diff options
Diffstat (limited to 'compiler/rustc_hir_typeck/src/cast.rs')
| -rw-r--r-- | compiler/rustc_hir_typeck/src/cast.rs | 274 |
1 files changed, 95 insertions, 179 deletions
diff --git a/compiler/rustc_hir_typeck/src/cast.rs b/compiler/rustc_hir_typeck/src/cast.rs index 31a03fabe..2b1ac7f35 100644 --- a/compiler/rustc_hir_typeck/src/cast.rs +++ b/compiler/rustc_hir_typeck/src/cast.rs @@ -30,11 +30,10 @@ use super::FnCtxt; +use crate::errors; use crate::type_error_struct; use hir::ExprKind; -use rustc_errors::{ - struct_span_err, Applicability, DelayDm, Diagnostic, DiagnosticBuilder, ErrorGuaranteed, -}; +use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed}; use rustc_hir as hir; use rustc_macros::{TypeFoldable, TypeVisitable}; use rustc_middle::mir::Mutability; @@ -130,7 +129,6 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { | ty::Float(_) | ty::Array(..) | ty::GeneratorWitness(..) - | ty::GeneratorWitnessMIR(..) | ty::RawPtr(_) | ty::Ref(..) | ty::FnDef(..) @@ -321,28 +319,15 @@ impl<'a, 'tcx> CastCheck<'tcx> { .emit(); } CastError::CastToBool => { - let mut err = - struct_span_err!(fcx.tcx.sess, self.span, E0054, "cannot cast as `bool`"); - - if self.expr_ty.is_numeric() { - match fcx.tcx.sess.source_map().span_to_snippet(self.expr_span) { - Ok(snippet) => { - err.span_suggestion( - self.span, - "compare with zero instead", - format!("{snippet} != 0"), - Applicability::MachineApplicable, - ); - } - Err(_) => { - err.span_help(self.span, "compare with zero instead"); - } - } + let expr_ty = fcx.resolve_vars_if_possible(self.expr_ty); + let help = if self.expr_ty.is_numeric() { + errors::CannotCastToBoolHelp::Numeric( + self.expr_span.shrink_to_hi().with_hi(self.span.hi()), + ) } else { - err.span_label(self.span, "unsupported cast"); - } - - err.emit(); + errors::CannotCastToBoolHelp::Unsupported(self.span) + }; + fcx.tcx.sess.emit_err(errors::CannotCastToBool { span: self.span, expr_ty, help }); } CastError::CastToChar => { let mut err = type_error_struct!( @@ -531,33 +516,20 @@ impl<'a, 'tcx> CastCheck<'tcx> { .emit(); } CastError::IntToFatCast(known_metadata) => { - let mut err = struct_span_err!( - fcx.tcx.sess, - self.cast_span, - E0606, - "cannot cast `{}` to a pointer that {} wide", - fcx.ty_to_string(self.expr_ty), - if known_metadata.is_some() { "is" } else { "may be" } - ); - - err.span_label( - self.cast_span, - format!( - "creating a `{}` requires both an address and {}", - self.cast_ty, - known_metadata.unwrap_or("type-specific metadata"), - ), - ); - - if fcx.tcx.sess.is_nightly_build() { - err.span_label( - self.expr_span, - "consider casting this expression to `*const ()`, \ - then using `core::ptr::from_raw_parts`", - ); - } - - err.emit(); + let expr_if_nightly = fcx.tcx.sess.is_nightly_build().then_some(self.expr_span); + let cast_ty = fcx.resolve_vars_if_possible(self.cast_ty); + let expr_ty = fcx.ty_to_string(self.expr_ty); + let metadata = known_metadata.unwrap_or("type-specific metadata"); + let known_wide = known_metadata.is_some(); + let span = self.cast_span; + fcx.tcx.sess.emit_err(errors::IntToWide { + span, + metadata, + expr_ty, + cast_ty, + expr_if_nightly, + known_wide, + }); } CastError::UnknownCastPtrKind | CastError::UnknownExprPtrKind => { let unknown_cast_to = match e { @@ -565,27 +537,16 @@ impl<'a, 'tcx> CastCheck<'tcx> { CastError::UnknownExprPtrKind => false, _ => bug!(), }; - let mut err = struct_span_err!( - fcx.tcx.sess, - if unknown_cast_to { self.cast_span } else { self.span }, - E0641, - "cannot cast {} a pointer of an unknown kind", - if unknown_cast_to { "to" } else { "from" } - ); - if unknown_cast_to { - err.span_label(self.cast_span, "needs more type information"); - err.note( - "the type information given here is insufficient to check whether \ - the pointer cast is valid", - ); + let (span, sub) = if unknown_cast_to { + (self.cast_span, errors::CastUnknownPointerSub::To(self.cast_span)) } else { - err.span_label( - self.span, - "the type information given here is insufficient to check whether \ - the pointer cast is valid", - ); - } - err.emit(); + (self.cast_span, errors::CastUnknownPointerSub::From(self.span)) + }; + fcx.tcx.sess.emit_err(errors::CastUnknownPointer { + span, + to: unknown_cast_to, + sub, + }); } CastError::ForeignNonExhaustiveAdt => { make_invalid_casting_error( @@ -669,31 +630,18 @@ impl<'a, 'tcx> CastCheck<'tcx> { } fn trivial_cast_lint(&self, fcx: &FnCtxt<'a, 'tcx>) { - let t_cast = self.cast_ty; - let t_expr = self.expr_ty; - let (adjective, lint) = if t_cast.is_numeric() && t_expr.is_numeric() { - ("numeric ", lint::builtin::TRIVIAL_NUMERIC_CASTS) + let (numeric, lint) = if self.cast_ty.is_numeric() && self.expr_ty.is_numeric() { + (true, lint::builtin::TRIVIAL_NUMERIC_CASTS) } else { - ("", lint::builtin::TRIVIAL_CASTS) + (false, lint::builtin::TRIVIAL_CASTS) }; - fcx.tcx.struct_span_lint_hir( + let expr_ty = fcx.resolve_vars_if_possible(self.expr_ty); + let cast_ty = fcx.resolve_vars_if_possible(self.cast_ty); + fcx.tcx.emit_spanned_lint( lint, self.expr.hir_id, self.span, - DelayDm(|| { - format!( - "trivial {}cast: `{}` as `{}`", - adjective, - fcx.ty_to_string(t_expr), - fcx.ty_to_string(t_cast) - ) - }), - |lint| { - lint.help( - "cast can be replaced by coercion; this might \ - require a temporary variable", - ) - }, + errors::TrivialCast { numeric, expr_ty, cast_ty }, ); } @@ -776,6 +724,9 @@ impl<'a, 'tcx> CastCheck<'tcx> { }, // array-ptr-cast Ptr(mt) => { + if !fcx.type_is_sized_modulo_regions(fcx.param_env, mt.ty) { + return Err(CastError::IllegalCast); + } self.check_ref_cast(fcx, TypeAndMut { mutbl, ty: inner_ty }, mt) } _ => Err(CastError::NonScalar), @@ -786,7 +737,6 @@ impl<'a, 'tcx> CastCheck<'tcx> { } _ => return Err(CastError::NonScalar), }; - if let ty::Adt(adt_def, _) = *self.expr_ty.kind() { if adt_def.did().krate != LOCAL_CRATE { if adt_def.variants().iter().any(VariantDef::is_field_list_non_exhaustive) { @@ -794,7 +744,6 @@ impl<'a, 'tcx> CastCheck<'tcx> { } } } - match (t_from, t_cast) { // These types have invariants! can't cast into them. (_, Int(CEnum) | FnPtr) => Err(CastError::NonScalar), @@ -986,93 +935,67 @@ impl<'a, 'tcx> CastCheck<'tcx> { if let ty::Adt(d, _) = self.expr_ty.kind() && d.has_dtor(fcx.tcx) { - fcx.tcx.struct_span_lint_hir( + let expr_ty = fcx.resolve_vars_if_possible(self.expr_ty); + let cast_ty = fcx.resolve_vars_if_possible(self.cast_ty); + + fcx.tcx.emit_spanned_lint( lint::builtin::CENUM_IMPL_DROP_CAST, self.expr.hir_id, self.span, - DelayDm(|| format!( - "cannot cast enum `{}` into integer `{}` because it implements `Drop`", - self.expr_ty, self.cast_ty - )), - |lint| { - lint - }, + errors::CastEnumDrop { + expr_ty, + cast_ty, + } ); } } fn lossy_provenance_ptr2int_lint(&self, fcx: &FnCtxt<'a, 'tcx>, t_c: ty::cast::IntTy) { - fcx.tcx.struct_span_lint_hir( + let expr_prec = self.expr.precedence().order(); + let needs_parens = expr_prec < rustc_ast::util::parser::PREC_POSTFIX; + + let needs_cast = !matches!(t_c, ty::cast::IntTy::U(ty::UintTy::Usize)); + let cast_span = self.expr_span.shrink_to_hi().to(self.cast_span); + let expr_ty = fcx.resolve_vars_if_possible(self.expr_ty); + let cast_ty = fcx.resolve_vars_if_possible(self.cast_ty); + let expr_span = self.expr_span.shrink_to_lo(); + let sugg = match (needs_parens, needs_cast) { + (true, true) => errors::LossyProvenancePtr2IntSuggestion::NeedsParensCast { + expr_span, + cast_span, + cast_ty, + }, + (true, false) => { + errors::LossyProvenancePtr2IntSuggestion::NeedsParens { expr_span, cast_span } + } + (false, true) => { + errors::LossyProvenancePtr2IntSuggestion::NeedsCast { cast_span, cast_ty } + } + (false, false) => errors::LossyProvenancePtr2IntSuggestion::Other { cast_span }, + }; + + let lint = errors::LossyProvenancePtr2Int { expr_ty, cast_ty, sugg }; + fcx.tcx.emit_spanned_lint( lint::builtin::LOSSY_PROVENANCE_CASTS, self.expr.hir_id, self.span, - DelayDm(|| format!( - "under strict provenance it is considered bad style to cast pointer `{}` to integer `{}`", - self.expr_ty, self.cast_ty - )), - |lint| { - let msg = "use `.addr()` to obtain the address of a pointer"; - - let expr_prec = self.expr.precedence().order(); - let needs_parens = expr_prec < rustc_ast::util::parser::PREC_POSTFIX; - - let scalar_cast = match t_c { - ty::cast::IntTy::U(ty::UintTy::Usize) => String::new(), - _ => format!(" as {}", self.cast_ty), - }; - - let cast_span = self.expr_span.shrink_to_hi().to(self.cast_span); - - if needs_parens { - let suggestions = vec![ - (self.expr_span.shrink_to_lo(), String::from("(")), - (cast_span, format!(").addr(){scalar_cast}")), - ]; - - lint.multipart_suggestion(msg, suggestions, Applicability::MaybeIncorrect); - } else { - lint.span_suggestion( - cast_span, - msg, - format!(".addr(){scalar_cast}"), - Applicability::MaybeIncorrect, - ); - } - - lint.help( - "if you can't comply with strict provenance and need to expose the pointer \ - provenance you can use `.expose_addr()` instead" - ); - - lint - }, + lint, ); } fn fuzzy_provenance_int2ptr_lint(&self, fcx: &FnCtxt<'a, 'tcx>) { - fcx.tcx.struct_span_lint_hir( + let sugg = errors::LossyProvenanceInt2PtrSuggestion { + lo: self.expr_span.shrink_to_lo(), + hi: self.expr_span.shrink_to_hi().to(self.cast_span), + }; + let expr_ty = fcx.resolve_vars_if_possible(self.expr_ty); + let cast_ty = fcx.resolve_vars_if_possible(self.cast_ty); + let lint = errors::LossyProvenanceInt2Ptr { expr_ty, cast_ty, sugg }; + fcx.tcx.emit_spanned_lint( lint::builtin::FUZZY_PROVENANCE_CASTS, self.expr.hir_id, self.span, - DelayDm(|| format!( - "strict provenance disallows casting integer `{}` to pointer `{}`", - self.expr_ty, self.cast_ty - )), - |lint| { - let msg = "use `.with_addr()` to adjust a valid pointer in the same allocation, to this address"; - let suggestions = vec![ - (self.expr_span.shrink_to_lo(), String::from("(...).with_addr(")), - (self.expr_span.shrink_to_hi().to(self.cast_span), String::from(")")), - ]; - - lint.multipart_suggestion(msg, suggestions, Applicability::MaybeIncorrect); - lint.help( - "if you can't comply with strict provenance and don't have a pointer with \ - the correct provenance you can use `std::ptr::from_exposed_addr()` instead" - ); - - lint - }, + lint, ); } @@ -1088,26 +1011,19 @@ impl<'a, 'tcx> CastCheck<'tcx> { if let Some((deref_ty, _)) = derefed { // Give a note about what the expr derefs to. if deref_ty != self.expr_ty.peel_refs() { - err.span_note( - self.expr_span, - format!( - "this expression `Deref`s to `{}` which implements `is_empty`", - fcx.ty_to_string(deref_ty) - ), - ); + err.subdiagnostic(errors::DerefImplsIsEmpty { + span: self.expr_span, + deref_ty: fcx.ty_to_string(deref_ty), + }); } // Create a multipart suggestion: add `!` and `.is_empty()` in // place of the cast. - let suggestion = vec![ - (self.expr_span.shrink_to_lo(), "!".to_string()), - (self.span.with_lo(self.expr_span.hi()), ".is_empty()".to_string()), - ]; - - err.multipart_suggestion_verbose(format!( - "consider using the `is_empty` method on `{}` to determine if it contains anything", - fcx.ty_to_string(self.expr_ty), - ), suggestion, Applicability::MaybeIncorrect); + err.subdiagnostic(errors::UseIsEmpty { + lo: self.expr_span.shrink_to_lo(), + hi: self.span.with_lo(self.expr_span.hi()), + expr_ty: fcx.ty_to_string(self.expr_ty), + }); } } } |