Thank you for your bug report. > I was using the Graph method with the algorithm Relax-IV from GLPK 4.60 > with successful results. > But now, when I migrate to GLPK 4.63, the same code is causing a error: > > > glp_free: memory allocation error > Error detected in file ..\svr\env\alloc.c at line 72 > > > This occur when I call one of both functions: > > > glp_delete_v_index > glp_delete_graph > >
There were no changes between 4.60 and 4.63 regarding these functions, so this looks like a latent bug which was not observed before. Please note that there is a bug in the original RELAX IV Fortran code, which I tried to fix with a brute force changes; see https://lists.gnu.org/archive/html/bug-glpk/2013-04/msg00009.html (I reported this bug to Prof. Bertsekas, the author of RELAX IV, however, he was not able to help me, because the code was written a long time ago, and he just didn't remember details.) Also it may happen that the bug in your code, so please check it more carefully. The message "glp_free: memory allocation error" means that the header of some dynamically allocated block was clobbered by using an invalid pointer to store data. > > I hope I can help with the improvement of the tool. > If you wish to help, please try to replace a call to glp_mincost_relax4 by a call to glp_mincost_okalg that solves the same problem. If the bug will disappear, it is most likely in RELAX IV code. If not, it is most likely in your code. You also may try to use valgrind to obtain a more detailed information about the bug. In any case, please report your results. Thanks. Andrew Makhorin _______________________________________________ Bug-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/bug-glpk
