Oh, zut! (responding to myself) > (there are several use of 'CATCH' and there is 'handler-bind').
Badly handled. CTRL-C for example. More work needed in this regard. Le mer. 22 mai 2024 à 22:03, Grégory Vanuxem <g.vanu...@gmail.com> a écrit : > > Hello Waldek, hello all, > > First, thanks for your response, it was very instructive it leads me > to solve this long outstanding issue with my FriCAS copy. > > Le mar. 21 mai 2024 à 20:32, Waldek Hebisch <de...@fricas.org> a écrit : > > > > On Tue, May 21, 2024 at 01:57:45PM +0200, Grégory Vanuxem wrote: > > > Hello, > > > > > > I try to understand why a Clozure CL 'terminate' method is not called > > > from the interpreter. I have a CL class jlref, when a jlref object is > > > no longer referenced the CL garbage collector reclaims it. It is > > > possible in different CL implementations to add a 'hook' to do some > > > job at that time. Personally I then unreference the real Julia object > > > in such a way it can be GC reclaimed in Julia, jlref is just a class > > > that holds information about it. > > > > > > For SBCL I have no problem, but 'ccl:terminate' which should be > > > automatically called is never called. But, and this is the main point, > > > following an advice in a Clozure mailing list, I tried to use/define > > > this method directly at execution time using ')fin', and surprisingly, > > > using ')fin' automatically triggers 'terminate' on every objects that > > > are/(were ?) reclaimed. > > > > > > So my question, what does ')fin' do? And do you happen to know where I > > > need to look in the FriCAS source code to better understand its > > > effect? > > > > AFAIK ')fin' is doing "nothing", is just returns back to whatever Lisp > > was doing befor calling FriCAS. To understand relation with Lisp, > > look at 'src/lisp/fricas-lisp.lisp', in particular 'save-core-restart'. > > Yes!!! This is what helped me. I looked more carefully at this function and.. > > > > > > Furthermore, in src/interp/int-top.boot, the documentation says that > > > to return to the interpreterafer after ')fin' '(restart)' should be > > > used. In fact, before some change in the FriCAS source I think, so I > > > used (|spad|). Again following an advice. And, again, with Clozure CL, > > > contrary to SBCL, that leads to strange things after returning to the > > > interpreter and executing foreign code (principally bad addresses and > > > therefore segfault). > > > > The function to start FriCAS is 'fricas_restart'. 'fricas_restart' > > is doing some initialization which may be unnecessary when executed > > second time. OTOH re-doing initalization should be harmless and > > some probably is needed. > > I see that, and in fact only propog CL use (|spad|) directly in other > piece(s ?) of code. Using it is handy though, not everything is > reinitialized. > > > Note that ')fin' is really unsuppored by FriCAS, basically > > it is "pray that Lisp will do what you want". In particular IIRC > > it simply quits FriCAS when using ECL and I think it never fully > > worked with Clozure CL. > > > > > So maybe I first need to know a better CL command, to return to the > > > interpreter? But also, of course, to know why the ccl:terminate is not > > > called in the interpreter. R. Munyer in the CCL mailing list found a > > > way, see the attached transcript file, but he uses ')fin' and no > > > Clozure CL FFI. I tried to use different (eva-when) to define the > > > ccl:terminate method without success since the code is build/compiled > > > (src/lisp). > > > > I think that ')fin' is irrelevant, you should get the same effect > > using ')lisp' or if that is inconvenient you can put code in the > > file and use ')read'. The main difference is that FriCAS needs > > specific settings of several global variables and FriCAS catches > > errors (there are several use of 'CATCH' and there is 'handler-bind'). > > This _should_ make no difference. What _may_ matter is order of > > initialization. In particular FriCAS performs some initializations > > before dumping image. But several thing do not survive to > > restarted image, so need to be done later, after start of new image. > > I guessed after your email that the behavior of ')fin' is somewhat undefined. > > So now, my solution to my problem. A proposed diff is attached, it > uniformizes/simplifies the Clozure CL boot I think. > > Looking at the attached transcript in my previous email I was > surprised to see that the banner was displayed at that time, and > experimenting more with the pure CL interpreter after ')fin' I first > saw that calling Julia was not possible. When you embed Julia using > libjulia, Julia does not support multithreaded code from the host > process, I encountered this with SBCL, and it leads to segfault, bad > stack etc. Only the thread that initialized Julia is able to use > commands using the C interface. Experimenting some interruptions and > backtraces I saw a thread started after ')fin'. Apparently the "main" > process (not exactly in fact, the actual boot process of FriCAS bypass > the CCL read-eval-print loop main thread) was at that time in a idle > state or not started or sleeping, I don't really know, and the > ccl::terminate method is then called on reclaimed CL objects. It's > another thread in fact. FriCAS on CCL is then a multithreaded app :-) > > Diggering more in 'save-core-restart' I saw that only FriCAS on top of > CCL is using a fricas-application class, which is just a > ccl::application class: > > (defclass fricas-application (ccl::application) ()) > > and uses it for the ccl::toplevel-function at startup. My main problem > is that with this class 'ccl::terminate' is not executed and the > "main" process/thread is needed to execute it. To speak frankly I do > not really understand why, SBCL, for example, can populate a threaded > compatible FIFO queue in a garbage collector thread. > > I so cleaned/uniformized the FriCAS on CCL startup not to use this > class which apparently runs in another thread than the "main" thread. > Uniformized in the sense that the other CL implementations do not need > a particular class for FriCAS. The modification is very simple (also > attached): > > ======================================================= > diff --git a/src/lisp/fricas-lisp.lisp b/src/lisp/fricas-lisp.lisp > index bf46a61..4e7a222 100644 > --- a/src/lisp/fricas-lisp.lisp > +++ b/src/lisp/fricas-lisp.lisp > @@ -64,24 +64,10 @@ with this hack and will try to convince the GCL > crowd to fix this. > ;; > #+:openmcl > (progn > - > -(defclass fricas-application (ccl::application) ()) > - > -(defvar *my-toplevel-function* nil) > - > (defvar *ccl-default-directory* nil) > - > -(defmethod ccl::toplevel-function ((app fricas-application) init-file) > - (declare (ignore init-file)) > - (call-next-method) ; this is critical, but shouldn't be. > - (funcall *my-toplevel-function*) > - (let ((ap (make-instance 'ccl::lisp-development-system))) > - (ccl::toplevel-function ap init-file))) > - > ;;; Disable default argument processing > (defmethod ccl::process-application-arguments > - ((app fricas-application) error-flag opts args) nil) > - > + ((app ccl::application) error-flag opts args) nil) > ) > > ;;; Disable argument processing in GCL > @@ -143,12 +129,11 @@ with this hack and will try to convince the GCL > crowd to fix this. > #'(lambda () nil))) > (top-fun #'(lambda () > (set-initial-parameters) > - (funcall restart-fun)))) > + (funcall restart-fun) > + (ccl::toplevel-loop)))) > (setf *ccl-default-directory* ccl-dir) > - (setf *my-toplevel-function* top-fun) > - (CCL::save-application core-image > - :PREPEND-KERNEL t > - :application-class > 'fricas-application) > + (CCL::save-application core-image :toplevel-function top-fun > + :PREPEND-KERNEL t) > (QUIT)) > #+:lispworks > (progn > ======================================================= > > And as you can see with '(ccl::toplevel-loop)' in 'top-fun', this > allows the user to enter in the Clozure CL REPL with ')fin' in a > relatively clean manner. I tested this code with SBCL and Clozure CL, > tests passed. That also solves my issues and, how I view this, this is > cleaner. > > Thoughts? > > - Greg -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop receiving emails from it, send an email to fricas-devel+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/fricas-devel/CAHnU2dZXXO0ymO33X6yv2wNQir66GA_%3Dp_r0LntghizeM3tPHQ%40mail.gmail.com.
