diff options
| -rw-r--r-- | clippy_lints/src/operators/arithmetic_side_effects.rs | 12 | ||||
| -rw-r--r-- | tests/ui/arithmetic_side_effects.rs | 4 | ||||
| -rw-r--r-- | tests/ui/arithmetic_side_effects.stderr | 14 |
3 files changed, 27 insertions, 3 deletions
diff --git a/clippy_lints/src/operators/arithmetic_side_effects.rs b/clippy_lints/src/operators/arithmetic_side_effects.rs index 25e8de94863..e5713735672 100644 --- a/clippy_lints/src/operators/arithmetic_side_effects.rs +++ b/clippy_lints/src/operators/arithmetic_side_effects.rs @@ -154,10 +154,18 @@ impl ArithmeticSideEffects { Self::literal_integer(cx, actual_rhs), ) { (None, None) => false, - (None, Some(n)) | (Some(n), None) => match (&op.node, n) { + (None, Some(n)) => match (&op.node, n) { // Division and module are always valid if applied to non-zero integers (hir::BinOpKind::Div | hir::BinOpKind::Rem, local_n) if local_n != 0 => true, - // Addition or subtracting zeros is always a no-op + // Adding or subtracting zeros is always a no-op + (hir::BinOpKind::Add | hir::BinOpKind::Sub, 0) + // Multiplication by 1 or 0 will never overflow + | (hir::BinOpKind::Mul, 0 | 1) + => true, + _ => false, + }, + (Some(n), None) => match (&op.node, n) { + // Adding or subtracting zeros is always a no-op (hir::BinOpKind::Add | hir::BinOpKind::Sub, 0) // Multiplication by 1 or 0 will never overflow | (hir::BinOpKind::Mul, 0 | 1) diff --git a/tests/ui/arithmetic_side_effects.rs b/tests/ui/arithmetic_side_effects.rs index ee7d2ba444b..3c06676d722 100644 --- a/tests/ui/arithmetic_side_effects.rs +++ b/tests/ui/arithmetic_side_effects.rs @@ -425,4 +425,8 @@ pub fn integer_arithmetic() { i ^= i; } +pub fn issue_10583(a: u16) -> u16 { + 10 / a +} + fn main() {} diff --git a/tests/ui/arithmetic_side_effects.stderr b/tests/ui/arithmetic_side_effects.stderr index 3895f08964c..2c8ee2884e7 100644 --- a/tests/ui/arithmetic_side_effects.stderr +++ b/tests/ui/arithmetic_side_effects.stderr @@ -577,6 +577,12 @@ LL | i * 2; | ^^^^^ error: arithmetic operation that can potentially result in unexpected side-effects + --> $DIR/arithmetic_side_effects.rs:394:5 + | +LL | 1 % i / 2; + | ^^^^^ + +error: arithmetic operation that can potentially result in unexpected side-effects --> $DIR/arithmetic_side_effects.rs:395:5 | LL | i - 2 + 2 - i; @@ -642,5 +648,11 @@ error: arithmetic operation that can potentially result in unexpected side-effec LL | i %= var2; | ^^^^^^^^^ -error: aborting due to 107 previous errors +error: arithmetic operation that can potentially result in unexpected side-effects + --> $DIR/arithmetic_side_effects.rs:429:5 + | +LL | 10 / a + | ^^^^^^ + +error: aborting due to 109 previous errors |