1.2.2.4. alpha.core.Conversion (C, C++, ObjC)
Loss of sign/precision in implicit conversions.

Examples:

void test(unsigned U, signed S) {
  if (S > 10) {
    if (U < S) {
    }
  }
  if (S < -10) {
    if (U < S) { // warn (loss of sign)
    }
  }
}

void test() {
  long long A = 1LL << 60;
  short X = A; // warn (loss of precision)
}