On Sun, 10 Feb 2008, Pritpal Bedi wrote: > Hello Everybody > I receive this error when executing modules with parent/child relations. > Child records are shown in a TBrowse. > DO_MENU (149) description Object Destructor Failure > MAIN (150) genCode 45 > operation Reference to freed block > I have tried to investigate where is the problem, but am not been able to > figureout the exact sequence exactly in what circumstances does it happen. > Even a simple Next/Prev movement produces this error. Anybody have a clue as > to what circumstances may be leading to this error. xHarbour and Clipper > compilations just do fine.
Clipper does not have destructors and xHarbour cannot detect most of destructors errors at all what causes memory corruption and later GPFs. See tests/destruct.prg as an example of such errors. It also illustrates why destructors are not safe in xHarbour which cannot cleanly serve .prg code errors. > Error handler control this error and then applicatiion GPF's. I will be > trying more to isolate the problem. For sure somewhere deep inside GC > something is happening weired. The offending line is: It's reported from GC but the problem is in your code and it's caused by some destructor you are using (like in destruct.prg) or by C code which keeps references to collectible block in unknown for GC place. 1-st I would look for all destructors in your whole code and try to isolate the problem. It does not have to be related to BROWSE object at all. Of course it's also possible that it's a bug in core code so if you can isolate it to small example then please inform me. In isolating process hb_gcAll(.t.) can greatly help - it will force error message because your object has cross references and it's freed only by GC. best regards, Przemek _______________________________________________ Harbour mailing list Harbour@harbour-project.org http://lists.harbour-project.org/mailman/listinfo/harbour
