1.2.1.1. alpha.clone.CloneChecker (C, C++, ObjC)
Reports similar pieces of code.

Examples:

void log();

int max(int a, int b) { // warn
  log();
  if (a > b)
    return a;
  return b;
}

int maxClone(int x, int y) { // similar code here
  log();
  if (x > y)
    return x;
  return y;
}