On Thu, 6 Jun 2013, Matteo Semplice wrote: > On 05/06/2013 16:56, Roy Stogner wrote: >> >> If you're seeing a segfault, the first thing you should do is switch >> from opt to debug mode. Then typically you'll fail an informative >> assertion before you ever get to the segfault point, and even in the >> worst case at least you can start things up in a debugger and have >> more context to step through. >> > Hi, I am afraid I don't seem to hit any assertion failure... The > backtrace at the bottom of my email was obtained with the program > compiled in debug mode.
This bit stands out! > /home/matteo/libmesh-0.7.2/libmesh/include/mesh/vtk_io.h, line 153, libMesh 0.7.2 is a year and a half (and about 3 releases) old, and although I don't recall any bugfixes since then affecting FEMSystem quadrature, I wouldn't swear to that. And if there are any *unfixed* bugs affecting FEMSystem quadrature, it'll be easier for others to help you if you're using 0.9.1 or the git trunk. I'll pull down a 0.7.2 copy and see if I can see anything obvious there, though. Strange. On line 575 it's not actually a quadrature access that's segfaulting; it looks like it's an invalid pointer to one of the FE objects. You didn't clear or swap or anything to those, did you? > Anyway, here it is again. But perhaps I should change my question to > "what is the proper way to change the quadrature rule in a > FEMSystem?" Three steps: Delete the current element_qrule (and/or side_qrule) Set it (or them) to the address of new-allocated QBase(s) of your choice. Loop over element_fe (and/or side_fe) and attach_quadrature_rule() to each. I don't know if this has been tested, though. --- Roy ------------------------------------------------------------------------------ How ServiceNow helps IT people transform IT departments: 1. A cloud service to automate IT design, transition and operations 2. Dashboards that offer high-level views of enterprise services 3. A single system of record for all IT processes http://p.sf.net/sfu/servicenow-d2d-j _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
