CGAL users discussion list

[Mike V <>]

Hello,

The issue I mentioned in my previous email has been resolved after discussion 
with Guillaume Damiand. I am facing a broader issue with my code. I am using 
CGAL to perform mechanical simulations, and I am finding irreproducible 
results (significantly different positions, not just the ordering of the 
vertices), even with fixed compilation flags and random number generation. 
This suggests that I am reading from invalid or uninitialized memory.

I was able to reduce the error (push back the disagreement to a later time 
step) by finding a place where I used a Iterator to index into a map whose 
keys were Handles. I suspect that I am doing this elsewhere, but it is hard 
to find it. This earlier mistake gave no errors when compiling (with regards 
to type mismatch), and running the code through Valgrind and Dr. Memory 
states that there are no leaks/ invalid reads and writes (I had to disable 
rounding checks to get these to work). Oddly enough, when I look at the 
output of running my code through Valgrind, the results are consistent across 
different compilation methods and different from executing the debug and 
release builds without Valgrind.

I can go through my code, searching for all instances where I use a map or 
try to read memory and place a bunch of assertions there, but this is time 
consuming, and it would be nice if there was a systematic tool I could use to 
help find these errors. Does anyone have experience using tools to debug 
these kinds of issues in CGAL code? Is there software/ options you could 
recommend?

I appreciate any advice on this.

Thank you,

Mike