Auto merge of #7682 - Qwaz:uninit_vec, r=xFrednet
Implement uninit_vec lint changelog: add the new lint [`uninit_vec`] Fix #7681
This commit is contained in:
commit
3d9c4a655b
@ -3039,6 +3039,7 @@ Released 2018-09-13
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[`unicode_not_nfc`]: https://rust-lang.github.io/rust-clippy/master/index.html#unicode_not_nfc
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[`unimplemented`]: https://rust-lang.github.io/rust-clippy/master/index.html#unimplemented
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[`uninit_assumed_init`]: https://rust-lang.github.io/rust-clippy/master/index.html#uninit_assumed_init
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[`uninit_vec`]: https://rust-lang.github.io/rust-clippy/master/index.html#uninit_vec
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[`unit_arg`]: https://rust-lang.github.io/rust-clippy/master/index.html#unit_arg
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[`unit_cmp`]: https://rust-lang.github.io/rust-clippy/master/index.html#unit_cmp
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[`unit_return_expecting_ord`]: https://rust-lang.github.io/rust-clippy/master/index.html#unit_return_expecting_ord
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@ -279,6 +279,7 @@
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LintId::of(types::VEC_BOX),
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LintId::of(undropped_manually_drops::UNDROPPED_MANUALLY_DROPS),
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LintId::of(unicode::INVISIBLE_CHARACTERS),
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LintId::of(uninit_vec::UNINIT_VEC),
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LintId::of(unit_return_expecting_ord::UNIT_RETURN_EXPECTING_ORD),
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LintId::of(unit_types::UNIT_ARG),
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LintId::of(unit_types::UNIT_CMP),
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@ -64,6 +64,7 @@
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LintId::of(transmuting_null::TRANSMUTING_NULL),
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LintId::of(undropped_manually_drops::UNDROPPED_MANUALLY_DROPS),
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LintId::of(unicode::INVISIBLE_CHARACTERS),
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LintId::of(uninit_vec::UNINIT_VEC),
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LintId::of(unit_return_expecting_ord::UNIT_RETURN_EXPECTING_ORD),
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LintId::of(unit_types::UNIT_CMP),
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LintId::of(unnamed_address::FN_ADDRESS_COMPARISONS),
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@ -471,6 +471,7 @@
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unicode::INVISIBLE_CHARACTERS,
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unicode::NON_ASCII_LITERAL,
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unicode::UNICODE_NOT_NFC,
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uninit_vec::UNINIT_VEC,
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unit_return_expecting_ord::UNIT_RETURN_EXPECTING_ORD,
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unit_types::LET_UNIT_VALUE,
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unit_types::UNIT_ARG,
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@ -362,6 +362,7 @@ macro_rules! declare_clippy_lint {
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mod undocumented_unsafe_blocks;
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mod undropped_manually_drops;
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mod unicode;
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mod uninit_vec;
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mod unit_return_expecting_ord;
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mod unit_types;
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mod unnamed_address;
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@ -519,6 +520,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
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store.register_late_pass(|| Box::new(blocks_in_if_conditions::BlocksInIfConditions));
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store.register_late_pass(|| Box::new(collapsible_match::CollapsibleMatch));
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store.register_late_pass(|| Box::new(unicode::Unicode));
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store.register_late_pass(|| Box::new(uninit_vec::UninitVec));
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store.register_late_pass(|| Box::new(unit_return_expecting_ord::UnitReturnExpectingOrd));
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store.register_late_pass(|| Box::new(strings::StringAdd));
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store.register_late_pass(|| Box::new(implicit_return::ImplicitReturn));
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@ -1,9 +1,8 @@
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use clippy_utils::diagnostics::span_lint;
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use clippy_utils::{is_expr_path_def_path, match_def_path, paths};
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use clippy_utils::{is_expr_path_def_path, paths, ty::is_uninit_value_valid_for_ty};
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use if_chain::if_chain;
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use rustc_hir as hir;
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use rustc_lint::LateContext;
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use rustc_middle::ty::{self, Ty};
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use super::UNINIT_ASSUMED_INIT;
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@ -13,7 +12,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr
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if let hir::ExprKind::Call(callee, args) = recv.kind;
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if args.is_empty();
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if is_expr_path_def_path(cx, callee, &paths::MEM_MAYBEUNINIT_UNINIT);
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if !is_maybe_uninit_ty_valid(cx, cx.typeck_results().expr_ty_adjusted(expr));
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if !is_uninit_value_valid_for_ty(cx, cx.typeck_results().expr_ty_adjusted(expr));
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then {
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span_lint(
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cx,
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@ -24,12 +23,3 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr
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}
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}
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}
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fn is_maybe_uninit_ty_valid(cx: &LateContext<'_>, ty: Ty<'_>) -> bool {
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match ty.kind() {
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ty::Array(component, _) => is_maybe_uninit_ty_valid(cx, component),
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ty::Tuple(types) => types.types().all(|ty| is_maybe_uninit_ty_valid(cx, ty)),
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ty::Adt(adt, _) => match_def_path(cx, adt.did, &paths::MEM_MAYBEUNINIT),
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_ => false,
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}
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}
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223
clippy_lints/src/uninit_vec.rs
Normal file
223
clippy_lints/src/uninit_vec.rs
Normal file
@ -0,0 +1,223 @@
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use clippy_utils::diagnostics::{span_lint, span_lint_and_then};
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use clippy_utils::higher::{get_vec_init_kind, VecInitKind};
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use clippy_utils::ty::{is_type_diagnostic_item, is_uninit_value_valid_for_ty};
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use clippy_utils::{is_lint_allowed, path_to_local_id, peel_hir_expr_while, SpanlessEq};
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use rustc_hir::{Block, Expr, ExprKind, HirId, PatKind, PathSegment, Stmt, StmtKind};
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_middle::lint::in_external_macro;
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use rustc_middle::ty;
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use rustc_session::{declare_lint_pass, declare_tool_lint};
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use rustc_span::{sym, Span};
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// TODO: add `ReadBuf` (RFC 2930) in "How to fix" once it is available in std
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declare_clippy_lint! {
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/// ### What it does
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/// Checks for `set_len()` call that creates `Vec` with uninitialized elements.
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/// This is commonly caused by calling `set_len()` right after allocating or
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/// reserving a buffer with `new()`, `default()`, `with_capacity()`, or `reserve()`.
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///
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/// ### Why is this bad?
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/// It creates a `Vec` with uninitialized data, which leads to
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/// undefined behavior with most safe operations. Notably, uninitialized
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/// `Vec<u8>` must not be used with generic `Read`.
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///
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/// Moreover, calling `set_len()` on a `Vec` created with `new()` or `default()`
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/// creates out-of-bound values that lead to heap memory corruption when used.
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///
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/// ### Known Problems
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/// This lint only checks directly adjacent statements.
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///
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/// ### Example
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/// ```rust,ignore
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/// let mut vec: Vec<u8> = Vec::with_capacity(1000);
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/// unsafe { vec.set_len(1000); }
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/// reader.read(&mut vec); // undefined behavior!
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/// ```
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///
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/// ### How to fix?
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/// 1. Use an initialized buffer:
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/// ```rust,ignore
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/// let mut vec: Vec<u8> = vec![0; 1000];
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/// reader.read(&mut vec);
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/// ```
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/// 2. Wrap the content in `MaybeUninit`:
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/// ```rust,ignore
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/// let mut vec: Vec<MaybeUninit<T>> = Vec::with_capacity(1000);
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/// vec.set_len(1000); // `MaybeUninit` can be uninitialized
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/// ```
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/// 3. If you are on nightly, `Vec::spare_capacity_mut()` is available:
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/// ```rust,ignore
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/// let mut vec: Vec<u8> = Vec::with_capacity(1000);
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/// let remaining = vec.spare_capacity_mut(); // `&mut [MaybeUninit<u8>]`
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/// // perform initialization with `remaining`
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/// vec.set_len(...); // Safe to call `set_len()` on initialized part
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/// ```
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pub UNINIT_VEC,
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correctness,
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"Vec with uninitialized data"
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}
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declare_lint_pass!(UninitVec => [UNINIT_VEC]);
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// FIXME: update to a visitor-based implementation.
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// Threads: https://github.com/rust-lang/rust-clippy/pull/7682#discussion_r710998368
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impl<'tcx> LateLintPass<'tcx> for UninitVec {
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fn check_block(&mut self, cx: &LateContext<'tcx>, block: &'tcx Block<'_>) {
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if !in_external_macro(cx.tcx.sess, block.span) {
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for w in block.stmts.windows(2) {
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if let StmtKind::Expr(expr) | StmtKind::Semi(expr) = w[1].kind {
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handle_uninit_vec_pair(cx, &w[0], expr);
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}
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}
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if let (Some(stmt), Some(expr)) = (block.stmts.last(), block.expr) {
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handle_uninit_vec_pair(cx, stmt, expr);
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}
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}
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}
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}
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fn handle_uninit_vec_pair(
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cx: &LateContext<'tcx>,
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maybe_init_or_reserve: &'tcx Stmt<'tcx>,
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maybe_set_len: &'tcx Expr<'tcx>,
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) {
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if_chain! {
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if let Some(vec) = extract_init_or_reserve_target(cx, maybe_init_or_reserve);
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if let Some((set_len_self, call_span)) = extract_set_len_self(cx, maybe_set_len);
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if vec.location.eq_expr(cx, set_len_self);
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if let ty::Ref(_, vec_ty, _) = cx.typeck_results().expr_ty_adjusted(set_len_self).kind();
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if let ty::Adt(_, substs) = vec_ty.kind();
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// `#[allow(...)]` attribute can be set on enclosing unsafe block of `set_len()`
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if !is_lint_allowed(cx, UNINIT_VEC, maybe_set_len.hir_id);
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then {
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if vec.has_capacity() {
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// with_capacity / reserve -> set_len
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// Check T of Vec<T>
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if !is_uninit_value_valid_for_ty(cx, substs.type_at(0)) {
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// FIXME: #7698, false positive of the internal lints
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#[allow(clippy::collapsible_span_lint_calls)]
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span_lint_and_then(
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cx,
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UNINIT_VEC,
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vec![call_span, maybe_init_or_reserve.span],
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"calling `set_len()` immediately after reserving a buffer creates uninitialized values",
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|diag| {
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diag.help("initialize the buffer or wrap the content in `MaybeUninit`");
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},
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);
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}
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} else {
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// new / default -> set_len
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span_lint(
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cx,
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UNINIT_VEC,
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vec![call_span, maybe_init_or_reserve.span],
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"calling `set_len()` on empty `Vec` creates out-of-bound values",
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);
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}
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}
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}
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}
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/// The target `Vec` that is initialized or reserved
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#[derive(Clone, Copy)]
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struct TargetVec<'tcx> {
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location: VecLocation<'tcx>,
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/// `None` if `reserve()`
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init_kind: Option<VecInitKind>,
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}
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impl TargetVec<'_> {
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pub fn has_capacity(self) -> bool {
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!matches!(self.init_kind, Some(VecInitKind::New | VecInitKind::Default))
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}
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}
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#[derive(Clone, Copy)]
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enum VecLocation<'tcx> {
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Local(HirId),
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Expr(&'tcx Expr<'tcx>),
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}
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impl<'tcx> VecLocation<'tcx> {
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pub fn eq_expr(self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> bool {
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match self {
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VecLocation::Local(hir_id) => path_to_local_id(expr, hir_id),
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VecLocation::Expr(self_expr) => SpanlessEq::new(cx).eq_expr(self_expr, expr),
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}
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}
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}
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/// Finds the target location where the result of `Vec` initialization is stored
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/// or `self` expression for `Vec::reserve()`.
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fn extract_init_or_reserve_target<'tcx>(cx: &LateContext<'tcx>, stmt: &'tcx Stmt<'tcx>) -> Option<TargetVec<'tcx>> {
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match stmt.kind {
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StmtKind::Local(local) => {
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if_chain! {
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if let Some(init_expr) = local.init;
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if let PatKind::Binding(_, hir_id, _, None) = local.pat.kind;
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if let Some(init_kind) = get_vec_init_kind(cx, init_expr);
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then {
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return Some(TargetVec {
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location: VecLocation::Local(hir_id),
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init_kind: Some(init_kind),
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})
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}
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}
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},
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StmtKind::Expr(expr) | StmtKind::Semi(expr) => match expr.kind {
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ExprKind::Assign(lhs, rhs, _span) => {
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if let Some(init_kind) = get_vec_init_kind(cx, rhs) {
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return Some(TargetVec {
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location: VecLocation::Expr(lhs),
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init_kind: Some(init_kind),
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});
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}
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},
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ExprKind::MethodCall(path, _, [self_expr, _], _) if is_reserve(cx, path, self_expr) => {
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return Some(TargetVec {
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location: VecLocation::Expr(self_expr),
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init_kind: None,
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});
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},
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_ => (),
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},
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StmtKind::Item(_) => (),
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}
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None
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}
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fn is_reserve(cx: &LateContext<'_>, path: &PathSegment<'_>, self_expr: &Expr<'_>) -> bool {
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is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(self_expr).peel_refs(), sym::Vec)
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&& path.ident.name.as_str() == "reserve"
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}
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/// Returns self if the expression is `Vec::set_len()`
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fn extract_set_len_self(cx: &LateContext<'_>, expr: &'tcx Expr<'_>) -> Option<(&'tcx Expr<'tcx>, Span)> {
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// peel unsafe blocks in `unsafe { vec.set_len() }`
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let expr = peel_hir_expr_while(expr, |e| {
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if let ExprKind::Block(block, _) = e.kind {
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// Extract the first statement/expression
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match (block.stmts.get(0).map(|stmt| &stmt.kind), block.expr) {
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(None, Some(expr)) => Some(expr),
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(Some(StmtKind::Expr(expr) | StmtKind::Semi(expr)), _) => Some(expr),
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_ => None,
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}
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} else {
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None
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}
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});
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match expr.kind {
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ExprKind::MethodCall(path, _, [self_expr, _], _) => {
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let self_type = cx.typeck_results().expr_ty(self_expr).peel_refs();
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if is_type_diagnostic_item(cx, self_type, sym::Vec) && path.ident.name.as_str() == "set_len" {
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Some((self_expr, expr.span))
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} else {
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None
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}
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},
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_ => None,
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}
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}
|
@ -1,16 +1,14 @@
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use clippy_utils::diagnostics::span_lint_and_sugg;
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use clippy_utils::higher::{get_vec_init_kind, VecInitKind};
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use clippy_utils::source::snippet;
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use clippy_utils::ty::is_type_diagnostic_item;
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use clippy_utils::{match_def_path, path_to_local, path_to_local_id, paths};
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use clippy_utils::{path_to_local, path_to_local_id};
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use if_chain::if_chain;
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use rustc_ast::ast::LitKind;
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use rustc_errors::Applicability;
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use rustc_hir::{BindingAnnotation, Block, Expr, ExprKind, HirId, Local, PatKind, QPath, Stmt, StmtKind};
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use rustc_hir::{BindingAnnotation, Block, Expr, ExprKind, HirId, Local, PatKind, Stmt, StmtKind};
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use rustc_lint::{LateContext, LateLintPass, LintContext};
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use rustc_middle::lint::in_external_macro;
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use rustc_session::{declare_tool_lint, impl_lint_pass};
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use rustc_span::{symbol::sym, Span};
|
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use std::convert::TryInto;
|
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use rustc_span::Span;
|
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|
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declare_clippy_lint! {
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/// ### What it does
|
||||
@ -41,11 +39,6 @@ pub struct VecInitThenPush {
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searcher: Option<VecPushSearcher>,
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}
|
||||
|
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#[derive(Clone, Copy)]
|
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enum VecInitKind {
|
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New,
|
||||
WithCapacity(u64),
|
||||
}
|
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struct VecPushSearcher {
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local_id: HirId,
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init: VecInitKind,
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@ -58,7 +51,8 @@ impl VecPushSearcher {
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||||
fn display_err(&self, cx: &LateContext<'_>) {
|
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match self.init {
|
||||
_ if self.found == 0 => return,
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||||
VecInitKind::WithCapacity(x) if x > self.found => return,
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VecInitKind::WithLiteralCapacity(x) if x > self.found => return,
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VecInitKind::WithExprCapacity(_) => return,
|
||||
_ => (),
|
||||
};
|
||||
|
||||
@ -152,37 +146,3 @@ fn check_block_post(&mut self, cx: &LateContext<'tcx>, _: &'tcx Block<'tcx>) {
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn get_vec_init_kind<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Option<VecInitKind> {
|
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if let ExprKind::Call(func, args) = expr.kind {
|
||||
match func.kind {
|
||||
ExprKind::Path(QPath::TypeRelative(ty, name))
|
||||
if is_type_diagnostic_item(cx, cx.typeck_results().node_type(ty.hir_id), sym::Vec) =>
|
||||
{
|
||||
if name.ident.name == sym::new {
|
||||
return Some(VecInitKind::New);
|
||||
} else if name.ident.name.as_str() == "with_capacity" {
|
||||
return args.get(0).and_then(|arg| {
|
||||
if_chain! {
|
||||
if let ExprKind::Lit(lit) = &arg.kind;
|
||||
if let LitKind::Int(num, _) = lit.node;
|
||||
then {
|
||||
Some(VecInitKind::WithCapacity(num.try_into().ok()?))
|
||||
} else {
|
||||
None
|
||||
}
|
||||
}
|
||||
});
|
||||
}
|
||||
}
|
||||
ExprKind::Path(QPath::Resolved(_, path))
|
||||
if match_def_path(cx, path.res.opt_def_id()?, &paths::DEFAULT_TRAIT_METHOD)
|
||||
&& is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(expr), sym::Vec) =>
|
||||
{
|
||||
return Some(VecInitKind::New);
|
||||
}
|
||||
_ => (),
|
||||
}
|
||||
}
|
||||
None
|
||||
}
|
||||
|
@ -2,13 +2,16 @@
|
||||
|
||||
#![deny(clippy::missing_docs_in_private_items)]
|
||||
|
||||
use crate::ty::is_type_diagnostic_item;
|
||||
use crate::{is_expn_of, match_def_path, paths};
|
||||
use if_chain::if_chain;
|
||||
use rustc_ast::ast::{self, LitKind};
|
||||
use rustc_hir as hir;
|
||||
use rustc_hir::{Arm, Block, BorrowKind, Expr, ExprKind, LoopSource, MatchSource, Node, Pat, StmtKind, UnOp};
|
||||
use rustc_hir::{
|
||||
Arm, Block, BorrowKind, Expr, ExprKind, HirId, LoopSource, MatchSource, Node, Pat, QPath, StmtKind, UnOp,
|
||||
};
|
||||
use rustc_lint::LateContext;
|
||||
use rustc_span::{sym, ExpnKind, Span, Symbol};
|
||||
use rustc_span::{sym, symbol, ExpnKind, Span, Symbol};
|
||||
|
||||
/// The essential nodes of a desugared for loop as well as the entire span:
|
||||
/// `for pat in arg { body }` becomes `(pat, arg, body)`. Return `(pat, arg, body, span)`.
|
||||
@ -632,3 +635,51 @@ pub fn parse(expr: &'tcx Expr<'tcx>) -> Option<Self> {
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/// A parsed `Vec` initialization expression
|
||||
#[derive(Clone, Copy)]
|
||||
pub enum VecInitKind {
|
||||
/// `Vec::new()`
|
||||
New,
|
||||
/// `Vec::default()` or `Default::default()`
|
||||
Default,
|
||||
/// `Vec::with_capacity(123)`
|
||||
WithLiteralCapacity(u64),
|
||||
/// `Vec::with_capacity(slice.len())`
|
||||
WithExprCapacity(HirId),
|
||||
}
|
||||
|
||||
/// Checks if given expression is an initialization of `Vec` and returns its kind.
|
||||
pub fn get_vec_init_kind<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Option<VecInitKind> {
|
||||
if let ExprKind::Call(func, args) = expr.kind {
|
||||
match func.kind {
|
||||
ExprKind::Path(QPath::TypeRelative(ty, name))
|
||||
if is_type_diagnostic_item(cx, cx.typeck_results().node_type(ty.hir_id), sym::Vec) =>
|
||||
{
|
||||
if name.ident.name == sym::new {
|
||||
return Some(VecInitKind::New);
|
||||
} else if name.ident.name == symbol::kw::Default {
|
||||
return Some(VecInitKind::Default);
|
||||
} else if name.ident.name.as_str() == "with_capacity" {
|
||||
let arg = args.get(0)?;
|
||||
if_chain! {
|
||||
if let ExprKind::Lit(lit) = &arg.kind;
|
||||
if let LitKind::Int(num, _) = lit.node;
|
||||
then {
|
||||
return Some(VecInitKind::WithLiteralCapacity(num.try_into().ok()?))
|
||||
}
|
||||
}
|
||||
return Some(VecInitKind::WithExprCapacity(arg.hir_id));
|
||||
}
|
||||
}
|
||||
ExprKind::Path(QPath::Resolved(_, path))
|
||||
if match_def_path(cx, path.res.opt_def_id()?, &paths::DEFAULT_TRAIT_METHOD)
|
||||
&& is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(expr), sym::Vec) =>
|
||||
{
|
||||
return Some(VecInitKind::Default);
|
||||
}
|
||||
_ => (),
|
||||
}
|
||||
}
|
||||
None
|
||||
}
|
||||
|
@ -367,3 +367,13 @@ pub fn same_type_and_consts(a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
|
||||
_ => a == b,
|
||||
}
|
||||
}
|
||||
|
||||
/// Checks if a given type looks safe to be uninitialized.
|
||||
pub fn is_uninit_value_valid_for_ty(cx: &LateContext<'_>, ty: Ty<'_>) -> bool {
|
||||
match ty.kind() {
|
||||
ty::Array(component, _) => is_uninit_value_valid_for_ty(cx, component),
|
||||
ty::Tuple(types) => types.types().all(|ty| is_uninit_value_valid_for_ty(cx, ty)),
|
||||
ty::Adt(adt, _) => cx.tcx.lang_items().maybe_uninit() == Some(adt.did),
|
||||
_ => false,
|
||||
}
|
||||
}
|
||||
|
94
tests/ui/uninit_vec.rs
Normal file
94
tests/ui/uninit_vec.rs
Normal file
@ -0,0 +1,94 @@
|
||||
#![warn(clippy::uninit_vec)]
|
||||
|
||||
use std::mem::MaybeUninit;
|
||||
|
||||
#[derive(Default)]
|
||||
struct MyVec {
|
||||
vec: Vec<u8>,
|
||||
}
|
||||
|
||||
fn main() {
|
||||
// with_capacity() -> set_len() should be detected
|
||||
let mut vec: Vec<u8> = Vec::with_capacity(1000);
|
||||
unsafe {
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
// reserve() -> set_len() should be detected
|
||||
vec.reserve(1000);
|
||||
unsafe {
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
// new() -> set_len() should be detected
|
||||
let mut vec: Vec<u8> = Vec::new();
|
||||
unsafe {
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
// default() -> set_len() should be detected
|
||||
let mut vec: Vec<u8> = Default::default();
|
||||
unsafe {
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
let mut vec: Vec<u8> = Vec::default();
|
||||
unsafe {
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
// test when both calls are enclosed in the same unsafe block
|
||||
unsafe {
|
||||
let mut vec: Vec<u8> = Vec::with_capacity(1000);
|
||||
vec.set_len(200);
|
||||
|
||||
vec.reserve(1000);
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
let mut vec: Vec<u8> = Vec::with_capacity(1000);
|
||||
unsafe {
|
||||
// test the case where there are other statements in the following unsafe block
|
||||
vec.set_len(200);
|
||||
assert!(vec.len() == 200);
|
||||
}
|
||||
|
||||
// handle vec stored in the field of a struct
|
||||
let mut my_vec = MyVec::default();
|
||||
my_vec.vec.reserve(1000);
|
||||
unsafe {
|
||||
my_vec.vec.set_len(200);
|
||||
}
|
||||
|
||||
my_vec.vec = Vec::with_capacity(1000);
|
||||
unsafe {
|
||||
my_vec.vec.set_len(200);
|
||||
}
|
||||
|
||||
// Test `#[allow(...)]` attributes on inner unsafe block (shouldn't trigger)
|
||||
let mut vec: Vec<u8> = Vec::with_capacity(1000);
|
||||
#[allow(clippy::uninit_vec)]
|
||||
unsafe {
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
// MaybeUninit-wrapped types should not be detected
|
||||
unsafe {
|
||||
let mut vec: Vec<MaybeUninit<u8>> = Vec::with_capacity(1000);
|
||||
vec.set_len(200);
|
||||
|
||||
let mut vec: Vec<(MaybeUninit<u8>, MaybeUninit<bool>)> = Vec::with_capacity(1000);
|
||||
vec.set_len(200);
|
||||
|
||||
let mut vec: Vec<(MaybeUninit<u8>, [MaybeUninit<bool>; 2])> = Vec::with_capacity(1000);
|
||||
vec.set_len(200);
|
||||
}
|
||||
|
||||
// known false negative
|
||||
let mut vec1: Vec<u8> = Vec::with_capacity(1000);
|
||||
let mut vec2: Vec<u8> = Vec::with_capacity(1000);
|
||||
unsafe {
|
||||
vec1.set_len(200);
|
||||
vec2.set_len(200);
|
||||
}
|
||||
}
|
105
tests/ui/uninit_vec.stderr
Normal file
105
tests/ui/uninit_vec.stderr
Normal file
@ -0,0 +1,105 @@
|
||||
error: calling `set_len()` immediately after reserving a buffer creates uninitialized values
|
||||
--> $DIR/uninit_vec.rs:12:5
|
||||
|
|
||||
LL | let mut vec: Vec<u8> = Vec::with_capacity(1000);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
LL | unsafe {
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
|
||||
= note: `-D clippy::uninit-vec` implied by `-D warnings`
|
||||
= help: initialize the buffer or wrap the content in `MaybeUninit`
|
||||
|
||||
error: calling `set_len()` immediately after reserving a buffer creates uninitialized values
|
||||
--> $DIR/uninit_vec.rs:18:5
|
||||
|
|
||||
LL | vec.reserve(1000);
|
||||
| ^^^^^^^^^^^^^^^^^^
|
||||
LL | unsafe {
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
|
||||
= help: initialize the buffer or wrap the content in `MaybeUninit`
|
||||
|
||||
error: calling `set_len()` on empty `Vec` creates out-of-bound values
|
||||
--> $DIR/uninit_vec.rs:24:5
|
||||
|
|
||||
LL | let mut vec: Vec<u8> = Vec::new();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
LL | unsafe {
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
||||
error: calling `set_len()` on empty `Vec` creates out-of-bound values
|
||||
--> $DIR/uninit_vec.rs:30:5
|
||||
|
|
||||
LL | let mut vec: Vec<u8> = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
LL | unsafe {
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
||||
error: calling `set_len()` on empty `Vec` creates out-of-bound values
|
||||
--> $DIR/uninit_vec.rs:35:5
|
||||
|
|
||||
LL | let mut vec: Vec<u8> = Vec::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
LL | unsafe {
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
||||
error: calling `set_len()` immediately after reserving a buffer creates uninitialized values
|
||||
--> $DIR/uninit_vec.rs:49:5
|
||||
|
|
||||
LL | let mut vec: Vec<u8> = Vec::with_capacity(1000);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
...
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
|
||||
= help: initialize the buffer or wrap the content in `MaybeUninit`
|
||||
|
||||
error: calling `set_len()` immediately after reserving a buffer creates uninitialized values
|
||||
--> $DIR/uninit_vec.rs:58:5
|
||||
|
|
||||
LL | my_vec.vec.reserve(1000);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
LL | unsafe {
|
||||
LL | my_vec.vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
|
||||
= help: initialize the buffer or wrap the content in `MaybeUninit`
|
||||
|
||||
error: calling `set_len()` immediately after reserving a buffer creates uninitialized values
|
||||
--> $DIR/uninit_vec.rs:63:5
|
||||
|
|
||||
LL | my_vec.vec = Vec::with_capacity(1000);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
LL | unsafe {
|
||||
LL | my_vec.vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
|
||||
= help: initialize the buffer or wrap the content in `MaybeUninit`
|
||||
|
||||
error: calling `set_len()` immediately after reserving a buffer creates uninitialized values
|
||||
--> $DIR/uninit_vec.rs:42:9
|
||||
|
|
||||
LL | let mut vec: Vec<u8> = Vec::with_capacity(1000);
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
|
||||
= help: initialize the buffer or wrap the content in `MaybeUninit`
|
||||
|
||||
error: calling `set_len()` immediately after reserving a buffer creates uninitialized values
|
||||
--> $DIR/uninit_vec.rs:45:9
|
||||
|
|
||||
LL | vec.reserve(1000);
|
||||
| ^^^^^^^^^^^^^^^^^^
|
||||
LL | vec.set_len(200);
|
||||
| ^^^^^^^^^^^^^^^^
|
||||
|
|
||||
= help: initialize the buffer or wrap the content in `MaybeUninit`
|
||||
|
||||
error: aborting due to 10 previous errors
|
||||
|
Loading…
Reference in New Issue
Block a user