diff options
Diffstat (limited to 'compiler/rustc_const_eval/src/transform/check_consts')
4 files changed, 61 insertions, 82 deletions
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/check.rs b/compiler/rustc_const_eval/src/transform/check_consts/check.rs index 22a61774e..54213d55a 100644 --- a/compiler/rustc_const_eval/src/transform/check_consts/check.rs +++ b/compiler/rustc_const_eval/src/transform/check_consts/check.rs @@ -10,14 +10,11 @@ use rustc_middle::mir::visit::{MutatingUseContext, NonMutatingUseContext, PlaceC use rustc_middle::mir::*; use rustc_middle::ty::subst::{GenericArgKind, InternalSubsts}; use rustc_middle::ty::{self, adjustment::PointerCast, Instance, InstanceDef, Ty, TyCtxt}; -use rustc_middle::ty::{Binder, TraitPredicate, TraitRef, TypeVisitable}; +use rustc_middle::ty::{Binder, TraitRef, TypeVisitable}; use rustc_mir_dataflow::{self, Analysis}; use rustc_span::{sym, Span, Symbol}; -use rustc_trait_selection::infer::InferCtxtExt; use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _; -use rustc_trait_selection::traits::{ - self, ObligationCauseCode, SelectionContext, TraitEngine, TraitEngineExt, -}; +use rustc_trait_selection::traits::{self, ObligationCauseCode, ObligationCtxt, SelectionContext}; use std::mem; use std::ops::Deref; @@ -452,8 +449,17 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { | Rvalue::CopyForDeref(..) | Rvalue::Repeat(..) | Rvalue::Discriminant(..) - | Rvalue::Len(_) - | Rvalue::Aggregate(..) => {} + | Rvalue::Len(_) => {} + + Rvalue::Aggregate(ref kind, ..) => { + if let AggregateKind::Generator(def_id, ..) = kind.as_ref() { + if let Some(generator_kind) = self.tcx.generator_kind(def_id.to_def_id()) { + if matches!(generator_kind, hir::GeneratorKind::Async(..)) { + self.check_op(ops::Generator(generator_kind)); + } + } + } + } Rvalue::Ref(_, kind @ BorrowKind::Mut { .. }, ref place) | Rvalue::Ref(_, kind @ BorrowKind::Unique, ref place) => { @@ -729,13 +735,10 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } let trait_ref = TraitRef::from_method(tcx, trait_id, substs); - let poly_trait_pred = Binder::dummy(TraitPredicate { - trait_ref, - constness: ty::BoundConstness::ConstIfConst, - polarity: ty::ImplPolarity::Positive, - }); + let poly_trait_pred = + Binder::dummy(trait_ref).with_constness(ty::BoundConstness::ConstIfConst); let obligation = - Obligation::new(ObligationCause::dummy(), param_env, poly_trait_pred); + Obligation::new(tcx, ObligationCause::dummy(), param_env, poly_trait_pred); let implsrc = { let infcx = tcx.infer_ctxt().build(); @@ -747,37 +750,27 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // "non-const" check. This is required for correctness here. { let infcx = tcx.infer_ctxt().build(); - let mut fulfill_cx = <dyn TraitEngine<'_>>::new(infcx.tcx); + let ocx = ObligationCtxt::new(&infcx); + let predicates = tcx.predicates_of(callee).instantiate(tcx, substs); let hir_id = tcx .hir() .local_def_id_to_hir_id(self.body.source.def_id().expect_local()); - let cause = || { - ObligationCause::new( - terminator.source_info.span, - hir_id, - ObligationCauseCode::ItemObligation(callee), - ) - }; - let normalized = infcx.partially_normalize_associated_types_in( - cause(), - param_env, - predicates, + let cause = ObligationCause::new( + terminator.source_info.span, + hir_id, + ObligationCauseCode::ItemObligation(callee), ); - - for p in normalized.obligations { - fulfill_cx.register_predicate_obligation(&infcx, p); - } - for obligation in traits::predicates_for_generics( - |_, _| cause(), + let normalized_predicates = ocx.normalize(&cause, param_env, predicates); + ocx.register_obligations(traits::predicates_for_generics( + |_, _| cause.clone(), self.param_env, - normalized.value, - ) { - fulfill_cx.register_predicate_obligation(&infcx, obligation); - } - let errors = fulfill_cx.select_all_or_error(&infcx); + normalized_predicates, + )); + + let errors = ocx.select_all_or_error(); if !errors.is_empty() { - infcx.err_ctxt().report_fulfillment_errors(&errors, None, false); + infcx.err_ctxt().report_fulfillment_errors(&errors, None); } } @@ -828,11 +821,10 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { if !nonconst_call_permission { let obligation = Obligation::new( + tcx, ObligationCause::dummy_with_span(*fn_span), param_env, - tcx.mk_predicate( - poly_trait_pred.map_bound(ty::PredicateKind::Trait), - ), + poly_trait_pred, ); // improve diagnostics by showing what failed. Our requirements are stricter this time @@ -843,7 +835,6 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { obligation.clone(), &obligation, &e, - false, ); } @@ -901,14 +892,6 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { return; } - // `async` blocks get lowered to `std::future::from_generator(/* a closure */)`. - let is_async_block = Some(callee) == tcx.lang_items().from_generator_fn(); - if is_async_block { - let kind = hir::GeneratorKind::Async(hir::AsyncGeneratorKind::Block); - self.check_op(ops::Generator(kind)); - return; - } - if !tcx.is_const_fn_raw(callee) { if !tcx.is_const_default_method(callee) { // To get to here we must have already found a const impl for the diff --git a/compiler/rustc_const_eval/src/transform/check_consts/mod.rs b/compiler/rustc_const_eval/src/transform/check_consts/mod.rs index 25b420bed..655ec345e 100644 --- a/compiler/rustc_const_eval/src/transform/check_consts/mod.rs +++ b/compiler/rustc_const_eval/src/transform/check_consts/mod.rs @@ -62,7 +62,7 @@ impl<'mir, 'tcx> ConstCx<'mir, 'tcx> { } fn is_async(&self) -> bool { - self.tcx.asyncness(self.def_id()) == hir::IsAsync::Async + self.tcx.asyncness(self.def_id()).is_async() } } @@ -75,14 +75,14 @@ pub fn rustc_allow_const_fn_unstable( attr::rustc_allow_const_fn_unstable(&tcx.sess, attrs).any(|name| name == feature_gate) } -// Returns `true` if the given `const fn` is "const-stable". -// -// Panics if the given `DefId` does not refer to a `const fn`. -// -// Const-stability is only relevant for `const fn` within a `staged_api` crate. Only "const-stable" -// functions can be called in a const-context by users of the stable compiler. "const-stable" -// functions are subject to more stringent restrictions than "const-unstable" functions: They -// cannot use unstable features and can only call other "const-stable" functions. +/// Returns `true` if the given `const fn` is "const-stable". +/// +/// Panics if the given `DefId` does not refer to a `const fn`. +/// +/// Const-stability is only relevant for `const fn` within a `staged_api` crate. Only "const-stable" +/// functions can be called in a const-context by users of the stable compiler. "const-stable" +/// functions are subject to more stringent restrictions than "const-unstable" functions: They +/// cannot use unstable features and can only call other "const-stable" functions. pub fn is_const_stable_const_fn(tcx: TyCtxt<'_>, def_id: DefId) -> bool { // A default body in a `#[const_trait]` is not const-stable because const // trait fns currently cannot be const-stable. We shouldn't diff --git a/compiler/rustc_const_eval/src/transform/check_consts/ops.rs b/compiler/rustc_const_eval/src/transform/check_consts/ops.rs index b28d70194..b19d270e6 100644 --- a/compiler/rustc_const_eval/src/transform/check_consts/ops.rs +++ b/compiler/rustc_const_eval/src/transform/check_consts/ops.rs @@ -1,7 +1,7 @@ //! Concrete error types for all operations which may be invalid in a certain const context. use hir::def_id::LocalDefId; -use hir::ConstContext; +use hir::{ConstContext, LangItem}; use rustc_errors::{ error_code, struct_span_err, Applicability, DiagnosticBuilder, ErrorGuaranteed, }; @@ -13,10 +13,9 @@ use rustc_middle::mir; use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::subst::{GenericArgKind, SubstsRef}; use rustc_middle::ty::{ - suggest_constraining_type_param, Adt, Closure, DefIdTree, FnDef, FnPtr, Param, TraitPredicate, - Ty, + suggest_constraining_type_param, Adt, Closure, DefIdTree, FnDef, FnPtr, Param, Ty, }; -use rustc_middle::ty::{Binder, BoundConstness, ImplPolarity, TraitRef}; +use rustc_middle::ty::{Binder, TraitRef}; use rustc_session::parse::feature_err; use rustc_span::symbol::sym; use rustc_span::{BytePos, Pos, Span, Symbol}; @@ -147,13 +146,10 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { } Adt(..) => { let obligation = Obligation::new( + tcx, ObligationCause::dummy(), param_env, - Binder::dummy(TraitPredicate { - trait_ref, - constness: BoundConstness::NotConst, - polarity: ImplPolarity::Positive, - }), + Binder::dummy(trait_ref), ); let infcx = tcx.infer_ctxt().build(); @@ -303,7 +299,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { err.span_note(deref_target, "deref defined here"); } - diag_trait(&mut err, self_ty, tcx.lang_items().deref_trait().unwrap()); + diag_trait(&mut err, self_ty, tcx.require_lang_item(LangItem::Deref, Some(span))); err } _ if tcx.opt_parent(callee) == tcx.get_diagnostic_item(sym::ArgumentV1Methods) => { @@ -380,7 +376,7 @@ impl<'tcx> NonConstOp<'tcx> for Generator { ccx: &ConstCx<'_, 'tcx>, span: Span, ) -> DiagnosticBuilder<'tcx, ErrorGuaranteed> { - let msg = format!("{}s are not allowed in {}s", self.0, ccx.const_kind()); + let msg = format!("{}s are not allowed in {}s", self.0.descr(), ccx.const_kind()); if let hir::GeneratorKind::Async(hir::AsyncGeneratorKind::Block) = self.0 { ccx.tcx.sess.create_feature_err( UnallowedOpInConstContext { span, msg }, @@ -690,7 +686,7 @@ impl<'tcx> NonConstOp<'tcx> for ThreadLocalAccess { } } -// Types that cannot appear in the signature or locals of a `const fn`. +/// Types that cannot appear in the signature or locals of a `const fn`. pub mod ty { use super::*; diff --git a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs index 335992342..8ca3fdf40 100644 --- a/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs +++ b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs @@ -146,25 +146,19 @@ impl Qualif for NeedsNonConstDrop { qualifs.needs_non_const_drop } + #[instrument(level = "trace", skip(cx), ret)] fn in_any_value_of_ty<'tcx>(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool { // Avoid selecting for simple cases, such as builtin types. if ty::util::is_trivially_const_drop(ty) { return false; } - let destruct = cx.tcx.require_lang_item(LangItem::Destruct, None); - let obligation = Obligation::new( - ObligationCause::dummy(), + cx.tcx, + ObligationCause::dummy_with_span(cx.body.span), cx.param_env, - ty::Binder::dummy(ty::TraitPredicate { - trait_ref: ty::TraitRef { - def_id: destruct, - substs: cx.tcx.mk_substs_trait(ty, &[]), - }, - constness: ty::BoundConstness::ConstIfConst, - polarity: ty::ImplPolarity::Positive, - }), + ty::Binder::dummy(cx.tcx.at(cx.body.span).mk_trait_ref(LangItem::Destruct, [ty])) + .with_constness(ty::BoundConstness::ConstIfConst), ); let infcx = cx.tcx.infer_ctxt().build(); @@ -174,6 +168,8 @@ impl Qualif for NeedsNonConstDrop { return true; }; + trace!(?impl_src); + if !matches!( impl_src, ImplSource::ConstDestruct(_) | ImplSource::Param(_, ty::BoundConstness::ConstIfConst) @@ -348,7 +344,11 @@ where // FIXME(valtrees): check whether const qualifs should behave the same // way for type and mir constants. let uneval = match constant.literal { - ConstantKind::Ty(ct) if matches!(ct.kind(), ty::ConstKind::Param(_)) => None, + ConstantKind::Ty(ct) + if matches!(ct.kind(), ty::ConstKind::Param(_) | ty::ConstKind::Error(_)) => + { + None + } ConstantKind::Ty(c) => bug!("expected ConstKind::Param here, found {:?}", c), ConstantKind::Unevaluated(uv, _) => Some(uv), ConstantKind::Val(..) => None, |