From 5363f350887b1e5b5dd21a86f88c8af9d7fea6da Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:18:25 +0200 Subject: Merging upstream version 1.67.1+dfsg1. Signed-off-by: Daniel Baumann --- compiler/rustc_lint/src/builtin.rs | 288 +++++++++++++++++++++++++------------ 1 file changed, 198 insertions(+), 90 deletions(-) (limited to 'compiler/rustc_lint/src/builtin.rs') diff --git a/compiler/rustc_lint/src/builtin.rs b/compiler/rustc_lint/src/builtin.rs index d425adf47..c6c7caa7c 100644 --- a/compiler/rustc_lint/src/builtin.rs +++ b/compiler/rustc_lint/src/builtin.rs @@ -25,6 +25,7 @@ use crate::{ types::{transparent_newtype_field, CItemKind}, EarlyContext, EarlyLintPass, LateContext, LateLintPass, LintContext, }; +use hir::IsAsync; use rustc_ast::attr; use rustc_ast::tokenstream::{TokenStream, TokenTree}; use rustc_ast::visit::{FnCtxt, FnKind}; @@ -40,7 +41,10 @@ use rustc_feature::{deprecated_attributes, AttributeGate, BuiltinAttribute, Gate use rustc_hir as hir; use rustc_hir::def::{DefKind, Res}; use rustc_hir::def_id::{DefId, LocalDefId, LocalDefIdSet, CRATE_DEF_ID}; -use rustc_hir::{ForeignItemKind, GenericParamKind, HirId, PatKind, PredicateOrigin}; +use rustc_hir::intravisit::FnKind as HirFnKind; +use rustc_hir::{ + Body, FnDecl, ForeignItemKind, GenericParamKind, HirId, Node, PatKind, PredicateOrigin, +}; use rustc_index::vec::Idx; use rustc_middle::lint::in_external_macro; use rustc_middle::ty::layout::{LayoutError, LayoutOf}; @@ -52,7 +56,7 @@ use rustc_span::edition::Edition; use rustc_span::source_map::Spanned; use rustc_span::symbol::{kw, sym, Ident, Symbol}; use rustc_span::{BytePos, InnerSpan, Span}; -use rustc_target::abi::VariantIdx; +use rustc_target::abi::{Abi, VariantIdx}; use rustc_trait_selection::traits::{self, misc::can_type_implement_copy}; use crate::nonstandard_style::{method_context, MethodLateContext}; @@ -98,9 +102,10 @@ fn pierce_parens(mut expr: &ast::Expr) -> &ast::Expr { impl EarlyLintPass for WhileTrue { fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &ast::Expr) { if let ast::ExprKind::While(cond, _, label) = &e.kind - && let ast::ExprKind::Lit(ref lit) = pierce_parens(cond).kind - && let ast::LitKind::Bool(true) = lit.kind - && !lit.span.from_expansion() + && let cond = pierce_parens(cond) + && let ast::ExprKind::Lit(token_lit) = cond.kind + && let token::Lit { kind: token::Bool, symbol: kw::True, .. } = token_lit + && !cond.span.from_expansion() { let condition_span = e.span.with_hi(cond.span.hi()); cx.struct_span_lint( @@ -185,9 +190,8 @@ impl<'tcx> LateLintPass<'tcx> for BoxPointers { // If it's a struct, we also have to check the fields' types match it.kind { hir::ItemKind::Struct(ref struct_def, _) | hir::ItemKind::Union(ref struct_def, _) => { - for struct_field in struct_def.fields() { - let def_id = cx.tcx.hir().local_def_id(struct_field.hir_id); - self.check_heap_type(cx, struct_field.span, cx.tcx.type_of(def_id)); + for field in struct_def.fields() { + self.check_heap_type(cx, field.span, cx.tcx.type_of(field.def_id)); } } _ => (), @@ -259,7 +263,7 @@ impl<'tcx> LateLintPass<'tcx> for NonShorthandFieldPatterns { } if let PatKind::Binding(binding_annot, _, ident, None) = fieldpat.pat.kind { if cx.tcx.find_field_index(ident, &variant) - == Some(cx.tcx.field_index(fieldpat.hir_id, cx.typeck_results())) + == Some(cx.typeck_results().field_index(fieldpat.hir_id)) { cx.struct_span_lint( NON_SHORTHAND_FIELD_PATTERNS, @@ -673,13 +677,12 @@ impl<'tcx> LateLintPass<'tcx> for MissingDoc { fn check_field_def(&mut self, cx: &LateContext<'_>, sf: &hir::FieldDef<'_>) { if !sf.is_positional() { - let def_id = cx.tcx.hir().local_def_id(sf.hir_id); - self.check_missing_docs_attrs(cx, def_id, "a", "struct field") + self.check_missing_docs_attrs(cx, sf.def_id, "a", "struct field") } } fn check_variant(&mut self, cx: &LateContext<'_>, v: &hir::Variant<'_>) { - self.check_missing_docs_attrs(cx, cx.tcx.hir().local_def_id(v.id), "a", "variant"); + self.check_missing_docs_attrs(cx, v.def_id, "a", "variant"); } } @@ -1269,10 +1272,10 @@ declare_lint_pass!(MutableTransmutes => [MUTABLE_TRANSMUTES]); impl<'tcx> LateLintPass<'tcx> for MutableTransmutes { fn check_expr(&mut self, cx: &LateContext<'_>, expr: &hir::Expr<'_>) { - if let Some((&ty::Ref(_, _, from_mt), &ty::Ref(_, _, to_mt))) = + if let Some((&ty::Ref(_, _, from_mutbl), &ty::Ref(_, _, to_mutbl))) = get_transmute_from_to(cx, expr).map(|(ty1, ty2)| (ty1.kind(), ty2.kind())) { - if to_mt == hir::Mutability::Mut && from_mt == hir::Mutability::Not { + if from_mutbl < to_mutbl { cx.struct_span_lint( MUTABLE_TRANSMUTES, expr.span, @@ -1338,6 +1341,72 @@ impl<'tcx> LateLintPass<'tcx> for UnstableFeatures { } } +declare_lint! { + /// The `ungated_async_fn_track_caller` lint warns when the + /// `#[track_caller]` attribute is used on an async function, method, or + /// closure, without enabling the corresponding unstable feature flag. + /// + /// ### Example + /// + /// ```rust + /// #[track_caller] + /// async fn foo() {} + /// ``` + /// + /// {{produces}} + /// + /// ### Explanation + /// + /// The attribute must be used in conjunction with the + /// [`closure_track_caller` feature flag]. Otherwise, the `#[track_caller]` + /// annotation will function as as no-op. + /// + /// [`closure_track_caller` feature flag]: https://doc.rust-lang.org/beta/unstable-book/language-features/closure-track-caller.html + UNGATED_ASYNC_FN_TRACK_CALLER, + Warn, + "enabling track_caller on an async fn is a no-op unless the closure_track_caller feature is enabled" +} + +declare_lint_pass!( + /// Explains corresponding feature flag must be enabled for the `#[track_caller] attribute to + /// do anything + UngatedAsyncFnTrackCaller => [UNGATED_ASYNC_FN_TRACK_CALLER] +); + +impl<'tcx> LateLintPass<'tcx> for UngatedAsyncFnTrackCaller { + fn check_fn( + &mut self, + cx: &LateContext<'_>, + fn_kind: HirFnKind<'_>, + _: &'tcx FnDecl<'_>, + _: &'tcx Body<'_>, + span: Span, + hir_id: HirId, + ) { + if fn_kind.asyncness() == IsAsync::Async + && !cx.tcx.features().closure_track_caller + && let attrs = cx.tcx.hir().attrs(hir_id) + // Now, check if the function has the `#[track_caller]` attribute + && let Some(attr) = attrs.iter().find(|attr| attr.has_name(sym::track_caller)) + { + cx.struct_span_lint( + UNGATED_ASYNC_FN_TRACK_CALLER, + attr.span, + fluent::lint_ungated_async_fn_track_caller, + |lint| { + lint.span_label(span, fluent::label); + rustc_session::parse::add_feature_diagnostics( + lint, + &cx.tcx.sess.parse_sess, + sym::closure_track_caller, + ); + lint + }, + ); + } + } +} + declare_lint! { /// The `unreachable_pub` lint triggers for `pub` items not reachable from /// the crate root. @@ -1423,8 +1492,11 @@ impl<'tcx> LateLintPass<'tcx> for UnreachablePub { } fn check_field_def(&mut self, cx: &LateContext<'_>, field: &hir::FieldDef<'_>) { - let def_id = cx.tcx.hir().local_def_id(field.hir_id); - self.perform_lint(cx, "field", def_id, field.vis_span, false); + let map = cx.tcx.hir(); + if matches!(map.get(map.get_parent_node(field.hir_id)), Node::Variant(_)) { + return; + } + self.perform_lint(cx, "field", field.def_id, field.vis_span, false); } fn check_impl_item(&mut self, cx: &LateContext<'_>, impl_item: &hir::ImplItem<'_>) { @@ -1636,19 +1708,20 @@ declare_lint_pass!( impl<'tcx> LateLintPass<'tcx> for TrivialConstraints { fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx hir::Item<'tcx>) { use rustc_middle::ty::visit::TypeVisitable; + use rustc_middle::ty::Clause; use rustc_middle::ty::PredicateKind::*; if cx.tcx.features().trivial_bounds { let predicates = cx.tcx.predicates_of(item.owner_id); for &(predicate, span) in predicates.predicates { let predicate_kind_name = match predicate.kind().skip_binder() { - Trait(..) => "trait", - TypeOutlives(..) | - RegionOutlives(..) => "lifetime", + Clause(Clause::Trait(..)) => "trait", + Clause(Clause::TypeOutlives(..)) | + Clause(Clause::RegionOutlives(..)) => "lifetime", // Ignore projections, as they can only be global // if the trait bound is global - Projection(..) | + Clause(Clause::Projection(..)) | // Ignore bounds that a user can't type WellFormed(..) | ObjectSafe(..) | @@ -1657,6 +1730,7 @@ impl<'tcx> LateLintPass<'tcx> for TrivialConstraints { Coerce(..) | ConstEvaluatable(..) | ConstEquate(..) | + Ambiguous | TypeWellFormedFromEnv(..) => continue, }; if predicate.is_global() { @@ -2028,10 +2102,10 @@ impl KeywordIdents { impl EarlyLintPass for KeywordIdents { fn check_mac_def(&mut self, cx: &EarlyContext<'_>, mac_def: &ast::MacroDef) { - self.check_tokens(cx, mac_def.body.inner_tokens()); + self.check_tokens(cx, mac_def.body.tokens.clone()); } fn check_mac(&mut self, cx: &EarlyContext<'_>, mac: &ast::MacCall) { - self.check_tokens(cx, mac.args.inner_tokens()); + self.check_tokens(cx, mac.args.tokens.clone()); } fn check_ident(&mut self, cx: &EarlyContext<'_>, ident: Ident) { self.check_ident_token(cx, UnderMacro(false), ident); @@ -2042,13 +2116,13 @@ declare_lint_pass!(ExplicitOutlivesRequirements => [EXPLICIT_OUTLIVES_REQUIREMEN impl ExplicitOutlivesRequirements { fn lifetimes_outliving_lifetime<'tcx>( - inferred_outlives: &'tcx [(ty::Predicate<'tcx>, Span)], + inferred_outlives: &'tcx [(ty::Clause<'tcx>, Span)], def_id: DefId, ) -> Vec> { inferred_outlives .iter() - .filter_map(|(pred, _)| match pred.kind().skip_binder() { - ty::PredicateKind::RegionOutlives(ty::OutlivesPredicate(a, b)) => match *a { + .filter_map(|(clause, _)| match *clause { + ty::Clause::RegionOutlives(ty::OutlivesPredicate(a, b)) => match *a { ty::ReEarlyBound(ebr) if ebr.def_id == def_id => Some(b), _ => None, }, @@ -2058,13 +2132,13 @@ impl ExplicitOutlivesRequirements { } fn lifetimes_outliving_type<'tcx>( - inferred_outlives: &'tcx [(ty::Predicate<'tcx>, Span)], + inferred_outlives: &'tcx [(ty::Clause<'tcx>, Span)], index: u32, ) -> Vec> { inferred_outlives .iter() - .filter_map(|(pred, _)| match pred.kind().skip_binder() { - ty::PredicateKind::TypeOutlives(ty::OutlivesPredicate(a, b)) => { + .filter_map(|(clause, _)| match *clause { + ty::Clause::TypeOutlives(ty::OutlivesPredicate(a, b)) => { a.is_param(index).then_some(b) } _ => None, @@ -2405,8 +2479,34 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { } /// Information about why a type cannot be initialized this way. - /// Contains an error message and optionally a span to point at. - type InitError = (String, Option); + struct InitError { + message: String, + /// Spans from struct fields and similar that can be obtained from just the type. + span: Option, + /// Used to report a trace through adts. + nested: Option>, + } + impl InitError { + fn spanned(self, span: Span) -> InitError { + Self { span: Some(span), ..self } + } + + fn nested(self, nested: impl Into>) -> InitError { + assert!(self.nested.is_none()); + Self { nested: nested.into().map(Box::new), ..self } + } + } + + impl<'a> From<&'a str> for InitError { + fn from(s: &'a str) -> Self { + s.to_owned().into() + } + } + impl From for InitError { + fn from(message: String) -> Self { + Self { message, span: None, nested: None } + } + } /// Test if this constant is all-0. fn is_zero(expr: &hir::Expr<'_>) -> bool { @@ -2462,25 +2562,54 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { fn variant_find_init_error<'tcx>( cx: &LateContext<'tcx>, + ty: Ty<'tcx>, variant: &VariantDef, substs: ty::SubstsRef<'tcx>, descr: &str, init: InitKind, ) -> Option { - variant.fields.iter().find_map(|field| { - ty_find_init_error(cx, field.ty(cx.tcx, substs), init).map(|(mut msg, span)| { - if span.is_none() { - // Point to this field, should be helpful for figuring - // out where the source of the error is. - let span = cx.tcx.def_span(field.did); - write!(&mut msg, " (in this {descr})").unwrap(); - (msg, Some(span)) + let mut field_err = variant.fields.iter().find_map(|field| { + ty_find_init_error(cx, field.ty(cx.tcx, substs), init).map(|mut err| { + if !field.did.is_local() { + err + } else if err.span.is_none() { + err.span = Some(cx.tcx.def_span(field.did)); + write!(&mut err.message, " (in this {descr})").unwrap(); + err } else { - // Just forward. - (msg, span) + InitError::from(format!("in this {descr}")) + .spanned(cx.tcx.def_span(field.did)) + .nested(err) } }) - }) + }); + + // Check if this ADT has a constrained layout (like `NonNull` and friends). + if let Ok(layout) = cx.tcx.layout_of(cx.param_env.and(ty)) { + if let Abi::Scalar(scalar) | Abi::ScalarPair(scalar, _) = &layout.abi { + let range = scalar.valid_range(cx); + let msg = if !range.contains(0) { + "must be non-null" + } else if init == InitKind::Uninit && !scalar.is_always_valid(cx) { + // Prefer reporting on the fields over the entire struct for uninit, + // as the information bubbles out and it may be unclear why the type can't + // be null from just its outside signature. + + "must be initialized inside its custom valid range" + } else { + return field_err; + }; + if let Some(field_err) = &mut field_err { + // Most of the time, if the field error is the same as the struct error, + // the struct error only happens because of the field error. + if field_err.message.contains(msg) { + field_err.message = format!("because {}", field_err.message); + } + } + return Some(InitError::from(format!("`{ty}` {msg}")).nested(field_err)); + } + } + field_err } /// Return `Some` only if we are sure this type does *not* @@ -2493,63 +2622,36 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { use rustc_type_ir::sty::TyKind::*; match ty.kind() { // Primitive types that don't like 0 as a value. - Ref(..) => Some(("references must be non-null".to_string(), None)), - Adt(..) if ty.is_box() => Some(("`Box` must be non-null".to_string(), None)), - FnPtr(..) => Some(("function pointers must be non-null".to_string(), None)), - Never => Some(("the `!` type has no valid value".to_string(), None)), + Ref(..) => Some("references must be non-null".into()), + Adt(..) if ty.is_box() => Some("`Box` must be non-null".into()), + FnPtr(..) => Some("function pointers must be non-null".into()), + Never => Some("the `!` type has no valid value".into()), RawPtr(tm) if matches!(tm.ty.kind(), Dynamic(..)) => // raw ptr to dyn Trait { - Some(("the vtable of a wide raw pointer must be non-null".to_string(), None)) + Some("the vtable of a wide raw pointer must be non-null".into()) } // Primitive types with other constraints. Bool if init == InitKind::Uninit => { - Some(("booleans must be either `true` or `false`".to_string(), None)) + Some("booleans must be either `true` or `false`".into()) } Char if init == InitKind::Uninit => { - Some(("characters must be a valid Unicode codepoint".to_string(), None)) + Some("characters must be a valid Unicode codepoint".into()) } Int(_) | Uint(_) if init == InitKind::Uninit => { - Some(("integers must not be uninitialized".to_string(), None)) - } - Float(_) if init == InitKind::Uninit => { - Some(("floats must not be uninitialized".to_string(), None)) + Some("integers must be initialized".into()) } + Float(_) if init == InitKind::Uninit => Some("floats must be initialized".into()), RawPtr(_) if init == InitKind::Uninit => { - Some(("raw pointers must not be uninitialized".to_string(), None)) + Some("raw pointers must be initialized".into()) } // Recurse and checks for some compound types. (but not unions) Adt(adt_def, substs) if !adt_def.is_union() => { - // First check if this ADT has a layout attribute (like `NonNull` and friends). - use std::ops::Bound; - match cx.tcx.layout_scalar_valid_range(adt_def.did()) { - // We exploit here that `layout_scalar_valid_range` will never - // return `Bound::Excluded`. (And we have tests checking that we - // handle the attribute correctly.) - // We don't add a span since users cannot declare such types anyway. - (Bound::Included(lo), Bound::Included(hi)) if 0 < lo && lo < hi => { - return Some((format!("`{}` must be non-null", ty), None)); - } - (Bound::Included(lo), Bound::Unbounded) if 0 < lo => { - return Some((format!("`{}` must be non-null", ty), None)); - } - (Bound::Included(_), _) | (_, Bound::Included(_)) - if init == InitKind::Uninit => - { - return Some(( - format!( - "`{}` must be initialized inside its custom valid range", - ty, - ), - None, - )); - } - _ => {} - } // Handle structs. if adt_def.is_struct() { return variant_find_init_error( cx, + ty, adt_def.non_enum_variant(), substs, "struct field", @@ -2573,13 +2675,14 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { Some((variant, definitely_inhabited)) }); let Some(first_variant) = potential_variants.next() else { - return Some(("enums with no inhabited variants have no valid value".to_string(), Some(span))); + return Some(InitError::from("enums with no inhabited variants have no valid value").spanned(span)); }; // So we have at least one potentially inhabited variant. Might we have two? let Some(second_variant) = potential_variants.next() else { // There is only one potentially inhabited variant. So we can recursively check that variant! return variant_find_init_error( cx, + ty, &first_variant.0, substs, "field of the only potentially inhabited enum variant", @@ -2597,10 +2700,9 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { .filter(|(_variant, definitely_inhabited)| *definitely_inhabited) .count(); if definitely_inhabited > 1 { - return Some(( - "enums with multiple inhabited variants have to be initialized to a variant".to_string(), - Some(span), - )); + return Some(InitError::from( + "enums with multiple inhabited variants have to be initialized to a variant", + ).spanned(span)); } } // We couldn't find anything wrong here. @@ -2629,8 +2731,7 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { // using zeroed or uninitialized memory. // We are extremely conservative with what we warn about. let conjured_ty = cx.typeck_results().expr_ty(expr); - if let Some((msg, span)) = - with_no_trimmed_paths!(ty_find_init_error(cx, conjured_ty, init)) + if let Some(mut err) = with_no_trimmed_paths!(ty_find_init_error(cx, conjured_ty, init)) { // FIXME(davidtwco): make translatable cx.struct_span_lint( @@ -2656,10 +2757,17 @@ impl<'tcx> LateLintPass<'tcx> for InvalidValue { "help: use `MaybeUninit` instead, \ and only call `assume_init` after initialization is done", ); - if let Some(span) = span { - lint.span_note(span, &msg); - } else { - lint.note(&msg); + loop { + if let Some(span) = err.span { + lint.span_note(span, &err.message); + } else { + lint.note(&err.message); + } + if let Some(e) = err.nested { + err = *e; + } else { + break; + } } lint }, -- cgit v1.2.3