size_t jsuGetFreeStack() {
#ifdef ARM
  void *frame = __builtin_frame_address(0);
  size_t stackPos = (size_t)((char*)frame);
  size_t stackEnd = (size_t)((char*)&LINKER_END_VAR);
  if (stackPos < stackEnd) return 0; // should never happen, but just in case of overflow!
  return  stackPos - stackEnd;
#elif defined(LINUX)
  // On linux, we set STACK_BASE from `main`.
  char ptr; // this is on the stack
  extern void *STACK_BASE;
  uint32_t count =  (uint32_t)((size_t)STACK_BASE - (size_t)&ptr);
  const uint32_t max_stack = 1000000; // give it 1 megabyte of stack
  if (count>max_stack) return 0;
  return max_stack - count;
#else
  // stack depth seems pretty platform-specific :( Default to a value that disables it
  return 1000000; // no stack depth check on this platform
#endif
}
The software performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control.