const THREE_BITS : i64 = 7;
const EVEN_MORE_REDIRECTION : i64 = THREE_BITS;
#[warn(bad_bit_mask)]
#[allow(ineffective_bit_mask, identity_op, no_effect, unnecessary_operation)]
fn main() {
let x = 5;
x & 0 == 0;
x & 1 == 1; //ok, distinguishes bit 0
x & 1 == 0; //ok, compared with zero
x & 2 == 1;
x | 0 == 0; //ok, equals x == 0 (maybe warn?)
x | 1 == 3; //ok, equals x == 2 || x == 3
x | 3 == 3; //ok, equals x <= 3
x | 3 == 2;
x & 1 > 1;
x & 2 > 1; // ok, distinguishes x & 2 == 2 from x & 2 == 0
x & 2 < 1; // ok, distinguishes x & 2 == 2 from x & 2 == 0
x | 1 > 1; // ok (if a bit silly), equals x > 1
x | 2 > 1;
x | 2 <= 2; // ok (if a bit silly), equals x <= 2
x & 192 == 128; // ok, tests for bit 7 and not bit 6
x & 0xffc0 == 0xfe80; // ok
// this also now works with constants
x & THREE_BITS == 8;
x | EVEN_MORE_REDIRECTION < 7;
0 & x == 0;
1 | x > 1;
// and should now also match uncommon usage
1 < 2 | x;
2 == 3 | x;
1 == x & 2;
x | 1 > 2; // no error, because we allowed ineffective bit masks
ineffective();
}
#[warn(ineffective_bit_mask)]
#[allow(bad_bit_mask, no_effect, unnecessary_operation)]
fn ineffective() {
let x = 5;
x | 1 > 3;
x | 1 < 4;
x | 1 <= 3;
x | 1 >= 8;
x | 1 > 2; // not an error (yet), better written as x >= 2
x | 1 >= 7; // not an error (yet), better written as x >= 6
x | 3 > 4; // not an error (yet), better written as x >= 4
x | 4 <= 19;
}