| use rustc_ast as ast; |
| use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor}; |
| use rustc_ast::{NodeId, PatKind, attr, token}; |
| use rustc_feature::{AttributeGate, BUILTIN_ATTRIBUTE_MAP, BuiltinAttribute, Features}; |
| use rustc_session::Session; |
| use rustc_session::parse::{feature_err, feature_warn}; |
| use rustc_span::source_map::Spanned; |
| use rustc_span::{Span, Symbol, sym}; |
| use thin_vec::ThinVec; |
| |
| use crate::errors; |
| |
| /// The common case. |
| macro_rules! gate { |
| ($visitor:expr, $feature:ident, $span:expr, $explain:expr) => {{ |
| if !$visitor.features.$feature() && !$span.allows_unstable(sym::$feature) { |
| #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable |
| feature_err(&$visitor.sess, sym::$feature, $span, $explain).emit(); |
| } |
| }}; |
| ($visitor:expr, $feature:ident, $span:expr, $explain:expr, $help:expr) => {{ |
| if !$visitor.features.$feature() && !$span.allows_unstable(sym::$feature) { |
| // FIXME: make this translatable |
| #[allow(rustc::diagnostic_outside_of_impl)] |
| #[allow(rustc::untranslatable_diagnostic)] |
| feature_err(&$visitor.sess, sym::$feature, $span, $explain).with_help($help).emit(); |
| } |
| }}; |
| } |
| |
| /// The unusual case, where the `has_feature` condition is non-standard. |
| macro_rules! gate_alt { |
| ($visitor:expr, $has_feature:expr, $name:expr, $span:expr, $explain:expr) => {{ |
| if !$has_feature && !$span.allows_unstable($name) { |
| #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable |
| feature_err(&$visitor.sess, $name, $span, $explain).emit(); |
| } |
| }}; |
| ($visitor:expr, $has_feature:expr, $name:expr, $span:expr, $explain:expr, $notes: expr) => {{ |
| if !$has_feature && !$span.allows_unstable($name) { |
| #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable |
| let mut diag = feature_err(&$visitor.sess, $name, $span, $explain); |
| for note in $notes { |
| diag.note(*note); |
| } |
| diag.emit(); |
| } |
| }}; |
| } |
| |
| /// The case involving a multispan. |
| macro_rules! gate_multi { |
| ($visitor:expr, $feature:ident, $spans:expr, $explain:expr) => {{ |
| if !$visitor.features.$feature() { |
| let spans: Vec<_> = |
| $spans.filter(|span| !span.allows_unstable(sym::$feature)).collect(); |
| if !spans.is_empty() { |
| feature_err(&$visitor.sess, sym::$feature, spans, $explain).emit(); |
| } |
| } |
| }}; |
| } |
| |
| /// The legacy case. |
| macro_rules! gate_legacy { |
| ($visitor:expr, $feature:ident, $span:expr, $explain:expr) => {{ |
| if !$visitor.features.$feature() && !$span.allows_unstable(sym::$feature) { |
| feature_warn(&$visitor.sess, sym::$feature, $span, $explain); |
| } |
| }}; |
| } |
| |
| pub fn check_attribute(attr: &ast::Attribute, sess: &Session, features: &Features) { |
| PostExpansionVisitor { sess, features }.visit_attribute(attr) |
| } |
| |
| struct PostExpansionVisitor<'a> { |
| sess: &'a Session, |
| |
| // `sess` contains a `Features`, but this might not be that one. |
| features: &'a Features, |
| } |
| |
| impl<'a> PostExpansionVisitor<'a> { |
| /// Feature gate `impl Trait` inside `type Alias = $type_expr;`. |
| fn check_impl_trait(&self, ty: &ast::Ty, in_associated_ty: bool) { |
| struct ImplTraitVisitor<'a> { |
| vis: &'a PostExpansionVisitor<'a>, |
| in_associated_ty: bool, |
| } |
| impl Visitor<'_> for ImplTraitVisitor<'_> { |
| fn visit_ty(&mut self, ty: &ast::Ty) { |
| if let ast::TyKind::ImplTrait(..) = ty.kind { |
| if self.in_associated_ty { |
| gate!( |
| &self.vis, |
| impl_trait_in_assoc_type, |
| ty.span, |
| "`impl Trait` in associated types is unstable" |
| ); |
| } else { |
| gate!( |
| &self.vis, |
| type_alias_impl_trait, |
| ty.span, |
| "`impl Trait` in type aliases is unstable" |
| ); |
| } |
| } |
| visit::walk_ty(self, ty); |
| } |
| |
| fn visit_anon_const(&mut self, _: &ast::AnonConst) -> Self::Result { |
| // We don't walk the anon const because it crosses a conceptual boundary: We're no |
| // longer "inside" the original type. |
| // Brittle: We assume that the callers of `check_impl_trait` will later recurse into |
| // the items found in the AnonConst to look for nested TyAliases. |
| } |
| } |
| ImplTraitVisitor { vis: self, in_associated_ty }.visit_ty(ty); |
| } |
| |
| fn check_late_bound_lifetime_defs(&self, params: &[ast::GenericParam]) { |
| // Check only lifetime parameters are present and that the |
| // generic parameters that are present have no bounds. |
| let non_lt_param_spans = params.iter().filter_map(|param| match param.kind { |
| ast::GenericParamKind::Lifetime { .. } => None, |
| _ => Some(param.ident.span), |
| }); |
| gate_multi!( |
| &self, |
| non_lifetime_binders, |
| non_lt_param_spans, |
| crate::fluent_generated::ast_passes_forbidden_non_lifetime_param |
| ); |
| |
| // FIXME(non_lifetime_binders): Const bound params are pretty broken. |
| // Let's keep users from using this feature accidentally. |
| if self.features.non_lifetime_binders() { |
| let const_param_spans: Vec<_> = params |
| .iter() |
| .filter_map(|param| match param.kind { |
| ast::GenericParamKind::Const { .. } => Some(param.ident.span), |
| _ => None, |
| }) |
| .collect(); |
| |
| if !const_param_spans.is_empty() { |
| self.sess.dcx().emit_err(errors::ForbiddenConstParam { const_param_spans }); |
| } |
| } |
| |
| for param in params { |
| if !param.bounds.is_empty() { |
| let spans: Vec<_> = param.bounds.iter().map(|b| b.span()).collect(); |
| self.sess.dcx().emit_err(errors::ForbiddenBound { spans }); |
| } |
| } |
| } |
| } |
| |
| impl<'a> Visitor<'a> for PostExpansionVisitor<'a> { |
| fn visit_attribute(&mut self, attr: &ast::Attribute) { |
| let attr_info = attr.ident().and_then(|ident| BUILTIN_ATTRIBUTE_MAP.get(&ident.name)); |
| // Check feature gates for built-in attributes. |
| if let Some(BuiltinAttribute { |
| gate: AttributeGate::Gated { feature, message, check, notes, .. }, |
| .. |
| }) = attr_info |
| { |
| gate_alt!(self, check(self.features), *feature, attr.span, *message, *notes); |
| } |
| // Check unstable flavors of the `#[doc]` attribute. |
| if attr.has_name(sym::doc) { |
| for meta_item_inner in attr.meta_item_list().unwrap_or_default() { |
| macro_rules! gate_doc { ($($s:literal { $($name:ident => $feature:ident)* })*) => { |
| $($(if meta_item_inner.has_name(sym::$name) { |
| let msg = concat!("`#[doc(", stringify!($name), ")]` is ", $s); |
| gate!(self, $feature, attr.span, msg); |
| })*)* |
| }} |
| |
| gate_doc!( |
| "experimental" { |
| cfg => doc_cfg |
| cfg_hide => doc_cfg_hide |
| masked => doc_masked |
| notable_trait => doc_notable_trait |
| } |
| "meant for internal use only" { |
| attribute => rustdoc_internals |
| keyword => rustdoc_internals |
| fake_variadic => rustdoc_internals |
| search_unbox => rustdoc_internals |
| } |
| ); |
| } |
| } |
| } |
| |
| fn visit_item(&mut self, i: &'a ast::Item) { |
| match &i.kind { |
| ast::ItemKind::ForeignMod(_foreign_module) => { |
| // handled during lowering |
| } |
| ast::ItemKind::Struct(..) | ast::ItemKind::Enum(..) | ast::ItemKind::Union(..) => { |
| for attr in attr::filter_by_name(&i.attrs, sym::repr) { |
| for item in attr.meta_item_list().unwrap_or_else(ThinVec::new) { |
| if item.has_name(sym::simd) { |
| gate!( |
| &self, |
| repr_simd, |
| attr.span, |
| "SIMD types are experimental and possibly buggy" |
| ); |
| } |
| } |
| } |
| } |
| |
| ast::ItemKind::Impl(ast::Impl { of_trait: Some(of_trait), .. }) => { |
| if let ast::ImplPolarity::Negative(span) = of_trait.polarity { |
| gate!( |
| &self, |
| negative_impls, |
| span.to(of_trait.trait_ref.path.span), |
| "negative trait bounds are not fully implemented; \ |
| use marker types for now" |
| ); |
| } |
| |
| if let ast::Defaultness::Default(_) = of_trait.defaultness { |
| gate!(&self, specialization, i.span, "specialization is unstable"); |
| } |
| } |
| |
| ast::ItemKind::Trait(box ast::Trait { is_auto: ast::IsAuto::Yes, .. }) => { |
| gate!( |
| &self, |
| auto_traits, |
| i.span, |
| "auto traits are experimental and possibly buggy" |
| ); |
| } |
| |
| ast::ItemKind::TraitAlias(..) => { |
| gate!(&self, trait_alias, i.span, "trait aliases are experimental"); |
| } |
| |
| ast::ItemKind::MacroDef(_, ast::MacroDef { macro_rules: false, .. }) => { |
| let msg = "`macro` is experimental"; |
| gate!(&self, decl_macro, i.span, msg); |
| } |
| |
| ast::ItemKind::TyAlias(box ast::TyAlias { ty: Some(ty), .. }) => { |
| self.check_impl_trait(ty, false) |
| } |
| |
| _ => {} |
| } |
| |
| visit::walk_item(self, i); |
| } |
| |
| fn visit_foreign_item(&mut self, i: &'a ast::ForeignItem) { |
| match i.kind { |
| ast::ForeignItemKind::Fn(..) | ast::ForeignItemKind::Static(..) => { |
| let link_name = attr::first_attr_value_str_by_name(&i.attrs, sym::link_name); |
| let links_to_llvm = link_name.is_some_and(|val| val.as_str().starts_with("llvm.")); |
| if links_to_llvm { |
| gate!( |
| &self, |
| link_llvm_intrinsics, |
| i.span, |
| "linking to LLVM intrinsics is experimental" |
| ); |
| } |
| } |
| ast::ForeignItemKind::TyAlias(..) => { |
| gate!(&self, extern_types, i.span, "extern types are experimental"); |
| } |
| ast::ForeignItemKind::MacCall(..) => {} |
| } |
| |
| visit::walk_item(self, i) |
| } |
| |
| fn visit_ty(&mut self, ty: &'a ast::Ty) { |
| match &ty.kind { |
| ast::TyKind::FnPtr(fn_ptr_ty) => { |
| // Function pointers cannot be `const` |
| self.check_late_bound_lifetime_defs(&fn_ptr_ty.generic_params); |
| } |
| ast::TyKind::Never => { |
| gate!(&self, never_type, ty.span, "the `!` type is experimental"); |
| } |
| ast::TyKind::Pat(..) => { |
| gate!(&self, pattern_types, ty.span, "pattern types are unstable"); |
| } |
| _ => {} |
| } |
| visit::walk_ty(self, ty) |
| } |
| |
| fn visit_generics(&mut self, g: &'a ast::Generics) { |
| for predicate in &g.where_clause.predicates { |
| match &predicate.kind { |
| ast::WherePredicateKind::BoundPredicate(bound_pred) => { |
| // A type bound (e.g., `for<'c> Foo: Send + Clone + 'c`). |
| self.check_late_bound_lifetime_defs(&bound_pred.bound_generic_params); |
| } |
| _ => {} |
| } |
| } |
| visit::walk_generics(self, g); |
| } |
| |
| fn visit_fn_ret_ty(&mut self, ret_ty: &'a ast::FnRetTy) { |
| if let ast::FnRetTy::Ty(output_ty) = ret_ty { |
| if let ast::TyKind::Never = output_ty.kind { |
| // Do nothing. |
| } else { |
| self.visit_ty(output_ty) |
| } |
| } |
| } |
| |
| fn visit_generic_args(&mut self, args: &'a ast::GenericArgs) { |
| // This check needs to happen here because the never type can be returned from a function, |
| // but cannot be used in any other context. If this check was in `visit_fn_ret_ty`, it |
| // include both functions and generics like `impl Fn() -> !`. |
| if let ast::GenericArgs::Parenthesized(generic_args) = args |
| && let ast::FnRetTy::Ty(ref ty) = generic_args.output |
| && matches!(ty.kind, ast::TyKind::Never) |
| { |
| gate!(&self, never_type, ty.span, "the `!` type is experimental"); |
| } |
| visit::walk_generic_args(self, args); |
| } |
| |
| fn visit_expr(&mut self, e: &'a ast::Expr) { |
| match e.kind { |
| ast::ExprKind::TryBlock(_) => { |
| gate!(&self, try_blocks, e.span, "`try` expression is experimental"); |
| } |
| ast::ExprKind::Lit(token::Lit { |
| kind: token::LitKind::Float | token::LitKind::Integer, |
| suffix, |
| .. |
| }) => match suffix { |
| Some(sym::f16) => { |
| gate!(&self, f16, e.span, "the type `f16` is unstable") |
| } |
| Some(sym::f128) => { |
| gate!(&self, f128, e.span, "the type `f128` is unstable") |
| } |
| _ => (), |
| }, |
| _ => {} |
| } |
| visit::walk_expr(self, e) |
| } |
| |
| fn visit_pat(&mut self, pattern: &'a ast::Pat) { |
| match &pattern.kind { |
| PatKind::Slice(pats) => { |
| for pat in pats { |
| let inner_pat = match &pat.kind { |
| PatKind::Ident(.., Some(pat)) => pat, |
| _ => pat, |
| }; |
| if let PatKind::Range(Some(_), None, Spanned { .. }) = inner_pat.kind { |
| gate!( |
| &self, |
| half_open_range_patterns_in_slices, |
| pat.span, |
| "`X..` patterns in slices are experimental" |
| ); |
| } |
| } |
| } |
| PatKind::Box(..) => { |
| gate!(&self, box_patterns, pattern.span, "box pattern syntax is experimental"); |
| } |
| _ => {} |
| } |
| visit::walk_pat(self, pattern) |
| } |
| |
| fn visit_poly_trait_ref(&mut self, t: &'a ast::PolyTraitRef) { |
| self.check_late_bound_lifetime_defs(&t.bound_generic_params); |
| visit::walk_poly_trait_ref(self, t); |
| } |
| |
| fn visit_fn(&mut self, fn_kind: FnKind<'a>, span: Span, _: NodeId) { |
| if let Some(_header) = fn_kind.header() { |
| // Stability of const fn methods are covered in `visit_assoc_item` below. |
| } |
| |
| if let FnKind::Closure(ast::ClosureBinder::For { generic_params, .. }, ..) = fn_kind { |
| self.check_late_bound_lifetime_defs(generic_params); |
| } |
| |
| if fn_kind.ctxt() != Some(FnCtxt::Foreign) && fn_kind.decl().c_variadic() { |
| gate!(&self, c_variadic, span, "C-variadic functions are unstable"); |
| } |
| |
| visit::walk_fn(self, fn_kind) |
| } |
| |
| fn visit_assoc_item(&mut self, i: &'a ast::AssocItem, ctxt: AssocCtxt) { |
| let is_fn = match &i.kind { |
| ast::AssocItemKind::Fn(_) => true, |
| ast::AssocItemKind::Type(box ast::TyAlias { ty, .. }) => { |
| if let (Some(_), AssocCtxt::Trait) = (ty, ctxt) { |
| gate!( |
| &self, |
| associated_type_defaults, |
| i.span, |
| "associated type defaults are unstable" |
| ); |
| } |
| if let Some(ty) = ty { |
| self.check_impl_trait(ty, true); |
| } |
| false |
| } |
| _ => false, |
| }; |
| if let ast::Defaultness::Default(_) = i.kind.defaultness() { |
| // Limit `min_specialization` to only specializing functions. |
| gate_alt!( |
| &self, |
| self.features.specialization() || (is_fn && self.features.min_specialization()), |
| sym::specialization, |
| i.span, |
| "specialization is unstable" |
| ); |
| } |
| visit::walk_assoc_item(self, i, ctxt) |
| } |
| } |
| |
| pub fn check_crate(krate: &ast::Crate, sess: &Session, features: &Features) { |
| maybe_stage_features(sess, features, krate); |
| check_incompatible_features(sess, features); |
| check_new_solver_banned_features(sess, features); |
| |
| let mut visitor = PostExpansionVisitor { sess, features }; |
| |
| let spans = sess.psess.gated_spans.spans.borrow(); |
| macro_rules! gate_all { |
| ($gate:ident, $msg:literal) => { |
| if let Some(spans) = spans.get(&sym::$gate) { |
| for span in spans { |
| gate!(&visitor, $gate, *span, $msg); |
| } |
| } |
| }; |
| ($gate:ident, $msg:literal, $help:literal) => { |
| if let Some(spans) = spans.get(&sym::$gate) { |
| for span in spans { |
| gate!(&visitor, $gate, *span, $msg, $help); |
| } |
| } |
| }; |
| } |
| gate_all!( |
| if_let_guard, |
| "`if let` guards are experimental", |
| "you can write `if matches!(<expr>, <pattern>)` instead of `if let <pattern> = <expr>`" |
| ); |
| gate_all!( |
| async_trait_bounds, |
| "`async` trait bounds are unstable", |
| "use the desugared name of the async trait, such as `AsyncFn`" |
| ); |
| gate_all!(async_for_loop, "`for await` loops are experimental"); |
| gate_all!( |
| closure_lifetime_binder, |
| "`for<...>` binders for closures are experimental", |
| "consider removing `for<...>`" |
| ); |
| gate_all!(more_qualified_paths, "usage of qualified paths in this context is experimental"); |
| // yield can be enabled either by `coroutines` or `gen_blocks` |
| if let Some(spans) = spans.get(&sym::yield_expr) { |
| for span in spans { |
| if (!visitor.features.coroutines() && !span.allows_unstable(sym::coroutines)) |
| && (!visitor.features.gen_blocks() && !span.allows_unstable(sym::gen_blocks)) |
| && (!visitor.features.yield_expr() && !span.allows_unstable(sym::yield_expr)) |
| { |
| #[allow(rustc::untranslatable_diagnostic)] |
| // Emit yield_expr as the error, since that will be sufficient. You can think of it |
| // as coroutines and gen_blocks imply yield_expr. |
| feature_err(&visitor.sess, sym::yield_expr, *span, "yield syntax is experimental") |
| .emit(); |
| } |
| } |
| } |
| gate_all!(gen_blocks, "gen blocks are experimental"); |
| gate_all!(const_trait_impl, "const trait impls are experimental"); |
| gate_all!( |
| half_open_range_patterns_in_slices, |
| "half-open range patterns in slices are unstable" |
| ); |
| gate_all!(associated_const_equality, "associated const equality is incomplete"); |
| gate_all!(yeet_expr, "`do yeet` expression is experimental"); |
| gate_all!(const_closures, "const closures are experimental"); |
| gate_all!(builtin_syntax, "`builtin #` syntax is unstable"); |
| gate_all!(ergonomic_clones, "ergonomic clones are experimental"); |
| gate_all!(explicit_tail_calls, "`become` expression is experimental"); |
| gate_all!(generic_const_items, "generic const items are experimental"); |
| gate_all!(guard_patterns, "guard patterns are experimental", "consider using match arm guards"); |
| gate_all!(default_field_values, "default values on fields are experimental"); |
| gate_all!(fn_delegation, "functions delegation is not yet fully implemented"); |
| gate_all!(postfix_match, "postfix match is experimental"); |
| gate_all!(mut_ref, "mutable by-reference bindings are experimental"); |
| gate_all!(global_registration, "global registration is experimental"); |
| gate_all!(return_type_notation, "return type notation is experimental"); |
| gate_all!(pin_ergonomics, "pinned reference syntax is experimental"); |
| gate_all!(unsafe_fields, "`unsafe` fields are experimental"); |
| gate_all!(unsafe_binders, "unsafe binder types are experimental"); |
| gate_all!(contracts, "contracts are incomplete"); |
| gate_all!(contracts_internals, "contract internal machinery is for internal use only"); |
| gate_all!(where_clause_attrs, "attributes in `where` clause are unstable"); |
| gate_all!(super_let, "`super let` is experimental"); |
| gate_all!(frontmatter, "frontmatters are experimental"); |
| gate_all!(coroutines, "coroutine syntax is experimental"); |
| |
| if !visitor.features.never_patterns() { |
| if let Some(spans) = spans.get(&sym::never_patterns) { |
| for &span in spans { |
| if span.allows_unstable(sym::never_patterns) { |
| continue; |
| } |
| let sm = sess.source_map(); |
| // We gate two types of spans: the span of a `!` pattern, and the span of a |
| // match arm without a body. For the latter we want to give the user a normal |
| // error. |
| if let Ok(snippet) = sm.span_to_snippet(span) |
| && snippet == "!" |
| { |
| #[allow(rustc::untranslatable_diagnostic)] // FIXME: make this translatable |
| feature_err(sess, sym::never_patterns, span, "`!` patterns are experimental") |
| .emit(); |
| } else { |
| let suggestion = span.shrink_to_hi(); |
| sess.dcx().emit_err(errors::MatchArmWithNoBody { span, suggestion }); |
| } |
| } |
| } |
| } |
| |
| if !visitor.features.negative_bounds() { |
| for &span in spans.get(&sym::negative_bounds).iter().copied().flatten() { |
| sess.dcx().emit_err(errors::NegativeBoundUnsupported { span }); |
| } |
| } |
| |
| // All uses of `gate_all_legacy_dont_use!` below this point were added in #65742, |
| // and subsequently disabled (with the non-early gating readded). |
| // We emit an early future-incompatible warning for these. |
| // New syntax gates should go above here to get a hard error gate. |
| macro_rules! gate_all_legacy_dont_use { |
| ($gate:ident, $msg:literal) => { |
| for span in spans.get(&sym::$gate).unwrap_or(&vec![]) { |
| gate_legacy!(&visitor, $gate, *span, $msg); |
| } |
| }; |
| } |
| |
| gate_all_legacy_dont_use!(box_patterns, "box pattern syntax is experimental"); |
| gate_all_legacy_dont_use!(trait_alias, "trait aliases are experimental"); |
| gate_all_legacy_dont_use!(decl_macro, "`macro` is experimental"); |
| gate_all_legacy_dont_use!(try_blocks, "`try` blocks are unstable"); |
| gate_all_legacy_dont_use!(auto_traits, "`auto` traits are unstable"); |
| |
| visit::walk_crate(&mut visitor, krate); |
| } |
| |
| fn maybe_stage_features(sess: &Session, features: &Features, krate: &ast::Crate) { |
| // checks if `#![feature]` has been used to enable any feature. |
| if sess.opts.unstable_features.is_nightly_build() { |
| return; |
| } |
| if features.enabled_features().is_empty() { |
| return; |
| } |
| let mut errored = false; |
| for attr in krate.attrs.iter().filter(|attr| attr.has_name(sym::feature)) { |
| // `feature(...)` used on non-nightly. This is definitely an error. |
| let mut err = errors::FeatureOnNonNightly { |
| span: attr.span, |
| channel: option_env!("CFG_RELEASE_CHANNEL").unwrap_or("(unknown)"), |
| stable_features: vec![], |
| sugg: None, |
| }; |
| |
| let mut all_stable = true; |
| for ident in attr.meta_item_list().into_iter().flatten().flat_map(|nested| nested.ident()) { |
| let name = ident.name; |
| let stable_since = features |
| .enabled_lang_features() |
| .iter() |
| .find(|feat| feat.gate_name == name) |
| .map(|feat| feat.stable_since) |
| .flatten(); |
| if let Some(since) = stable_since { |
| err.stable_features.push(errors::StableFeature { name, since }); |
| } else { |
| all_stable = false; |
| } |
| } |
| if all_stable { |
| err.sugg = Some(attr.span); |
| } |
| sess.dcx().emit_err(err); |
| errored = true; |
| } |
| // Just make sure we actually error if anything is listed in `enabled_features`. |
| assert!(errored); |
| } |
| |
| fn check_incompatible_features(sess: &Session, features: &Features) { |
| let enabled_lang_features = |
| features.enabled_lang_features().iter().map(|feat| (feat.gate_name, feat.attr_sp)); |
| let enabled_lib_features = |
| features.enabled_lib_features().iter().map(|feat| (feat.gate_name, feat.attr_sp)); |
| let enabled_features = enabled_lang_features.chain(enabled_lib_features); |
| |
| for (f1, f2) in rustc_feature::INCOMPATIBLE_FEATURES |
| .iter() |
| .filter(|(f1, f2)| features.enabled(*f1) && features.enabled(*f2)) |
| { |
| if let Some((f1_name, f1_span)) = enabled_features.clone().find(|(name, _)| name == f1) |
| && let Some((f2_name, f2_span)) = enabled_features.clone().find(|(name, _)| name == f2) |
| { |
| let spans = vec![f1_span, f2_span]; |
| sess.dcx().emit_err(errors::IncompatibleFeatures { spans, f1: f1_name, f2: f2_name }); |
| } |
| } |
| } |
| |
| fn check_new_solver_banned_features(sess: &Session, features: &Features) { |
| if !sess.opts.unstable_opts.next_solver.globally { |
| return; |
| } |
| |
| // Ban GCE with the new solver, because it does not implement GCE correctly. |
| if let Some(gce_span) = features |
| .enabled_lang_features() |
| .iter() |
| .find(|feat| feat.gate_name == sym::generic_const_exprs) |
| .map(|feat| feat.attr_sp) |
| { |
| #[allow(rustc::symbol_intern_string_literal)] |
| sess.dcx().emit_err(errors::IncompatibleFeatures { |
| spans: vec![gce_span], |
| f1: Symbol::intern("-Znext-solver=globally"), |
| f2: sym::generic_const_exprs, |
| }); |
| } |
| } |
