From f33bb3d900f93b13f4a9060e0060df36ff3a7e3d Mon Sep 17 00:00:00 2001 From: Yoshitomo Nakanishi Date: Tue, 9 Mar 2021 17:22:21 +0900 Subject: [PATCH] Move cast_ref_to_mut to its own module --- clippy_lints/src/casts/cast_ref_to_mut.rs | 28 ++++++ clippy_lints/src/casts/mod.rs | 107 +++++++++------------- clippy_lints/src/lib.rs | 1 - 3 files changed, 72 insertions(+), 64 deletions(-) create mode 100644 clippy_lints/src/casts/cast_ref_to_mut.rs diff --git a/clippy_lints/src/casts/cast_ref_to_mut.rs b/clippy_lints/src/casts/cast_ref_to_mut.rs new file mode 100644 index 00000000000..3fdc1c6168b --- /dev/null +++ b/clippy_lints/src/casts/cast_ref_to_mut.rs @@ -0,0 +1,28 @@ +use rustc_hir::{Expr, ExprKind, MutTy, Mutability, TyKind, UnOp}; +use rustc_lint::LateContext; +use rustc_middle::ty; + +use if_chain::if_chain; + +use crate::utils::span_lint; + +use super::CAST_REF_TO_MUT; + +pub(super) fn check(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { + if_chain! { + if let ExprKind::Unary(UnOp::Deref, e) = &expr.kind; + if let ExprKind::Cast(e, t) = &e.kind; + if let TyKind::Ptr(MutTy { mutbl: Mutability::Mut, .. }) = t.kind; + if let ExprKind::Cast(e, t) = &e.kind; + if let TyKind::Ptr(MutTy { mutbl: Mutability::Not, .. }) = t.kind; + if let ty::Ref(..) = cx.typeck_results().node_type(e.hir_id).kind(); + then { + span_lint( + cx, + CAST_REF_TO_MUT, + expr.span, + "casting `&T` to `&mut T` may cause undefined behavior, consider instead using an `UnsafeCell`", + ); + } + } +} diff --git a/clippy_lints/src/casts/mod.rs b/clippy_lints/src/casts/mod.rs index cf8a64e1fd8..7d5ada18be3 100644 --- a/clippy_lints/src/casts/mod.rs +++ b/clippy_lints/src/casts/mod.rs @@ -3,6 +3,7 @@ mod cast_possible_wrap; mod cast_precision_loss; mod cast_ptr_alignment; +mod cast_ref_to_mut; mod cast_sign_loss; mod fn_to_numeric_cast; mod fn_to_numeric_cast_with_truncation; @@ -14,7 +15,7 @@ use if_chain::if_chain; use rustc_ast::LitKind; use rustc_errors::Applicability; -use rustc_hir::{Expr, ExprKind, MutTy, Mutability, TyKind, UnOp}; +use rustc_hir::{Expr, ExprKind, Mutability, TyKind}; use rustc_lint::{LateContext, LateLintPass, LintContext}; use rustc_middle::lint::in_external_macro; use rustc_middle::ty::{self, TypeAndMut, UintTy}; @@ -23,7 +24,7 @@ use crate::utils::sugg::Sugg; use crate::utils::{ - is_hir_ty_cfg_dependant, meets_msrv, snippet_with_applicability, span_lint, span_lint_and_sugg, span_lint_and_then, + is_hir_ty_cfg_dependant, meets_msrv, snippet_with_applicability, span_lint_and_sugg, span_lint_and_then, }; declare_clippy_lint! { @@ -255,51 +256,6 @@ "casting a function pointer to a numeric type not wide enough to store the address" } -declare_lint_pass!(Casts => [ - CAST_PRECISION_LOSS, - CAST_SIGN_LOSS, - CAST_POSSIBLE_TRUNCATION, - CAST_POSSIBLE_WRAP, - CAST_LOSSLESS, - UNNECESSARY_CAST, - CAST_PTR_ALIGNMENT, - FN_TO_NUMERIC_CAST, - FN_TO_NUMERIC_CAST_WITH_TRUNCATION, -]); - -impl<'tcx> LateLintPass<'tcx> for Casts { - fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { - if expr.span.from_expansion() { - return; - } - if let ExprKind::Cast(ref cast_expr, cast_to) = expr.kind { - if is_hir_ty_cfg_dependant(cx, cast_to) { - return; - } - let (cast_from, cast_to) = ( - cx.typeck_results().expr_ty(cast_expr), - cx.typeck_results().expr_ty(expr), - ); - - if unnecessary_cast::check(cx, expr, cast_expr, cast_from, cast_to) { - return; - } - - fn_to_numeric_cast::check(cx, expr, cast_expr, cast_from, cast_to); - fn_to_numeric_cast_with_truncation::check(cx, expr, cast_expr, cast_from, cast_to); - if cast_from.is_numeric() && cast_to.is_numeric() && !in_external_macro(cx.sess(), expr.span) { - cast_possible_truncation::check(cx, expr, cast_from, cast_to); - cast_possible_wrap::check(cx, expr, cast_from, cast_to); - cast_precision_loss::check(cx, expr, cast_from, cast_to); - cast_lossless::check(cx, expr, cast_expr, cast_from, cast_to); - cast_sign_loss::check(cx, expr, cast_expr, cast_from, cast_to); - } - } - - cast_ptr_alignment::check(cx, expr); - } -} - declare_clippy_lint! { /// **What it does:** Checks for casts of `&T` to `&mut T` anywhere in the code. /// @@ -334,26 +290,51 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { "a cast of reference to a mutable pointer" } -declare_lint_pass!(RefToMut => [CAST_REF_TO_MUT]); +declare_lint_pass!(Casts => [ + CAST_PRECISION_LOSS, + CAST_SIGN_LOSS, + CAST_POSSIBLE_TRUNCATION, + CAST_POSSIBLE_WRAP, + CAST_LOSSLESS, + CAST_REF_TO_MUT, + UNNECESSARY_CAST, + CAST_PTR_ALIGNMENT, + FN_TO_NUMERIC_CAST, + FN_TO_NUMERIC_CAST_WITH_TRUNCATION, +]); -impl<'tcx> LateLintPass<'tcx> for RefToMut { +impl<'tcx> LateLintPass<'tcx> for Casts { fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { - if_chain! { - if let ExprKind::Unary(UnOp::Deref, e) = &expr.kind; - if let ExprKind::Cast(e, t) = &e.kind; - if let TyKind::Ptr(MutTy { mutbl: Mutability::Mut, .. }) = t.kind; - if let ExprKind::Cast(e, t) = &e.kind; - if let TyKind::Ptr(MutTy { mutbl: Mutability::Not, .. }) = t.kind; - if let ty::Ref(..) = cx.typeck_results().node_type(e.hir_id).kind(); - then { - span_lint( - cx, - CAST_REF_TO_MUT, - expr.span, - "casting `&T` to `&mut T` may cause undefined behavior, consider instead using an `UnsafeCell`", - ); + cast_ref_to_mut::check(cx, expr); + + if expr.span.from_expansion() { + return; + } + if let ExprKind::Cast(ref cast_expr, cast_to) = expr.kind { + if is_hir_ty_cfg_dependant(cx, cast_to) { + return; + } + let (cast_from, cast_to) = ( + cx.typeck_results().expr_ty(cast_expr), + cx.typeck_results().expr_ty(expr), + ); + + if unnecessary_cast::check(cx, expr, cast_expr, cast_from, cast_to) { + return; + } + + fn_to_numeric_cast::check(cx, expr, cast_expr, cast_from, cast_to); + fn_to_numeric_cast_with_truncation::check(cx, expr, cast_expr, cast_from, cast_to); + if cast_from.is_numeric() && cast_to.is_numeric() && !in_external_macro(cx.sess(), expr.span) { + cast_possible_truncation::check(cx, expr, cast_from, cast_to); + cast_possible_wrap::check(cx, expr, cast_from, cast_to); + cast_precision_loss::check(cx, expr, cast_from, cast_to); + cast_lossless::check(cx, expr, cast_expr, cast_from, cast_to); + cast_sign_loss::check(cx, expr, cast_expr, cast_from, cast_to); } } + + cast_ptr_alignment::check(cx, expr); } } diff --git a/clippy_lints/src/lib.rs b/clippy_lints/src/lib.rs index a46c56a01d5..47afd7beb74 100644 --- a/clippy_lints/src/lib.rs +++ b/clippy_lints/src/lib.rs @@ -1176,7 +1176,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf: store.register_late_pass(|| box slow_vector_initialization::SlowVectorInit); store.register_late_pass(|| box unnecessary_sort_by::UnnecessarySortBy); store.register_late_pass(|| box unnecessary_wraps::UnnecessaryWraps); - store.register_late_pass(|| box casts::RefToMut); store.register_late_pass(|| box assertions_on_constants::AssertionsOnConstants); store.register_late_pass(|| box transmuting_null::TransmutingNull); store.register_late_pass(|| box path_buf_push_overwrite::PathBufPushOverwrite);