Ok, this is an option and I hate it, but I am open if to notes if anyone has any. I think I might have to inline assembly. Here is my first attempt:

static
void rmFillStackData(size_t bytes, unsigned char value)
{
   if(bytes > 0)
   {
      // If anyone knows a better way to do this, please let me know
#if defined(__x86_64__) || defined(_M_X64) || defined(i386) || defined(__i386__) || defined(__i386) || defined(_M_IX86)
      // This works by assuming that the last parameter "value" is at the bottom
      // of the stack. So writing below it is fine. This also assumes the 
      // address of the stack pointer get smaller as the stack gets fuller.
      asm volatile ("loop:\n\t"
                    "mov %1,(%2)\n\t"
                    "dec %2\n\t"
                    "dec %0\n\t"
                    "jne loop\n"
                    : /* No Outputs */
                    : "r"(bytes),"r"(value),"r"(&value)
                    : "memory");
#endif
   }
}