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##Lints
-There are 130 lints included in this crate:
+There are 131 lints included in this crate:
name | default | meaning
---------------------------------------------------------------------------------------------------------------------|---------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
[option_unwrap_used](https://github.com/Manishearth/rust-clippy/wiki#option_unwrap_used) | allow | using `Option.unwrap()`, which should at least get a better message using `expect()`
[or_fun_call](https://github.com/Manishearth/rust-clippy/wiki#or_fun_call) | warn | using any `*or` method when the `*or_else` would do
[out_of_bounds_indexing](https://github.com/Manishearth/rust-clippy/wiki#out_of_bounds_indexing) | deny | out of bound constant indexing
+[overflow_check_conditional](https://github.com/Manishearth/rust-clippy/wiki#overflow_check_conditional) | warn | Using overflow checks which are likely to panic
[panic_params](https://github.com/Manishearth/rust-clippy/wiki#panic_params) | warn | missing parameters in `panic!`
[precedence](https://github.com/Manishearth/rust-clippy/wiki#precedence) | warn | catches operations where precedence may be unclear. See the wiki for a list of cases caught
[print_stdout](https://github.com/Manishearth/rust-clippy/wiki#print_stdout) | allow | printing on stdout
pub mod needless_update;
pub mod no_effect;
pub mod open_options;
+pub mod overflow_check_conditional;
pub mod panic;
pub mod precedence;
pub mod print;
reg.register_early_lint_pass(box formatting::Formatting);
reg.register_late_lint_pass(box swap::Swap);
reg.register_early_lint_pass(box if_not_else::IfNotElse);
+ reg.register_late_lint_pass(box overflow_check_conditional::OverflowCheckConditional);
reg.register_lint_group("clippy_pedantic", vec![
enum_glob_use::ENUM_GLOB_USE,
needless_update::NEEDLESS_UPDATE,
no_effect::NO_EFFECT,
open_options::NONSENSICAL_OPEN_OPTIONS,
+ overflow_check_conditional::OVERFLOW_CHECK_CONDITIONAL,
panic::PANIC_PARAMS,
precedence::PRECEDENCE,
ptr_arg::PTR_ARG,
--- /dev/null
+use rustc::lint::*;
+use rustc_front::hir::*;
+use utils::{span_lint};
+
+/// **What it does:** This lint finds classic overflow checks.
+///
+/// **Why is this bad?** Most classic C overflow checks will fail in Rust. Users can use functions like `overflowing_*` and `wrapping_*` instead.
+///
+/// **Known problems:** None.
+///
+/// **Example:** `a + b < a`
+declare_lint!(pub OVERFLOW_CHECK_CONDITIONAL, Warn,
+ "Using overflow checks which are likely to panic");
+
+#[derive(Copy, Clone)]
+pub struct OverflowCheckConditional;
+
+impl LintPass for OverflowCheckConditional {
+ fn get_lints(&self) -> LintArray {
+ lint_array!(OVERFLOW_CHECK_CONDITIONAL)
+ }
+}
+
+impl LateLintPass for OverflowCheckConditional {
+ fn check_expr(&mut self, cx: &LateContext, expr: &Expr) {
+ if_let_chain! {[
+ let Expr_::ExprBinary(ref op, ref first, ref second) = expr.node,
+ let BinOp_::BiLt = op.node,
+ let Expr_::ExprBinary(ref op2, ref add1, ref add2) = first.node,
+ let BinOp_::BiAdd = op2.node,
+ let Expr_::ExprPath(_,ref path1) = add1.node,
+ let Expr_::ExprPath(_, ref path2) = add2.node,
+ let Expr_::ExprPath(_, ref path3) = second.node,
+ (&path1.segments[0]).identifier == (&path3.segments[0]).identifier || (&path2.segments[0]).identifier == (&path3.segments[0]).identifier,
+ cx.tcx.expr_ty(add1).is_integral(),
+ cx.tcx.expr_ty(add2).is_integral()
+ ], {
+ span_lint(cx, OVERFLOW_CHECK_CONDITIONAL, expr.span, "You are trying to use classic C overflow conditons that will fail in Rust.");
+ }}
+ }
+}