libmetis__CheckBnd2 message, cause?

I am using the ParMETIS_V3_PartKway API to partition graphs. In some circumstances I get the assertion failure message:

***ASSERTION failed on line 185 of file debug.c: nbnd == graph->nbnd
15 16

It seems that I still get a valid partition out of ParMETIS, but I would like to correct this problem. Unfortunately, I don't have any idea about what could be wrong with the input that I am giving ParMETIS that could be causing the problem. This code has worked for many years with the 3.1 version but I recently upgraded to version 4.0 and started getting these messages on occasion. Any idea what could be causing this?

Thanks,
-Ed

RE: It seems that this is a bug

It seems that this is a bug in the boundary code calculation that kicks in when the graph that you are partitioning is not connected. It does not affect the correctness of the solution, just the sanity checking code.

BTW, why was NDEBUG turned on? Did you manually edit those settings?

George

RE: Fix found, and question

OK, I discovered that in the process of compiling the code I did not have the -DNDEBUG and -DNDEBUG2 options set. It seems that these are usually set in the default configuration.

Question: is there anything to worry about that these debugging assertions are being tripped sometimes? Turning on the NDEBUG flags got rid of the messages, but it leaves me with a worry that something might not be quite right.

Thanks,
- Ed