infinite abort() in a backrace of a c++ program core dump

Question

I have a strange problem that I can\'t solve. Please help!

The program is a multithreaded c++ application that runs on ARM Linux machine. Recently I began testing it for

Answer 1

One possibility here is that something in that thread has very, very badly smashed the stack by vastly overwriting an on-stack data structure, destroying all the needed data on the stack in the process. That makes postmortem debugging very unpleasant.

If you can reproduce the problem at will, the right thing to do is to run the thread under gdb and watch what is going on precisely at the moment when the the stack gets nuked. This may, in turn, require some sort of careful search to determine where exactly the error is happening.

If you cannot reproduce the problem at will, the best I can suggest is very carefully looking for clues in the thread local storage for that thread to see if it hints at where the thread was executing before death hit.

Answer 2

My guess for the "infinite' aborts is that either abort() causes a loop (e.g. abort -> signal handler -> abort -> ...) or that gdb can't correctly interpret the frames on the stack.

In either case I would suggest manually checking out the stack of the problematic thread. If abort causes a loop, you should see a pattern or at least the return address of abort repeating every so often. Perhaps you can then more easily find the root of the problem by manually skipping large parts of the (repeating) stack.

Otherwise, you should find that there is no repeating pattern and hopefully the return address of the failing function somewhere on the stack. In the worst case such addresses are overwritten due to a buffer overflow or such, but perhaps then you can still get lucky and recognise what it is overwritten with.