1 const THREE_BITS: i64 = 7;
2 const EVEN_MORE_REDIRECTION: i64 = THREE_BITS;
3
4 #[warn(clippy::bad_bit_mask)]
5 #[allow(
6 clippy::ineffective_bit_mask,
7 clippy::identity_op,
8 clippy::no_effect,
9 clippy::unnecessary_operation
10 )]
main()11 fn main() {
12 let x = 5;
13
14 x & 0 == 0;
15 x & 1 == 1; //ok, distinguishes bit 0
16 x & 1 == 0; //ok, compared with zero
17 x & 2 == 1;
18 x | 0 == 0; //ok, equals x == 0 (maybe warn?)
19 x | 1 == 3; //ok, equals x == 2 || x == 3
20 x | 3 == 3; //ok, equals x <= 3
21 x | 3 == 2;
22
23 x & 1 > 1;
24 x & 2 > 1; // ok, distinguishes x & 2 == 2 from x & 2 == 0
25 x & 2 < 1; // ok, distinguishes x & 2 == 2 from x & 2 == 0
26 x | 1 > 1; // ok (if a bit silly), equals x > 1
27 x | 2 > 1;
28 x | 2 <= 2; // ok (if a bit silly), equals x <= 2
29
30 x & 192 == 128; // ok, tests for bit 7 and not bit 6
31 x & 0xffc0 == 0xfe80; // ok
32
33 // this also now works with constants
34 x & THREE_BITS == 8;
35 x | EVEN_MORE_REDIRECTION < 7;
36
37 0 & x == 0;
38 1 | x > 1;
39
40 // and should now also match uncommon usage
41 1 < 2 | x;
42 2 == 3 | x;
43 1 == x & 2;
44
45 x | 1 > 2; // no error, because we allowed ineffective bit masks
46 ineffective();
47 }
48
49 #[warn(clippy::ineffective_bit_mask)]
50 #[allow(clippy::bad_bit_mask, clippy::no_effect, clippy::unnecessary_operation)]
ineffective()51 fn ineffective() {
52 let x = 5;
53
54 x | 1 > 3;
55 x | 1 < 4;
56 x | 1 <= 3;
57 x | 1 >= 8;
58
59 x | 1 > 2; // not an error (yet), better written as x >= 2
60 x | 1 >= 7; // not an error (yet), better written as x >= 6
61 x | 3 > 4; // not an error (yet), better written as x >= 4
62 x | 4 <= 19;
63 }
64