diff options
| -rw-r--r-- | clippy_lints/src/arithmetic.rs | 18 | ||||
| -rw-r--r-- | src/lintlist/mod.rs | 2 | ||||
| -rw-r--r-- | tests/ui/integer_arithmetic.rs | 10 | ||||
| -rw-r--r-- | tests/ui/integer_arithmetic.stderr | 40 |
4 files changed, 48 insertions, 22 deletions
diff --git a/clippy_lints/src/arithmetic.rs b/clippy_lints/src/arithmetic.rs index a138c9d3545..6cbe10a5352 100644 --- a/clippy_lints/src/arithmetic.rs +++ b/clippy_lints/src/arithmetic.rs @@ -6,11 +6,17 @@ use rustc_session::{declare_tool_lint, impl_lint_pass}; use rustc_span::source_map::Span; declare_clippy_lint! { - /// **What it does:** Checks for plain integer arithmetic. + /// **What it does:** Checks for integer arithmetic operations which could overflow or panic. /// - /// **Why is this bad?** This is only checked against overflow in debug builds. - /// In some applications one wants explicitly checked, wrapping or saturating - /// arithmetic. + /// Specifically, checks for any operators (`+`, `-`, `*`, `<<`, etc) which are capable + /// of overflowing according to the [Rust + /// Reference](https://doc.rust-lang.org/reference/expressions/operator-expr.html#overflow), + /// or which can panic (`/`, `%`). No bounds analysis or sophisticated reasoning is + /// attempted. + /// + /// **Why is this bad?** Integer overflow will trigger a panic in debug builds or will wrap in + /// release mode. Division by zero will cause a panic in either mode. In some applications one + /// wants explicitly checked, wrapping or saturating arithmetic. /// /// **Known problems:** None. /// @@ -21,7 +27,7 @@ declare_clippy_lint! { /// ``` pub INTEGER_ARITHMETIC, restriction, - "any integer arithmetic statement" + "any integer arithmetic expression which could overflow or panic" } declare_clippy_lint! { @@ -71,8 +77,6 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Arithmetic { | hir::BinOpKind::BitAnd | hir::BinOpKind::BitOr | hir::BinOpKind::BitXor - | hir::BinOpKind::Shl - | hir::BinOpKind::Shr | hir::BinOpKind::Eq | hir::BinOpKind::Lt | hir::BinOpKind::Le diff --git a/src/lintlist/mod.rs b/src/lintlist/mod.rs index ca1faf6cfb7..d4602a3ad8e 100644 --- a/src/lintlist/mod.rs +++ b/src/lintlist/mod.rs @@ -853,7 +853,7 @@ pub static ref ALL_LINTS: Vec<Lint> = vec![ Lint { name: "integer_arithmetic", group: "restriction", - desc: "any integer arithmetic statement", + desc: "any integer arithmetic expression which could overflow or panic", deprecation: None, module: "arithmetic", }, diff --git a/tests/ui/integer_arithmetic.rs b/tests/ui/integer_arithmetic.rs index 2fe32c6ace8..7b1b64f390a 100644 --- a/tests/ui/integer_arithmetic.rs +++ b/tests/ui/integer_arithmetic.rs @@ -17,6 +17,8 @@ fn main() { i / 2; // no error, this is part of the expression in the preceding line i - 2 + 2 - i; -i; + i >> 1; + i << 1; // no error, overflows are checked by `overflowing_literals` -1; @@ -25,18 +27,16 @@ fn main() { i & 1; // no wrapping i | 1; i ^ 1; - i >> 1; - i << 1; i += 1; i -= 1; i *= 2; i /= 2; i %= 2; - - // no errors i <<= 3; i >>= 2; + + // no errors i |= 1; i &= 1; i ^= i; @@ -72,8 +72,6 @@ fn main() { 1 + 1 }; } - - } // warn on references as well! (#5328) diff --git a/tests/ui/integer_arithmetic.stderr b/tests/ui/integer_arithmetic.stderr index 64c44d7ecc7..83e8a9cde3f 100644 --- a/tests/ui/integer_arithmetic.stderr +++ b/tests/ui/integer_arithmetic.stderr @@ -32,6 +32,18 @@ LL | -i; | ^^ error: integer arithmetic detected + --> $DIR/integer_arithmetic.rs:20:5 + | +LL | i >> 1; + | ^^^^^^ + +error: integer arithmetic detected + --> $DIR/integer_arithmetic.rs:21:5 + | +LL | i << 1; + | ^^^^^^ + +error: integer arithmetic detected --> $DIR/integer_arithmetic.rs:31:5 | LL | i += 1; @@ -62,46 +74,58 @@ LL | i %= 2; | ^^^^^^ error: integer arithmetic detected - --> $DIR/integer_arithmetic.rs:81:5 + --> $DIR/integer_arithmetic.rs:36:5 + | +LL | i <<= 3; + | ^^^^^^^ + +error: integer arithmetic detected + --> $DIR/integer_arithmetic.rs:37:5 + | +LL | i >>= 2; + | ^^^^^^^ + +error: integer arithmetic detected + --> $DIR/integer_arithmetic.rs:79:5 | LL | 3 + &1; | ^^^^^^ error: integer arithmetic detected - --> $DIR/integer_arithmetic.rs:82:5 + --> $DIR/integer_arithmetic.rs:80:5 | LL | &3 + 1; | ^^^^^^ error: integer arithmetic detected - --> $DIR/integer_arithmetic.rs:83:5 + --> $DIR/integer_arithmetic.rs:81:5 | LL | &3 + &1; | ^^^^^^^ error: integer arithmetic detected - --> $DIR/integer_arithmetic.rs:88:5 + --> $DIR/integer_arithmetic.rs:86:5 | LL | a + x | ^^^^^ error: integer arithmetic detected - --> $DIR/integer_arithmetic.rs:92:5 + --> $DIR/integer_arithmetic.rs:90:5 | LL | x + y | ^^^^^ error: integer arithmetic detected - --> $DIR/integer_arithmetic.rs:96:5 + --> $DIR/integer_arithmetic.rs:94:5 | LL | x + y | ^^^^^ error: integer arithmetic detected - --> $DIR/integer_arithmetic.rs:100:5 + --> $DIR/integer_arithmetic.rs:98:5 | LL | (&x + &y) | ^^^^^^^^^ -error: aborting due to 17 previous errors +error: aborting due to 21 previous errors |