Catching “Stack Overflow” exceptions in recursive C++ functions

Question

Is it possible to catch a stack overflow exception in a recursive C++ function? If so, how?

so what will happen in this case

void doWork         


        

Answer 1

On what OS? Just for example, you can do it on Windows using Structured Exception Handling (or Vectored Exception Handling). Normally you can't do it with native C++ exception handling though, if that's what you're after.

Edit: Microsoft C++ can turn a structured exception into a C++ exception. That was enabled by default in VC++ 6. It doesn't happen by default with newer compilers, but I'm pretty sure with a bit of spelunking, you could turn it back on.

It's true that when this happens, you're out of stack space. That's part of why I mentioned vectored exception handling. Each thread gets its own stack, and a vectored exception handler can run in a separate thread from where the exception was thrown. Even SEH, however, you can handle a stack overflow exception -- it just has to manually spawn a thread to do most of the work.

Answer 2

Of course, you could avoid the recursion problem by converting it to a loop.

Not sure if you're aware of this but any recursive solution can be translated to a loop-based solution, and vice-versa. It is usually desirable to use a loop based solution because it is easier to read and understand.

Regardless of use of recursion or loop, you need to make sure the exit-condition is well defined and will always be hit.

Answer 3

In Windows you can use structured exception handling (SEH), with __try and __except keywords to install your own exception handler routine that can catch stack overflows, access violation, etc etc.

It's pretty neat to avoid Windows' default crash dialog, and replace it with your own, if you need to.

Answer 4

There's really no portable way to do it. An out of control recursive function will usually cause an invalid memory access when it tries to allocate a stack frame beyond the stack address space. This will usually just crash your program with a Segmentation Fault/Access Violation depending on the OS. In other words, it won't throw a c++ exception that can be handled in a standard way by the language.

Answer 5

You have to know always a level of your recursion and check it if greater than some threshold. Max level (threshold) is calclulated by ratio of stack size divided by the memory required one recursive call.

The memory required one recursive call is the memory for all arguments of the function plus the memory for all local variables plus the memory for return address + some bytes (about 4-8).