What is the issue with this static variable assignment to a pointer in local function?

Question

int* func(int *ptr)
{
  static int a = 5;
  ptr = &a;
  return ptr;
}

Someone asked me this question in an interview. Now the point is, the variable 'a' is static, so, unlike ordinary variables which are declared, which loses it's value (popped from stack) once the function returns, this variable retains it's value as it is a static one.

Then i didn't understand, what's the issue with this piece of code?

Answer 1

There is no point in having ptr as a parameter. The passed value is not used. You could change this to

int* func()
{
  static int a = 5;
  return &a;
}