July 2005 - PPL-devel - BUGSENG Mailman

Re: Problems with XSB 2.7.1
by Roberto Bagnara 06 Jul '05

06 Jul '05

Terrance Swift wrote: > First, thank you Roberto for your help and patience in finding a bug. > I was away from email this morning, which I guess was fortunate for me > in that you and David did the work in isolating problematic behavior. > > There are actually two issues. The first is that if you call > flush_output/1 with an atom that is not an alias it fails silently, > rather than raising an exception. This is a bug. > > The second is the use of user_output as an alias for the current > output stream. I had been under the impression that the ISO standard > used user_out rather than user_output, but I should recheck my copy (I > dont have it with me for the weekend, and it doesn't seem to be > available on line). However, since other Prolog's support user_output > (at least Sicstus does) I should also include user_output and > user_input as aliases. They are indeed specified by the ISO standard: 7.10.2.2 and 7.10.2.3, page 55. > I'll make the fixes in sourceforge this afternoon. It may require > changes to a couple of files. > > As a workaround, you can 1) check out XSB from sourceforge under > anonymous CVS (after I make the changes) or 2) use one of these in > your code > > | ?- flush_output(userout). > | ?- flush_output(user_out). > | ?- flush_output. > > or 3) undefine flush_output/1 as a standard predicate in your copy of > XSB (easy, and I can tell you how to do this if this is what > you want to do). I think (3) is the best option for me. In fact, the users involved are unlikely to want to use a non-official release, which rules out (1), while (2) would require me to change the system-independent part of my code. So, if you teach me how to implement (3), I have the temporary workaround I was looking for. Many thanks, Roberto > Terry Swift > > > > > On Fri, 1 Jul 2005, Roberto Bagnara wrote: > > >>David Warren wrote: >> >>>You've enabled more debugging than I ever have... It gets through the >>>compilation of the emulator, but then fails as it begins to recompile >>>the prolog compiler. It seems to have completed compilation of the >>>first file, so you've gotten reasonably far into the XSB code. THis >>>means it is most likely not the tagging scheme, with which we formerly >>>had problems under fedora. >>> >>>It looks like here it may have something to do with file i/o? What if >>>you try to execute other simple files with this emulator? I.e., just >>>try to use this emulator to execute something simple. >>> >>>Going back to the original system, did you configure it (before trying >>>to enable debugging)? Did it get through the recompilation of the >>>prolog compiler and system directories? If so, then this seems to be >>>a problem with the debug configuration. If we go back to the original >>>problem of a loop in some code that ought to run, where was that loop? >>> Could we trace or instrument that original program to try to see >>>where the loop was? Or was it so early, you couldn't find it in the >>>Prolog code? >>> >>>So, to summarize. It might be the debugging code that is causing the >>>problem here, and it may be easier (or may not) to go back to the >>>original nondebugging version to try to see what's going on there. If >>>it getting into Prolog code, it might be easier to try to track down >>>the loop using Prolog tracing or other Prolog techniques. >> >>Dear David, >> >>you are right: the one I reported is probably a bug concerning >>the debugging options. The problem was that my code makes heavy >>use of the foreign language interface and with the optimized version >>I was unable to understand where the problem occurred. >> >>Now I have configured XSB with >> >> ./configure --prefix=/usr/local/lib/xsb --enable-debug --disable-optimization >> >>and this gave me the possibility to ascertain that my problem was >>in the Prolog part. Everything boils down to the fact that the >>query >> >> ?- flush_output(user_output). >> >>silently fails. This is strange, because flush_output/1 >>is an ISO builtin, user_output is, in ISO Prolog, an alias >>for the user output stream. >> >>Passing from XSB 2.6 to 2.7.1 I was brought to remove my >>definition >> >>:- import file_flush/2 from file_io. >> >>flush_output(user_output) :- >> file_flush(0, _). >> >>because of the error >> >>++Error[XSB]: [Compiler] Trying to redefine the standard predicate: flush_output/1 >>The file ./xsb_clpq.xwam is removed >>Aborting... >> >>I thought: "cool, they have incorporated more ISO features!" >>What am I doing wrong? >>Many thanks, >> >> Roberto >> >>-- >>Prof. Roberto Bagnara >>Computer Science Group >>Department of Mathematics, University of Parma, Italy >>http://www.cs.unipr.it/~bagnara/ >>mailto:bagnara@cs.unipr.it >> >> >>------------------------------------------------------- >>SF.Net email is sponsored by: Discover Easy Linux Migration Strategies >>from IBM. Find simple to follow Roadmaps, straightforward articles, >>informative Webcasts and more! Get everything you need to get up to >>speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click >>_______________________________________________ >>Xsb-development mailing list >>Xsb-development(a)lists.sourceforge.net >>https://lists.sourceforge.net/lists/listinfo/xsb-development -- Prof. Roberto Bagnara Computer Science Group Department of Mathematics, University of Parma, Italy http://www.cs.unipr.it/~bagnara/ mailto:bagnara@cs.unipr.it

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w3ppl/htdocs/Credits Credits.raw
by Roberto Bagnara 06 Jul '05

06 Jul '05

CVSROOT: /cvs/ppl Module name: w3ppl Changes by: roberto(a)cs.unipr.it 2005-07-06 11:34:54 Modified files: htdocs/Credits : Credits.raw Log message: Thank Francesco Logozzo for the positive interaction that allowed us to improve portability on Cygwin. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/w3ppl/htdocs/Credits/Credits.raw.…

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ppl STANDARDS
by Enea Zaffanella 06 Jul '05

06 Jul '05

CVSROOT: /cvs/ppl Module name: ppl Changes by: zaffanella(a)cs.unipr.it 2005-07-06 10:58:13 Modified files: . : STANDARDS Log message: Minor typo correction. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/STANDARDS.diff?cvsroot=ppl&r1…

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ppl src/Powerset.defs.hh ./TODO
by Enea Zaffanella 06 Jul '05

06 Jul '05

CVSROOT: /cvs/ppl Module name: ppl Changes by: zaffanella(a)cs.unipr.it 2005-07-06 10:57:58 Modified files: src : Powerset.defs.hh . : TODO Log message: One item in the huge list has gone. Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/Powerset.defs.hh.diff?cvs… http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/TODO.diff?cvsroot=ppl&r1=1.14…

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ppl ./Makefile.am ./NEWS ./README ./TODO ./con ...
by Roberto Bagnara 06 Jul '05

06 Jul '05

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Restoring dimensions
by Mario Mendez 05 Jul '05

05 Jul '05

Hi all, I'm working with your PPL library by using the Prolog interface, although my question is generic. Say we have a 3D polyhedron P defined by (for example): [A > 0, A + B < 3, C=4] Now we project *ppl_Polyhedron_remove_space_dimensions* over {A,C} getting P': [ 3>A>0, C=4 ]. Later on we want to intersect the projected eq.system P'(that might be altered during the program) with P. The problem is that our 'C' is VAR(2) in P but VAR(1) in P' so a call to *ppl_Polyhedron_add_constraints_and_minimize* adding to P the Constraint System of P' produces an undesired output-> ... A = '$VAR'(0),B = '$VAR'(1), C = '$VAR'(2), ppl_new_Polyhedron_from_constraints(nnc,[A>0,A+B<3,C=2],Poly1), ppl_new_Polyhedron_from_Polyhedron(nnc,Poly1,nnc,Poly2), ppl_Polyhedron_remove_space_dimensions(Poly2,[B]), ppl_Polyhedron_get_minimized_constraints(Poly2,Poly2_Cons), ppl_Polyhedron_add_constraints_and_minimize(Poly1,Poly2_Cons),!, ... no , although the original system is solvable How can we add dimensions to P' so the intersection with P saves the original information about B? Note that B is not the first dimension (so we cannot use *concatenate_assign* nor the last one (so we cannot use *add_space_dimension*. An "ad-hoc" solution might store the deleted indexes and then make a version of the Constraint System of P' with all the VAR(X) renumbered according to that information, so a call to *add_constraints* makes sense, but I wonder if there's an alternative just using the API. Thanks! PS: Assume that the projection is mandatory Mario

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w3ppl/htdocs/Bugs Bugs.raw archive.raw
by Enea Zaffanella 04 Jul '05

04 Jul '05

CVSROOT: /cvs/ppl Module name: w3ppl Changes by: zaffanella(a)cs.unipr.it 2005-07-04 15:58:32 Modified files: htdocs/Bugs : Bugs.raw archive.raw Log message: Documented bug in Polyhedron::genrealized_affine_image(). Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/w3ppl/htdocs/Bugs/Bugs.raw.diff?c… http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/w3ppl/htdocs/Bugs/archive.raw.dif…

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ppl/src Polyhedron_public.cc
by Enea Zaffanella 04 Jul '05

04 Jul '05

CVSROOT: /cvs/ppl Module name: ppl Changes by: zaffanella(a)cs.unipr.it 2005-07-04 15:57:43 Modified files: src : Polyhedron_public.cc Log message: Corrected symmetric bug on the other flavor of method Polyhedron::generalized_affine_inage(). Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/src/Polyhedron_public.cc.diff…

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ppl/tests/Polyhedron Makefile.am generalizedaf ...
by Enea Zaffanella 04 Jul '05

04 Jul '05

CVSROOT: /cvs/ppl Module name: ppl Changes by: zaffanella(a)cs.unipr.it 2005-07-04 15:56:59 Modified files: tests/Polyhedron: Makefile.am Added files: tests/Polyhedron: generalizedaffineimage14.cc Log message: New test show symmetric bug on the other flavor of generalized_affine_image(). Patches: http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/tests/Polyhedron/generalizeda… http://www.cs.unipr.it/cgi-bin/cvsweb.cgi/ppl/tests/Polyhedron/Makefile.am.…

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Re: PPL instalation and .so libraries
by Roberto Bagnara 04 Jul '05

04 Jul '05

Jose Morales wrote: > Hi Roberto, > > some PhD students at Madrid & New Mexico have been trying to install > PPL 0.7 to be used with Ciao and had some problems. 'libppl_ciao.so' > was not found during module loading. We thought it could be Ciao's > fault until we tried the Yap interface and same problem showed up. > Later we realized that the PPL .so libraries were installed in > /usr/local/lib/ppl, and although we run ldconfig we had completely > forgotten to modify /etc/ld.so.conf. > > Have you considered installing libppl_* directly in /usr/local/lib so > that no change in /etc/ld.so.conf is required? If this is a problem, > making a link should also do the trick. Or, if the message which > appears during compilation/installation were more prominent, that > would also help. Are we the only ones bitten by this? It seems like > a candidate for a Frequently Asked Question, or a bullet in some quick > installation instructions. > > Thanks in advance for the help. Dear Jose, the intention here is not to keep the PPL somewhat confined and not to clutter $prefix/lib (where $prefix could well be /usr and not /usr/local). This may seem an excessive worry right now, but future releases of the PPL may have dozens of .so libraries for several foreign language interfaces (not only the various Prolog systems). We will definitely add a note in the FAQs. Many thanks, Roberto -- Prof. Roberto Bagnara Computer Science Group Department of Mathematics, University of Parma, Italy http://www.cs.unipr.it/~bagnara/ mailto:bagnara@cs.unipr.it

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