamehad been broken.
- FIXED: Yap now configures and compiles with lcc 4.1/Linux.
- FIXED: port yap to compile under cygwin 1.1.0/mingw32 and to support winsock2. The new version also supports CreateWaitableTimer.
- FIXED: force yap to follow environment variable YAPLIBDIR.
- FIXED: force yap to look for dlls in library.
- FIXED: replace strcatandstrcpybystrncatandstrncpy.
- FIXED: search for saved states in library.
- FIXED: ^c-ain MINGW32.
- CLEANUP: ^Chandling.
- NEW: creating and loading dll now works in YAP/WIN.
- NEW: compile core YAP as a dll under MINGW32.
- NEW: yap.cis now external to YAP.
- NEW: understand Unix paths under WIN32 and MINGW32.
- FIXED: make sure you only start compiling objects after having all headers ready.
- FIXED: Debugger ($spycalls) should module switches and consulted the table of imported predicates.
- FIXED: Compilation bug and warnings under vc++.
- FIXED: YAP_ARRAYSrequiredTERM_EXTENSIONSto compile.
- FIXED: compile under cygwin's gcc -mno-cygwin, so that YAP won't need the cygwin dll (MINGW32).
- FIXED: save.cshould reinitialise user streams.
- FIXED: predentriesfor functions may change address insave.c.
- FIXED: SimpleSimdoes not implementgetcwd.
- FIXED: tracer.chad a C++ comment.
- FIXED: ttynamemight returnNULL, at least inSimpleSim.
- FIXED: reconsultwas broken.
- FIXED: bracket messages for syntax errors.
- FIXED: scanner would break if AllocScannerSpacefailed.
- FIXED: bad checking of eof_actionin open.
- FIXED: mistake in compiling /\.
- FIXED: extra clauses in environ.
- FIXED: checking list of operators was wrong in op/3.
- FIXED: missing variable in error message.
- FIXED: reset CreepFlaginError.
- FIXED: wrong error in name(int(X),_).
- FIXED: fix writing "\" when writing strings with no character escapes.
- NEW: add yap_flag(write_strings,X)as in Ciao.
- NEW: add StringToBufferroutine to the c-interface.
- NEW: add routines for allocating and releasing database space to the c-interface.
- FIXED: change type for unifyinCInterface.
- FIXED: PlUnGetcshould returnint, notInt.
- FIXED: get rid of C++ comment in save.c.
Yap4.3.2:
 	- FIXED: Yap can now use shmfor memory allocation.
- NEW: Yap can use mallocifmmap,shm, andsbrkfailed.
- FIXED: sbrkallocation should be working again.
- CLEANUP: get rid of unused functions in old alloc.c.
- CLEANUP: in Yap.h.m4make clear when you are in second quadrant.
- CLEANUP: keep table with all c-predicates. restorenow does not need to reinitialise functions.
- FIXED: in alloc.c, handle cases where/dev/zerofails properly.
- CLEANUP: move atoms and functors into heap_codes.
- CLEANUP: move module info to heap_codes.
- FIXED: save.cwould not restore properlybfuncinstructions. Had to add a p field for these instructions.
- FIXED: save.cwas not always restoringpp->OpcodeOfPred.
- FIXED: reset opcode-op hash-table in new calls to InitReverseLookupOpcode.
- FIXED: check if emulator shifted when recovering saved states.
- NEW: charsio, SICStus compatible reading to and writing from strings.
- FIXED: uncaught instantiation errors in eval routines.
- NEW: yap_flag(character_escapes,{on,off}).
- CLEANUP: get rid of config.c.
Yap4.3.1:
 	- FIXED: $calland$spied_callused with one less argument by debugger.
- FIXED: bug in repeatfrom top level.
- FIXED: MAX_DEPTHwas set too high.
- FIXED: use actual definition of repeat.
- FIXED: use <to compare cps for!, not==because of(! ->).
- FIXED: $set_depth_limitshould work with Integer, not Int.
- FIXED: Allow Linux to compile without getrusagebut using times (problem with glibc/kernel).
Yap4.3.0 has been released.
Changes in YAP4.2
Yap4.2.1:
 	- FIXED: up release number.
- FIXED: swap order of first authors in the manual.
- NEW: more patches for OPTYap.
- FIXED: not all Linuxen that have fpu_control.hunderstand_FPU_SETCW.
Yap4.2.0pl18:
 	- FIXED: DebugPutc.
- FIXED: SBA must initialise or set public permanent variables in the SBA.
- FIXED: get rid of a Prolog definition for number_codes.
- FIXED: YOUNGERout of OPTYap and renamedYOUNGER_CP.
- FIXED: don't use offsets to local in SBA.
- FIXED: make DelayedBandTopBactual choicepointers to support SBA.
- FIXED: memory allocation for FreeBSD.
- RW Locks are now in YAP (unused yet).
- FIXED: dynamic arrays were getting too complex, allow the heap to point to the global stack and change garbage collector to handle it. YAP_ARRAYS is now compatible with everything ;-) and can stop being an option.
- FIXED: cut used <instead of!=.
- NEW: new YapOr code from Ricardo.
- FIXED: a few complaints with Solaris.
- NEW: generate exceptions in ISO mode for HP-UX.
- FIXED: use_modulerelies onensure_loaded, which is now a directive.
- FIXED: 64/32 bit errors in Alpha.
- FIXED: SEG_SIZEis pre-defined in HP platform.
- FIXED: should call Erroronly after leaving interrupt handler, otherwisesigsetjmpwill overwrite registers.
- FIXED: fill CharConversionTablewith null chars.
- FIXED: warning in PowerPCs.
Yap4.2.0pl17:
 	- FIXED: more improvements to Eval.
- NEW: predicate_property(X,public).
- NEW: public/1directive, handling of source was cleaned up (it used to be broken if one would switch between source and no-source).
- NEW: special meta-call handling for ISO mode. Reduce amount of testing for other cases.
- CLEANUP: complete cleanup of eval. No more duplicate code, no moreregandfli.
- SPEEDUP: move get_spy_creeptoyap_flags. This speeds up execute a bit.
- NEW: strict_isomode.
- CLEANUP: InitEval.
- FIXED: arithmetic should be consistent even after an error.
- NEW: implement ISO exception handling for operations between floating-point numbers in Linux.
- NEW: handle floating point exceptions.
- CLEANUP: get rid of EQUAL_FLOATSandEQUAL_LONG_INTSas they weren't used any longer (and they were wrong anyway).
- NEW: add e, I've always liked this constant better thanpi.
- FIXED: get a better pi.
- FIXED: fix roundand friends for ISO mode.
- NEW: add xor(#) andsign.
- FIXED: get rid of finite, change integer the limits in YAP.
- FIXED: define atanhand friends for VC++ environments.
- FIXED: Get PlGetChar()back in, as users may want a simple interface to the current input for their own dubious purposes.
- NEW: yap_flag(discontiguous_warnings, single_var_warnings, redefine_warnings)as in SICStus. This should eventually replace style_check and no_style_check.
- FIXED: do not mark or sweep environments twice. This fixes Bart's YAP GC performance bug (as mentioned in comp.lang.prolog!).
- NEW: do variable shunting, not that it helps very much.
- FIXED: save should only save as many registers as it needs, and the ones it does should be adjusted when restoring.
- NEW: stream_select/3.
- NEW: save/2.
- NEW: char_conversion/2andcurrent_char_conversion. Add ISOGetc for this, change scanner for having two getcs (one within strings, the other elsewhere).
- FIXED: was recording source for optimised clauses, not just source for module preprocessed clause.
- CLEANUP: add specialised versions to PlGetc(): Sockets, EOF, Readline, and Console.
- CLEANUP: got rid of PlGetChar().
- CLEANUP: replaced PlPutc()by specialised versions for each type of stream: File, Console, Socket, Socket+Console, and Null.
- CLEANUP: got rid of PlPutChar().
- FIXED: ISO compatible mode for floorand friends.
- FIXED: YAP would crash with INTEGER mod 0.
- FIXED: miscellaneous error handling in eval.
- FIXED: number_charsand friends should be compatible with scanner.
- FIXED: stream_propertyshould not work with aliases.
- NEW: char_code/2.
- FIXED: ISO mode activates fileerrors.
- FIXED: avoid using atom_charswithin the system.
- FIXED: number_chars(X,I)andnumber_codes/2with bad I should give error in ISO mode.
- FIXED: make ISO abolish/1succeed for undefined procedures.
- FIXED: number_charsandatom_charsshould be ISO compatible in ISO mode.
- FIXED: errors in callshould throw ISO errors.
- FIXED: functor/3should now have standard ISO behaviour on errors.
- FIXED: assert(X)would loop.
- FIXED: char_conversion/2is now also a directive.
- FIXED: ensure_loaded/1should be directive and not a built-in.
- FIXED: current_predicate/1should not show system predicates and should be module aware.
- FIXED: utilpred.snow compiles with-DEUROTRA.
- FIXED: abolish/1had several nasty bugs, especially in ISO mode.
- CLEANUP: got rid of nasty config.cachein main directory.
- FIXED: op/3andset_prolog_flag/2are directives.
Yap4.2.0pl16:
 	- FIXED: retractallwas broken.
Yap4.2.0pl15:
 	- FIXED: in catch/3set module to original module before handling a ball.
- SPEEDUP: improve testing with DEPTH_LIMIT.
- FIXED: DEPTH_LIMITshould only stop code running underdepth_bound_call/2.
- FIXED: bug in parse_args (fix from  Stasinos Konstantopoulos <konstant@let.rug.nl>).
- FIXED: copy_term/2should now be able to copy constraints.
- FIXED: faster version of copy_term/2should now handle rational trees.
- NEW: generate ps version of manual with make ps.
- FIXED: disable save term optimisation for extensions, as we may not have an S ready.
- CLEANUP: always use '$execute' instead of call internally.
- CLEANUP: get rid of '$user_call' as it should the same as '$execute'.
- NEW: separate between the standard catch, that uses the full meta-call, and a system catch, that uses $execute0and$mod_switchand that should be only used deep within the bowels of the system.
- FIXED: expanded head variables of meta_predicates should not be expanded by inner meta-calls.
- FIXED: HAVE_STATwas not being generated correctly byautoconf.
- NEW: timeout:time_out.
- FIXED: make sure catch handlers are processed from within user.
- FIXED: processing of style_check by yap_flag(language,_).
- FIXED: discontiguousshould now be module aware.
- FIXED: preprocess calls for meta-predicates from top-level.
- FIXED: simplify code that handles the fact that modules from primitives can be called from anywhere.
- FIXED: $module_expansioncould be called with wrong number of arguments.
- FIXED: separate '$execute', the low-level mechanism for meta-call, from '$user_call', that must study meta-predicates.
- FIXED: README.VC.
Yap4.2.0pl14:
 	- FIXED: allow big flags.
- FIXED: typos in yap.tex.
- NEW: yap_flag(host_type,X), whereXcomes fromconfigure.
- NEW: more cleanups for autoconf.
- FIXED: more cleanups for autoconf.
- NEW: use -DBP_FREEby default for X86 machines.
- FIXED: make predicate_propertymore SICStus Prolog compatible.
- NEW: language mode now changes action over dynamic and over directives.
- NEW: initial DLL support for WIN32.
- FIXED: optimise arithmetic for asserted clauses.
- FIXED: calling garbage collector from within a C-backtrackable built-in should also have the extra arguments to the choice-point ready.
- NEW: YAP should now be able to load DLLs in WIN32.
- FIXED: YAP will now stop creeping after an abort.
- FIXED: meta-call within the debugger was externally visible.
- FIXED: small ANSI-C compatibility thingies.
- FIXED: writeq('aaa===\\''====')now outputs properly.
- NEW: yap_flags(update_semantics,logical_assert)if you only want to use logical update semantics for asserted code.
- NEW: yap_flags(language,{cprolog,sicstus,iso}).
- FIXED: do not test for worken goals before !, it slows down execution too much.
- NEW: improve the performance of ==/2.
- FIXED: compile without COROUTINING.
- FIXED: manual would not compile.
Yap4.2.0pl13:
 	- FIXED: term_expansionshould be called in user module.
- FIXED: include new operation sderef_opwhen we want to know what a constrained variable is bound to.
- FIXED: try_logical_preddepended onB, butBmight have been cut. Use trail for the moment.
- FIXED: call of project_attributes.
- NEW: blackboard routines bb_get,bb_put,bb_delete,bb_update, andyap_flag(n_of_integer_keys_in_bb,INT). Includes a new file, bb.c.
- NEW: yap_flag(n_of_integer_keys_in_db,INT): dynamically set the number of entries for the hash table used in looking up integer keys for the data-base.
Yap4.2.0pl12:
 	- NEW: README.VCfor VisualC++ users.
- FIXED: several small changes for VisualC++.
- FIXED: _WIN32requiresLOWTAGS(0x3000000kind of address) for garbage collection to work.
- FIXED: UnifyBoundwas not handling extensions right.
- FIXED: had wrong definition for non-gcc EXTRA_CBACK_ARG.
- FIXED: make Yap compile under VisualC++ 6.0 again.
- FIXED: exit_yapwould not exit.
Yap4.2.0pl11:
 	- FIXED: multifilewas not complaining on missing declaration.
- FIXED: multifile declarations were not module aware.
- CLEANUP: assert/1anddynamic/1.
- FIXED: for the nth time tried to make modules SICStus compatible :-(.
- NEW: integrated latest version of YAPOR (SBA and ACOW still do not work).
Yap4.2.0pl10:
 	- FIXED: could have a bad cut in call(X->Y).
- FIXED: add ord_intersect/3again (same asord_intersection/3).
- FIXED: save_program/2would not set prompt correctly.
- FIXED: bug in stack_shifteraftergc(was shifting global pointers).
- FIXED: save/1was broken with coroutining.
- FIXED: use_module/2should handle lists of files.
- FIXED: COROUTININGdepended onDEBUGcode.
Yap4.2.0pl9:
 	- FIXED: list_to_assoc/2.
- FIXED: ANALYST should compile again.
- FIXED: ensure_loadedanduse_moduleare not directives!
- FIXED: bug in cleaning up for logical update semantics.
- FIXED: cuts will now call suspended goals.
- FIXED: debugger should now step through meta-predicates correctly.
- FIXED: trust_logical_preddid not release trail entry correctly.
- FIXED: recordedpmight be create a new key in a different mode from the one used to create the dynamic procedure.
- FIXED: don't go through $undefpfor dynamic procedures.
- FIXED: bugs in asserting dynamic procedures from compiled clauses.
- FIXED: buglets with multifile/1.
- FIXED: do not open directories except as binary files.
- NEW: library random.
- NEW: assoc now has ord_list_to_assoc/2andget_assoc/5.
- NEW: compatibility module terms for term_utils.
- NEW: ordsetsnow hasord_union/4andord_del_element/3.
- NEW: add public/1directive but currently this does nothing.
- FIXED: be more precise about which files you have consulted.
- FIXED: use_module/2should not handle lists of files.
- FIXED: compare would stop whenever it would find two numbers, even if they were equal.
- NEW: attributed variables.
- FIXED: coroutining would break \=/2.
- NEW: ord_add_element/1inordsets.
- NEW: empty_assoc/1inassoc_lists.
- CLEANUP: compile under lcc4.1/Linux.
- FIXED: storing compressed rational trees on DB was buggy.
- FIXED: $unknown(_:_)should not give an error.
- FIXED: ord_intersect/3now isord_intersection/3.
- FIXED: recursive do_goalwould corrupt coroutining information.
- FIXED: handle possible overflows in quoted strings.
- CLEANUP: move .pllibrary files to.yap.
- CLEANUP: get rid of unused SusRecTopandSusRecBase.
- CLEANUP: move HeapUsed,HeapMax, andHeapToptoHeap.
- FIXED: add MMAP_ADDRfor WIN32.
Yap4.2.0pl8:
 	- NEW: user:goal_expansion/3.
- SPEEDUP: use separate table for integer keys to data base. Table size can be configured with -DMAX_DB_INT_KEYS=.
- SPEEDUP: increase the size of HashTable, which was ridiculously small.
- CLEANUP: allocate heap_regsas heap start.
- SPEEDUP: avoid calculation for compile-time keys.
- NEW: get_float.
- NEW: change the way functors of processed.
- CLEANUP: got rid of disgusting GeneralRef type, it has been replaced by Integer.
- FIXED: unknown_errorshould not complain ifprintis called with undefined portray.
- FIXED: delay cuts that go through embeddeded c-calls. This requires two extra registers, DelayedBandTopB.
- CLEANUP: LockPredwasn't being used any longer.
- FIXED: fact for truewas not being asserted.
- NEW: now long ints and floats are tagged.
- FIXED: array/2was a safe predicate that could callgc().
- FIXED: growstackincclauseshould also callgc().
Yap4.2.0pl7:
 	- FIXED: 8 bit characters would be mangled by char->Int conversion in StringToList.
- NEW: Garbage collection should now work for a total space of 1GB on second quadrant (use low_tags).
- FIXED: ExtendWorkSpacewould not always guarantee aligned size.
- NEW: call_with_args/n, meta-call with variable arity (up to 10).
- FIXED: array/2overflow had not been fixed properly.
- FIXED: sortand friends would not handle overflow properly.
- FIXED: improve manual include small bugs, compatibility stuff.
- SPEEDUP: replace opcode(_index_pred)withINDEX_OPCODE.
- SPEEDUP: replace opcode(_undef_p)withUNDEF_OPCODE.
- FIXED: only optimise common_expressions up to level 5.
Yap4.2.0pl6:
 	- FIXED: coroutining had been broken when initialisation was reordered.
- ISO: predicate_propertyof static predicates now returnsstatic, instead ofcompiled.
- FIXED: if format/2~s would complain for empty strings.
- FIXED: bug with too large arrays.
- NEW: term_hash/2andterm_hash/4.
- FIXED: allow modules in bodies of DCGs.
- FIXED: get rid of modules in head before they hit DCGs.
- FIXED: current_predicatewith modules.
- FIXED: $undefined/1should never collapse.
- FIXED: listingwould collapse because of:/2.:/2is not an undefined procedure now.
- FIXED: in saved states replace $*by "$@".
- NEW: user:unknown_predicate_handler/3from SICStus.
- FIXED: declare findall/4a meta_predicate.
- FIXED: switch third and fourth argument to findall/4to obtain SICStus compatibility.
- FIXED: unknown/2should know about modules.
- FIXED: speedup handling of unknown predicates in meta-calls.
- FIXED: speedup depth_bound_call(A,D)by using$execute.
- FIXED: add chapter on modules to manual.
- FIXED: meta_predicates from same module were not being expanded.
- FIXED: modules use current module for meta predicate.
- REVERSE: default meta_predicates back to user.
Yap4.2.0pl5:
 	- FIXED: meta_predicateshould be a directive, not a standard predicate.
- FIXED: all default meta_predicates should belong to user, not primitives.
- FIXED: give errors when not finding libraries.
- FIXED: load_module/1andload_module/2are now directives.
- FIXED: load_module/2would not accept libraries and had bad error handling.
- FIXED: catch/3did not have a meta_predicate declaration.
- FIXED: meta predicates were not being expanded correctly.
- FIXED: saved state script was not passing arguments to Yap.
- FIXED: go around gcc bug in current_opfor hpux machines.
- FIXED: top level abort would crash in hp machines (TRwas overwritten).
- FIXED: error messages for op/3.
- FIXED: ord_member/2inordsets.
Yap4.2.0pl4:
 	- NEW: the evil recordaifnot/3andrecordzifnot/3are now in the manual.
- FIXED: include ord_union/2andord_member/2inordsets.
- FIXED: complain about _:G.
- FIXED: allow modules in heads for assertand friends.
- FIXED: allow modules in multifile and dynamic declarations.
- FIXED: send error messages in modules.yaptouser_error.
- FIXED: get rid of error message in eraseall.
- NEW: term_variables/2.
- FIXED: directives had broken ensure_loaded/1foruse_module/1.
- NEW: small performance improvements in unification routines (UnifyGlobalCells).
Yap4.2.0pl3:
 	- FIXED: small performance improvements in unification routines.
- FIXED: logical_update semantics were broken in pl2.
- FIXED: findalland friends were broken in pl2.
- FIXED: bind_globalwithinunify_struct.
Yap4.2.0pl2:
 	- NEW: static arrays of DB terms.
- NEW: close_static_arrayandresize_static_arraynow work over mmapped files.
- FIXED: rename delete_static_arraytoclose_static_array.
- FIXED: improve the manual a little bit. Add info in README to Manual.
- FIXED: support for ISO-style atom_chars/2andnumber_chars/2.
- NEW: ISO include/1directive.
- ISO: ensure_loaded/1is now a directive (and it cannot be called as a procedure).
- NEW: discontiguous/1directive.
- NEW: process multifile/1as a directive.
- FIXED: give warning if multifile procedures are used before multifile declaration.
- FIXED: multifilewas very severy broken.
- FIXED: initialize/1now follows ANSI semantics. We haveprolog_initialize/1for SICStus Prolog code.
- FIXED: don't explode if the compiler finds too many variables or if there is not enough code space to store our code.
- NEW: ISO quoted character sequences (note that this means that '\+' will break now).
- FIXED: remove limit on size of strings and quoted atoms.
- FIXED: [    ]is now parsed as[], like other Prologs do.
- FIXED: read-in clauses predicated by modules (mod:clause).
- FIXED: gcc/HP-UX would generate incorrect code for PredForCode. Use an extra temporary (at) and the probably goes away.
- NEW: add "make install-info", "make info" and "make html".
- FIXED: create a README file mentioning the license, get rid of the INSTALL file for now.
- FIXED: don't shadow S,CP,HBin hppa. They have their own registers.
- FIXED: change x86 back to base address 0x10000000andtagsback toopstagsfor Linux.
Yap4.2.0pl1:
	- FIXED: works(?) in HP/UX.
- NEW: update_arrayfor dynamic arrays.
- FIXED: works in FreeBSD.
- FIXED: improvements and additions to configuration scripts.
- NEW: port to Visual C++ (_MSC_VER).
- NEW: major improvements and bug fixes to YAPOR.
- CLEANUP: _REGto_.
- NEW: arrays of bytes and of unsigned bytes.
- FIXED: worked a bit on manual.
- NEW: resize_static_array/3.
- NEW: delete_static_array/1.
- FIXED: ACOW in YAPOR.
- FIXED: Error after Error would not notice there was no place to cut back to.
- FIXED: SBA in YAPOR.
- NEW: version/0andversion/1. Deletedyap_version/1.
- NEW: is_mutable/1.
- FIXED: recent bug in dif.
- SYNCH: with Ricardo Rocha's optyap. SBA is broken.
- FIXED: reverse_opcode_lookuptable.
- NEW: YAP as a library:
	
   		- New functions provide an interface for initialising and calling Yap from external environments. Note that Yap is still a big chunk.
- Restoring embedded C-functions is now performed by restore_heaptogether withInitStaff.
- The code to restore a clause has been updated to use yamopandGONEXT. The same code does both indices and clauses.
- All macros that adjust pointers are now functions, and type-check their arguments.
- All functions that restore a stack (from restore, growheapandgrowlocal) have now been merged in a general function ingrow.c. This decreases efficiency slightly, but should improve maintainability.
- InitStaff()now has an argument saying whether we are calling from boot or from restore. Note that most Prolog executions will actually call- InitStaff()twice.
- initialisation code in yap.cwas simplified. Several functions and variables were moved out toinit.c.
- routines that start new goals were moved out of cdmgr.ctoexec.c.
 
- FIXED: all clauses should terminate with _Ystop, but we just didemit_opinstead ofa_e.
- NEW: save_program/2.
- NEW: save_program/1. Default startup is now throughsave_program.
- FIXED: breakshould not remove choice-points.
- FIXED: allow (call(X), X)to possibly succeed. It is unclear whether that conforms to the ISO standard, but there is the excuse it is SICStus compatible.
- FIXED: $undefpwould call a bad$user_call.
- FIXED: bad calculations for walltime.
- FIXED: bug with depth_bound_callfornotand\+.
- FIXED: execute_goalwould not recover registers correctly.
- NEW: SICStus compatibility predicates including incore/1,callable/1, andsimple/1.
- NEW: add arity as an extra argument to _structfunctions.
- FIXED: uninitialised profiling counters.
- FIXED: OPTYap had broken unknown=error.
- FIXED: small bug in assembling index code.
- FIXED: growheapwould not fix trail properly.
- NEW: logical update semantics for internal data-base.
- CLEANUP: indexed code also has a tag.
- FIXED: putenv/2must allocate static memory.
- FIXED: remove duplicate clauses in environ/2.
Yap4.2.0:
	- NEW: YAP4.2.0 is out.
- REMOVED: file RELEASE.NOTES.
Changes in YAP4.1
Yap4.1.19:
	- FIXED: phrase/3had bad call to$t_body.
- FIXED: warnings on alpha.
- FIXED: make YAP compile on SGI's cc.
- ISO-YAP: accept 0onotation for octal integers.
- FIXED: rcdifnotwould try to unify withNULLreturn pointer.
- FIXED: when/3did not link Done variables.
- FIXED: bad copying of arguments in co-routining.
- NEW: first cut at SBA or-parallel execution.
- FIXED: YAP version is now in Makefile.
- NEW:  alarm/3(see manual).
- FIXED: errnohandling is inio.h.
Yap4.1.18:
	- FIXED: debugger would not work after change to call.
- FIXED: do not trace !Gwithin debugger.
Yap4.1.17:
	- FIXED: error handler for floats was too enthusiastic in format/3.
- FIXED: accept list of dynamic predicates.
- NEW: merge new version of Ricardo Rocha's OPTYAP including support for tabulation.
- NEW: improve performance of call.
- FIXED: trail overflow in heap gc (store_ref_in_dbtable).
- FIXED: close fdifmmapfails.
- FIXED: IsPrimitiveTermwould succeed on suspended variables.
- FIXED: small bug in socket_select.
- FIXED: garbage collector would follow old values of multi-assignment variables even if they were not heap pointers.
- FIXED: garbage collector was following list of suspended goals as if a variable.
- FIXED: call/1was not importing modules correctly.
- NEW: A library. Right now it just consists of several files copied from the Edinburg Prolog library, with little or no change. To use it, you must do "make install" or haveLIBDIRin the Makefile set to the YAP source directory.
- FIXED: garbage in debugger.
- FIXED: fix writing \+ (a,b)properly.
- NEW: get rid of addresses for the unify()routines. Unify now receives values, as it should, instead of addresses.
- NEW: get rid of the representant stuff for coroutining. Instead of trying to find out if we bound an external variable, from now on we must guarantee that we pass a non-dereferenced external variable (e.g. argument) to the unification routine, otherwise delayed variables may not wake up.
- FIXED: get rid of bind_variable.
- FIXED: exit_yapwas not working (halt).
- FIXED: write version number when booting from a saved state.
Yap4.1.16:
	- FIXED: don't crash if you're not booting from the standard file (SavedInfoshould not assumeLookupAtomworks).
- FIXED: prompt (again).
- FIXED: debugging dynamic or source mode procedures would ignore depth limits.
- FIXED: -DBP_FREEcould lose program counter, if changed byErClorErDBE.
- FIXED: global registers could be smashed by the compiler within error handlers (SGI).
- FIXED: fix a bug on and thus enable garbage collection of code space.
- FIXED: bug in cut_by_y.
- FIXED: be less optimistic about when to expand the trail after a sigsegv.
Yap4.1.15:
	- FIXED: disable garbage collection of code space.
- FIXED: growstackdid not knowOldH.
- FIXED: be conservative about new variables in branches (active_branch).
- NEW: change code to Artistic license.
- FIXED: include errno.hin socket code.
- FIXED: strcpyofNULLpointers insysbits.c.
- FIXED: writing \+ (a,b)would not output middle space, confusing the parser.
- NEW: initial support for the SBA model (parallelism).
- FIXED: make the system more robust when it can't get more memory.
- FIXED: recordedwith unbounded key was crashing.
- CLEANUP: use derefawhen we know the possible address for a variable. This avoids reading a memory cell twice.
- CLEANUP: make sockets a special stream, make actual reading and writing on sockets work, unify all close operations on sockets, update iopreds to take special care of sockets. Still not working: ungetc on sockets, eof has not been tested.
- CLEANUP: conditions on c-interface.
- FIXED: growheap could be called with wrong local stack pointer.
- NEW: always_prompt_user/0, for those who hide behind pipes and sockets.
- FIXED: bug in frozen/2and friends.
- CLEANUP: use Prolog terms in coroutining, avoid NULLpointers.
- FIXED: save/restore was breaking corouting.
- FIXED: readlinedoes not work under parallel execution.
- CLEANUP: cleanup some constructs so that YAP will compile under lccagain.
- CLEANUP: follow choicepoint ordering whenever possible.
- FIXED: incorrect detection of overflows in index.c.
Yap4.1.14:
	- FIXED: texi2dvifailed on the manual because of incorrect placement of@*.
- FIXED: RECOVER_MACHINE_REGSfor MIPS inRegs.hhad somehow lost anE!
- FIXED: expand stacks if effectiveness of garbage collection is below 20%.
- FIXED: YAP was not checking for excessive number of labels while assembling.
- FIXED: get rid of noin sequential init.
- FIXED: bug in checking modules for abolishand friends.
- FIXED: with readline, prompt even ifstderris not atty. Also make sure prompt goes tostderr, not tostdout.
- NEW: SICStus Prolog compatible socket interface (see manual, still experimental).
Yap4.1.13:
	- FIXED: Cygnus getrusagedoes not work under WIN95.
- FIXED: extraneous pushin compilingbvmapfor either.
- FIXED: long printf in heapgc.c.
- FIXED: extraneous printfindbase.c.
- NEW: sync until leftmost in YAPOR.
- NEW: sequential predicates in YAPOR.
- FIXED: YAPOR in OPTYap now runs queens.
Yap4.1.12:
	- FIXED: make sure that when you backtrack to an erased clause you don't get caught by dangling pointers.
- FIXED: check args to arithmetic comparisons are not free.
- FIXED: make sure you only mark an env var as initialised if the instruction refers it for the first time.
- FIXED: Error handler depended on pointer to freed code.
- FIXED: always fully gc clean the last environment.
- FIXED: new dbref gc cleaner could mess with dbqueues.
- FIXED: test if YAP can allocate more memory.
- FIXED: YAP now makes procedures dynamic after first assert.
- FIXED: because of disjunctions, variables in clauses do not always grow linearly. Change compiler to informe gc of actual live variables in an environment at any point, not including variables outside the current branch (even if at ancestor's branches). Take special care with optimised if-then-elses.
- NEW: speedup compact_heap.
- FIXED: CheckDBOverflowinMkDBTermwould not reset variables, as it should.
- FIXED: recover HBin gc.
- NEW: Integer macros for integers that may overflow.
- NEW: jump across unmarked cells in downward pass.
- NEW: simplify marking longints and doubles.
- NEW: small performance improvement in meta-call.
- FIXED: make toggle preds robust to meta-calls.
- FIXED: bad error handling in evaluable predicates.
- NEW: upgrade YAPOR to most recent OPTYAP.
- CLEANUP: use the RESET_VARIABLEmacro to reset a variable.
- FIXED: ITERATIVE_DEEPENINGoption is now calledDEPTH_LIMIT.
- NEW: simplified autoconf script and Makefile.
- FIXED: YAPOR now compiles again and reaches top-level.
- CLEANUP: make assembly built-ins accessible as standard predicates. This makes meta-calls somewhat less bulky.
- FIXED: YAP could crash while reading in binary files. The problem was that the hash function could return an offset < 0.
- NEW: in GC check if db terms are in use, and if not reset counters. Further reclaim immediately space for terms erased and not in use (current implementation uses an inefficient unbalanced binary tree).
- NEW: in GC untrail unmarked bindings and reset the pointers.
Yap4.1.11:
	- NEW: after several requests, added assert_staticand friends.
- FIXED: bug in adding spaces while writing X is $VAR(2)+...
- NEW: stream aliases.
- FIXED: ^C-anow works onPUSH_REGS(eg, X86).
- FIXED: catchcould remove other valid catches.
- FIXED: several cases of non-compatible ISO error handling.
- FIXED: current_inputandcurrent_outputwould fail for instantiated arguments.
- FIXED: writing $VAR(X)terms could core dump miserably.
- FIXED: initialisation was not protected by a catch/3.
- FIXED: system would exit after trying to compile Numeric or DBRef goal.
- NEW: improve performance of arithmetic comparisons by inserting them as ops in abstract machine.
- FIXED: meta-call would get lost in call((X,Y)). Callable checking is now ISO (almost).
- FIXED: recursive compare was not catching term_extson second argument to comparison.
- FIXED: compilation warning on printing Int in alpha.
- FIXED: gc would mark terms accessible only from the trail. Change so that these pointers are only relocated, and remove dangling pointers from the trail.
Yap4.1.10:
	- FIXED: get rid of ExecutePrologas used byprint/1, execute_goal can do the same.
- FIXED: execute_goalshould survive garbage collection and/or stack shifting.
- FIXED: $undefinedsucceeded for predicates written in assembly.
- FIXED: provide 16 registers (ARG1toARG16).
- FIXED: some changes to make YAP work without ALIGN_LONGS.
- FIXED: old timing bug.
- FIXED: bug in generating cut.
- FIXED: don't crash if have several errors on the same expression.
- FIXED: use strerrorinstead ofsys_errlist.
- FIXED: make system more resilient to small ints.
- FIXED: system should be more resilient when allocating large chunks of memory.
- FIXED: X is cputimeshould have no rounding problems.
- FIXED: silently fail on wrong array accesses.
- FIXED: truewas not seen as built-in.
- FIXED: DEPTHwas not always saved correctly inexecute_prolog.
Yap4.1.9:
	- FIXED: bug in scanner.
- FIXED: bug in allocating large chunks of memory under NT, and change to allow YAP to at least run under WIN95/98 (memory allocation and timing are not working yet for WIN98).
Yap4.1.8:
	- FIXED: random would only work in Linux.
- FIXED: better names for array_element/3andupdate_array/3.
- FIXED: array access now does boundary checking, and fails if you try to access an undefined reference.
- NEW: profiling now counts calls to non-profiled predicates, included system built-ins.
- FIXED: profiling now does not need to disable indexing.
- FIXED: predicate_propertywas returning just the name for unbound calls.
- NEW: putenv/2. If you want to start shell scripts.
- NEW: YAP now supports 8 bits char sets. The default is iso-latin.
- NEW: call_residue/2now available.
- FIXED: serious bug in can_unify:HBwas not set toH. Should be no problem withB.
- FIXED: trim_trailis not compatible with Multi-Assignment variables.
- FIXED: under a few cases code could have problems if some was using a dynamic clause and retracted it.
- NEW: improve absmi for coroutining.
- FIXED: bug in statistics(runtime,T).
- NEW: statics(walltime,T)and internalwalltime()function.
- FIXED: changed code that assumed dir_separatorcould only be a single character. Some MS-DOS systems accept both slash and backslash.
- FIXED: for compatibility with other Prologs, YAP now changes directory to the directory containing the file it is consulting. Don't need to create an init.yapany longer.
- NEW: getcwd/1.
- FIXED: disallow integer as argument to cd/1and friends.
- FIXED: randshould depend onMAX_RAND; documentsrandom.
- NEW: environnow allows access to a process' environment.
Yap4.1.7:
	- FIXED: bug in read_term/singletons. I incorrectly assumed variables were being allocated in order.
- FIXED: too much space was being allocated for 64 bit architectures.
- FIXED: error handling in data base could collapse.
- FIXED: ASPforgrowheapcould be wrong.
- FIXED: growheapandgrowstackforgot about dangling pointers in the trail.
- FIXED: increase margins as garbage collections happens.
- FIXED: make recordedand friends restartable for the case there is no space left to copy the new term.
- FIXED: make memory allocation routine more generic, try to use temporary files when /dev/zerois not available, control whether we are fetching the right addresses, and close open mmaped stream.
- FIXED: make sure we always have an error handler in the debugger.
- FIXED: GC should now work with named dynamic arrays and array extensions. Access to named dynamic arrays now goes through the trail.
- FIXED: make arg/3silently fail on negative or 0 first arguments. Breaks the ISO standard, but seems to be compatible with other Prologs.
- FIXED: dequeue could leave dangling pointers to the data-base.
- FIXED: bad error handling in arithmetic built-ins.
- FIXED: absolute_file_name/2was buggy.
- NEW: extend C-interface to allow calling back Prolog.
- FIXED: moved to version 98.
- FIXED: variable ppcwas causing trouble with Rhapsody.
- FIXED: GC should now work with coroutining.
- FIXED: coroutining had bug with reference chains.
- FIXED: error handler called unexisting procedure $close/2.
- FIXED: small bug in unknown/2.
- CLEANUP: improve meta-call performance by avoiding unnecessary choice-points.
- FIXED: assert and source mode are now aware that modules call meta-calls.
- FIXED: libraries should be checked for existence before checking for the files themselves.
- NEW: dynamic loader now works in Linux/Alpha and in Digital Unix/Alpha! Fixed bugs where YAP would corrupt global variables allocated by external functions.
- FIXED: BP_FREEdidn't do callee save forPREG, possibly corrupting the caller. Core dumpedprint/1on X86.
- CLEANUP: separate error handling into separate files.
- FIXED: RATIONAL_TREESshould now work in all built-ins.
- FIXED: make sure the GC does not follow invalid trail entries.
Yap4.1.6:
	- NEW: execute_goal(Goal)function allows calling Prolog from C. Still under testing, and not yet officially in the interface. Note that execute_goal will destroy all X arguments, and that it only keeps the first solution (it performs an implicit cut).
- FIXED: complaints while compiling YAP in WIN/NT platform.
- FIXED: debugger got confused when quasi-skipping through inline builtins.
- FIXED: DEPTH_BOUND_CALLwas not restoring depth forretry_c.
- NEW: compilation flag LOW_LEVEL_TRACER, if this flag is defined, enables detailing execution. Use start_low_level_trace and stop_level_trace, or T from interrupt to access this functionality.
- CLEANUP: overflows are now processed within the emulator, not back in the caller.
- FIXED: memory allocation during boot could crash returning NULLpointer, system would then crash.
- ISO-YAP: many new predicates, major rewrite of manual.
- FIXED: debugger should now understand better immediate update semantics (eg, dynamic predicates).
- ISO-YAP: all error handling is now ISO style.
- FIXED: could not write MIN_INT.
- ISO-YAP: add Z is float_integer_part(X).
- ISO-YAP: add Z is float_fractional_part(X).
- ISO-YAP: arg/3now generates errors.
- ISO-YAP: abolish/1 now does errors the YAP way, and only abolishes dynamic procedures. Use abolish/2to clear static procedures.
- Break boot.yapfile into smaller files.
- YAP now compiles well under Linux/Alpha.
- X now is called XREGSto avoid problems with Linux/Alpha includes.
- Abort now jumps to before the absmi emulator and then does a long cut. This should simplify YapOr, and allow for restricting toplevels.
Yap4.1.5:
	- FIXED: MAX_INTonTags_LowTagwas wrong.
- NEW: first cut of profiling. Right now, Currently, for static predicates, profiling disables indexing. That should be fixed in the next version.
- NEW: source mode debugging is active. Compile with ":- source" and debug/step through all your builtins!
- FIXED: major bug in cut_by, since early 4.1 :-(. Affects debugging.
- NEW: fetch first op from pred before jumping.
- NEW: use SREGto cacheA1for switches and tries.
- FIXED: warning messages for SGI CC.
- FIXED: warning messages for alphas.
- NEW: optimise switch_on_listfor the list case.
- NEW: WAM registers optimised for MIPS.
- FIXED: shadow CPandHBon sparcs. They need every bit of performance we can get them.
- FIXED: famous curprio bug in parser, from now on parser backtracks cleanly.
- NEW: Got rid of SREGfor call-type instructions.
- NEW: CPREGinabsmifor Suns.
- CLEANUP: got rid of obsolete absmi regs.
- FIXED: small bug in the Prolog code for unknown/2.
- NEW: Small speed improvements for complex absmi instructions.
Yap4.1.4:
	- NEW: read_term/3and new syntax_error option toyap_flag.
- FIXED: got rid of fast predicates from compiler.
- NEW: Makefile now generates a bootable save state as YAP default.
- NEW: started working on manual for 4.1. Fixed info format so that it will generate info files. Add several missing built-ins to manual.
- NEW: bootable saved states with arguments, accessible though unix(argv(L)).
- NEW: optimised code for tests (var/1and friends) and arithmetic (is/2).
- NEW: much faster code for /\,\/,>>and<<.
- FIXED: debugger does not go into recorded/3and friends.
Yap4.1.3:
	- NEW: unix(argv(X)).
- FIXED: abscomplains ifint != Int.
Yap4.1.2:
	- NEW: saved states now search for $BINDIR/yap.exeto boot.
- FIXED: bugs with handling errors.
- FIXED: got rid of $recorded/3for now.
- NEW:  generate specialised code for OR,AND, SHIFT LEFT, andSHIFT RIGHT.
- FIXED: statistics(runtime,_)now does not count GC time, as in other Prologs.statistics(cputime,_)counts everything.
- FIXED: time is returned as an integer, not as a float.
Yap4.1.1:
	- CLEANUP: get rid of warnings under Cygnus GCC.
- FIXED: Use Windows memory allocation routine, now YAP can recover from saved states for smaller stacks.
- CLEANUP: don't use the UNIX define. Use insteadconfigureto say exactly which UNIX feature you need.
- FIXED: compiler would not handle correctly unsafe variable from disjunctions.
- FIXED: force indexing to ask for more stack if stack runs out. This should help if you have really many clauses.
- CLEANUP: clean all error code from C to use the new Error()routine.
- NEW: use throw/1to send system errors.
- NEW: catch/3andthrow/1.
- NEW: load_foreign_file/3for SunOS4 (tested) and AIX (compiles).
Yap4.1.0:
	- NEW: memory mapped arrays.
- NEW: make garbage collector expand stack quickly to avoid excessive number of GCs.
- NEW: do the same for heap overflow detector.
- CLEANUP: cleanup readline code for not using strcpy,strlenand friends. Current code was broken for very large input strings.
- NEW: sortand friends implemented in C.
- NEW: Removed 256B limitation on atom size while parsing.
- CLEANUP: Change AllocCodeSpaceto returnNULLon code failure, makecclause()call growstack on stack failure.
- NEW: Static Arrays!
- Split previous support for arrays and co-routines. We now have TERM_EXTENSIONSto control extensions to unification. Tried to redesign the extensions so that they would be modular, the fileTermExt.h.m4shows how to implement an extension.
- Got rid of lock_predand friends. Usage of static predicates is now detected when compilation starts, or when assert is used.
- Got rid of hash table in optimise_ce, it wasn't working.
- Current predicate access:
	
		- add new argument to call, so that call can recognise which predicate it is working on.
- add extra argument to tryand frieds, so that they can directly access a predicate.
 
- Internal cleanup: change cdmgr.cand friends so that we now move in a clause through the Clause structure. Get rid of ptrs, except forsave.c.
- Changes to immediate update semantics implementation:
	
		- Entries are now removed from the chain immediately, instead of only when they are physically deleted.
- Each entry has an age (positive if entry is from recordz, negative if fromrecorda).
- When we backtrack to deleted entries, we search the property list for entries with younger ages.
- When we erase a clause, we don't place a fail in the clause. Instead, we remove the clause from the chain immediately.
 
- NEW: MIPS architecture support in Regs.handabsmi.c.
- X86 Speedups:
	
		- Force opcode prefetching for simple instructions in X86.
- Cache Yfor control instructions in X86.
- Optimise Bind()for X86 by jumping only if we need to trail for cases close to the end of the instruction. This does not seem to improve performance for X86 machines.
- Cache SREGusage.
 
- Cleanup:
	
		- Move AuxSpandAuxToptoREGS.
- Use Auxfor emulatorPDL.
 
- Cleanup: compiler.h. Use enum for compiler ops.
- NEW: Indexing:
	
		- simplify GCandORP: instructions do not store intermediate values in global.
- unnecessary instructions purged.
- new try_tailliketrail_head, but jumps to atomic code.
- switch on types insts after backtracking now look like retry and have correct clause information for ORP.
- switch_on_typetalks to- switch_on_functhrough- S, and to switch on cons through- A[0].- I_Rdisappeared.