100 lines
2.9 KiB
Rust
100 lines
2.9 KiB
Rust
use clippy_utils::diagnostics::span_lint_and_sugg;
|
|
use clippy_utils::is_no_std_crate;
|
|
use clippy_utils::source::snippet_opt;
|
|
use clippy_utils::{meets_msrv, msrvs};
|
|
use if_chain::if_chain;
|
|
use rustc_errors::Applicability;
|
|
use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, TyKind};
|
|
use rustc_lint::{LateContext, LateLintPass};
|
|
use rustc_semver::RustcVersion;
|
|
use rustc_session::{declare_tool_lint, impl_lint_pass};
|
|
|
|
declare_clippy_lint! {
|
|
/// ### What it does
|
|
/// Checks for the usage of `&expr as *const T` or
|
|
/// `&mut expr as *mut T`, and suggest using `ptr::addr_of` or
|
|
/// `ptr::addr_of_mut` instead.
|
|
///
|
|
/// ### Why is this bad?
|
|
/// This would improve readability and avoid creating a reference
|
|
/// that points to an uninitialized value or unaligned place.
|
|
/// Read the `ptr::addr_of` docs for more information.
|
|
///
|
|
/// ### Example
|
|
/// ```rust
|
|
/// let val = 1;
|
|
/// let p = &val as *const i32;
|
|
///
|
|
/// let mut val_mut = 1;
|
|
/// let p_mut = &mut val_mut as *mut i32;
|
|
/// ```
|
|
/// Use instead:
|
|
/// ```rust
|
|
/// let val = 1;
|
|
/// let p = std::ptr::addr_of!(val);
|
|
///
|
|
/// let mut val_mut = 1;
|
|
/// let p_mut = std::ptr::addr_of_mut!(val_mut);
|
|
/// ```
|
|
#[clippy::version = "1.60.0"]
|
|
pub BORROW_AS_PTR,
|
|
pedantic,
|
|
"borrowing just to cast to a raw pointer"
|
|
}
|
|
|
|
impl_lint_pass!(BorrowAsPtr => [BORROW_AS_PTR]);
|
|
|
|
pub struct BorrowAsPtr {
|
|
msrv: Option<RustcVersion>,
|
|
}
|
|
|
|
impl BorrowAsPtr {
|
|
#[must_use]
|
|
pub fn new(msrv: Option<RustcVersion>) -> Self {
|
|
Self { msrv }
|
|
}
|
|
}
|
|
|
|
impl<'tcx> LateLintPass<'tcx> for BorrowAsPtr {
|
|
fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
|
|
if !meets_msrv(self.msrv.as_ref(), &msrvs::BORROW_AS_PTR) {
|
|
return;
|
|
}
|
|
|
|
if expr.span.from_expansion() {
|
|
return;
|
|
}
|
|
|
|
if_chain! {
|
|
if let ExprKind::Cast(left_expr, ty) = &expr.kind;
|
|
if let TyKind::Ptr(_) = ty.kind;
|
|
if let ExprKind::AddrOf(BorrowKind::Ref, mutability, e) = &left_expr.kind;
|
|
|
|
then {
|
|
let core_or_std = if is_no_std_crate(cx) { "core" } else { "std" };
|
|
let macro_name = match mutability {
|
|
Mutability::Not => "addr_of",
|
|
Mutability::Mut => "addr_of_mut",
|
|
};
|
|
|
|
span_lint_and_sugg(
|
|
cx,
|
|
BORROW_AS_PTR,
|
|
expr.span,
|
|
"borrow as raw pointer",
|
|
"try",
|
|
format!(
|
|
"{}::ptr::{}!({})",
|
|
core_or_std,
|
|
macro_name,
|
|
snippet_opt(cx, e.span).unwrap()
|
|
),
|
|
Applicability::MachineApplicable,
|
|
);
|
|
}
|
|
}
|
|
}
|
|
|
|
extract_msrv_attr!(LateContext);
|
|
}
|