Re: Recursion crash in STL on linux
boltar2003@boltar.world wrote:
I don't know if this is a gcc C++ implementation issue (I suspect it
is) or a linux issue so I'm hedging my bets by posting to 2
newsgroups.
I have a C++ program for linux that does a LOT of recursion due to
searching etc which I won't bore you with but I am getting consistent
crashes in the STL. This appears to be due to running out of stack or
heap space but all that happens is the container crashes , there is no
exception thrown and no way of knowing when its going to happen. Sure
I can limit recursion depth but it would be nice to know when the
stack limit is about to be hit.
So does anyone know a way in linux of checking the amount of stack
space or heap space left for a process (hopefully not something kludgy
like attempting to just malloc a large amount of memory to see what
happens) or
is there a way to get around this apparent bug in the STL and make it
chuck an exception if this sort of thing happens?
This is not a bug in the STL.
Guarding against memory corruption requires a lot of overhead and even
then it isn't guaranteed to be successful. C++ errs on the side of
running lean so if you want such guards, you have to implement them
yourself (or find a tool that does it for you.)
What I would do in your shoes is (1) try to isolate the recursive
algorithm and prove that it works with test cases. (2) use the test
cases to convert the recursive algorithm to an iterative algorithm. (3)
put the iterative algorithm into the main program and see if the bug
still happens.
If the bug is gone, then you can be reasonably sure that it was due to
overflowing the stack and continue with the project. If the bug is still
there (it will have moved, but it will still be a SIGSEGV,) then you can
be reasonably sure that there is undefined behavior somewhere in your
program (most likely dereferencing an uninitialized pointer, or a
pointer that is pointing to a deleted object.)
Good luck.