error: the operation is ineffective. Consider reducing it to `x`
  --> $DIR/identity_op.rs:13:5
   |
13 |     x + 0;
   |     ^^^^^
   |
   = note: `-D identity-op` implied by `-D warnings`

error: the operation is ineffective. Consider reducing it to `x`
  --> $DIR/identity_op.rs:14:5
   |
14 |     x + (1 - 1);
   |     ^^^^^^^^^^^

error: the operation is ineffective. Consider reducing it to `x`
  --> $DIR/identity_op.rs:16:5
   |
16 |     0 + x;
   |     ^^^^^

error: the operation is ineffective. Consider reducing it to `x`
  --> $DIR/identity_op.rs:19:5
   |
19 |     x | (0);
   |     ^^^^^^^

error: the operation is ineffective. Consider reducing it to `x`
  --> $DIR/identity_op.rs:22:5
   |
22 |     x * 1;
   |     ^^^^^

error: the operation is ineffective. Consider reducing it to `x`
  --> $DIR/identity_op.rs:23:5
   |
23 |     1 * x;
   |     ^^^^^

error: the operation is ineffective. Consider reducing it to `x`
  --> $DIR/identity_op.rs:29:5
   |
29 |     -1 & x;
   |     ^^^^^^

error: the operation is ineffective. Consider reducing it to `u`
  --> $DIR/identity_op.rs:32:5
   |
32 |     u & 255;
   |     ^^^^^^^

error: aborting due to 8 previous errors