45 lines
1.6 KiB
Rust
45 lines
1.6 KiB
Rust
use crate::utils::{match_def_path, paths, qpath_res, span_lint};
|
|
use rustc::hir::{Expr, ExprKind};
|
|
use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
|
|
use rustc::{declare_lint_pass, declare_tool_lint};
|
|
|
|
declare_clippy_lint! {
|
|
/// **What it does:** Checks for usage of `std::mem::forget(t)` where `t` is
|
|
/// `Drop`.
|
|
///
|
|
/// **Why is this bad?** `std::mem::forget(t)` prevents `t` from running its
|
|
/// destructor, possibly causing leaks.
|
|
///
|
|
/// **Known problems:** None.
|
|
///
|
|
/// **Example:**
|
|
/// ```rust
|
|
/// # use std::mem;
|
|
/// # use std::rc::Rc;
|
|
/// mem::forget(Rc::new(55))
|
|
/// ```
|
|
pub MEM_FORGET,
|
|
restriction,
|
|
"`mem::forget` usage on `Drop` types, likely to cause memory leaks"
|
|
}
|
|
|
|
declare_lint_pass!(MemForget => [MEM_FORGET]);
|
|
|
|
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MemForget {
|
|
fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, e: &'tcx Expr) {
|
|
if let ExprKind::Call(ref path_expr, ref args) = e.node {
|
|
if let ExprKind::Path(ref qpath) = path_expr.node {
|
|
if let Some(def_id) = qpath_res(cx, qpath, path_expr.hir_id).opt_def_id() {
|
|
if match_def_path(cx, def_id, &paths::MEM_FORGET) {
|
|
let forgot_ty = cx.tables.expr_ty(&args[0]);
|
|
|
|
if forgot_ty.ty_adt_def().map_or(false, |def| def.has_dtor(cx.tcx)) {
|
|
span_lint(cx, MEM_FORGET, e.span, "usage of mem::forget on Drop type");
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|