Is there a good way to destroy caller's stack in C++?

Question

There are some tricks practicing C++ programmers do know like "Scope Guard" and maybe others involving references to temporaries.

I'm not a practicing C++ programmer, but I'd like to ask (of curiosity) if there is a way third party library could harm the callers' stack somehow. Maybe involving sudden destructors or some kind of other scoped lifetime magic?

Answer 1

way third party library could harm the callers' stack

Whenever code from the third part library runs - whether an initialisation routine for a dynamically loaded library that the OS loader knows to call, or an explicit call from the client application code - it usually (in most OSes'/implementations' security model) has as much ability to screw with the stack (or any other memory) as the client application itself; for example:

void library_code()
{
    char x;
    char* p = &x;
    *(p - 2) = 23;  // undefined behaviour - may do nothing or anything,
                    // but usually overwrites stack or SIGSEGVs
    *(p + 54) = 99; // stacks might grow up or down, so may have to + or -
                    // from &x to address in-use stack memory...
}