diff options
Diffstat (limited to 'compiler/rustc_const_eval/src')
37 files changed, 854 insertions, 778 deletions
diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs index aea3d5bd3e7..f4257ad9671 100644 --- a/compiler/rustc_const_eval/src/check_consts/check.rs +++ b/compiler/rustc_const_eval/src/check_consts/check.rs @@ -3,9 +3,10 @@ use std::assert_matches::assert_matches; use std::borrow::Cow; use std::mem; +use std::num::NonZero; use std::ops::Deref; -use rustc_attr::{ConstStability, StabilityLevel}; +use rustc_attr_parsing::{ConstStability, StabilityLevel}; use rustc_errors::{Diag, ErrorGuaranteed}; use rustc_hir::def_id::DefId; use rustc_hir::{self as hir, LangItem}; @@ -15,15 +16,14 @@ use rustc_middle::mir::visit::Visitor; use rustc_middle::mir::*; use rustc_middle::span_bug; use rustc_middle::ty::adjustment::PointerCoercion; -use rustc_middle::ty::{self, Instance, InstanceKind, Ty, TypeVisitableExt}; +use rustc_middle::ty::{self, Ty, TypeVisitableExt}; use rustc_mir_dataflow::Analysis; -use rustc_mir_dataflow::impls::MaybeStorageLive; -use rustc_mir_dataflow::storage::always_storage_live_locals; +use rustc_mir_dataflow::impls::{MaybeStorageLive, always_storage_live_locals}; use rustc_span::{Span, Symbol, sym}; use rustc_trait_selection::traits::{ Obligation, ObligationCause, ObligationCauseCode, ObligationCtxt, }; -use tracing::{debug, instrument, trace}; +use tracing::{instrument, trace}; use super::ops::{self, NonConstOp, Status}; use super::qualifs::{self, HasMutInterior, NeedsDrop, NeedsNonConstDrop}; @@ -46,7 +46,7 @@ impl<'mir, 'tcx> Qualifs<'mir, 'tcx> { /// Returns `true` if `local` is `NeedsDrop` at the given `Location`. /// /// Only updates the cursor if absolutely necessary - fn needs_drop( + pub(crate) fn needs_drop( &mut self, ccx: &'mir ConstCx<'mir, 'tcx>, local: Local, @@ -271,9 +271,18 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { /// context. pub fn check_op_spanned<O: NonConstOp<'tcx>>(&mut self, op: O, span: Span) { let gate = match op.status_in_item(self.ccx) { - Status::Unstable { gate, safe_to_expose_on_stable, is_function_call } - if self.tcx.features().enabled(gate) => - { + Status::Unstable { + gate, + safe_to_expose_on_stable, + is_function_call, + gate_already_checked, + } if gate_already_checked || self.tcx.features().enabled(gate) => { + if gate_already_checked { + assert!( + !safe_to_expose_on_stable, + "setting `gate_already_checked` without `safe_to_expose_on_stable` makes no sense" + ); + } // Generally this is allowed since the feature gate is enabled -- except // if this function wants to be safe-to-expose-on-stable. if !safe_to_expose_on_stable @@ -361,34 +370,24 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { !is_transient } + /// Returns whether there are const-conditions. fn revalidate_conditional_constness( &mut self, callee: DefId, callee_args: ty::GenericArgsRef<'tcx>, - call_source: CallSource, call_span: Span, - ) { + ) -> bool { let tcx = self.tcx; if !tcx.is_conditionally_const(callee) { - return; + return false; } let const_conditions = tcx.const_conditions(callee).instantiate(tcx, callee_args); - // If there are any const conditions on this fn and `const_trait_impl` - // is not enabled, simply bail. We shouldn't be able to call conditionally - // const functions on stable. - if !const_conditions.is_empty() && !tcx.features().const_trait_impl() { - self.check_op(ops::FnCallNonConst { - callee, - args: callee_args, - span: call_span, - call_source, - feature: Some(sym::const_trait_impl), - }); - return; + if const_conditions.is_empty() { + return false; } - let infcx = tcx.infer_ctxt().build(self.body.typing_mode(tcx)); + let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(self.body.typing_env(tcx)); let ocx = ObligationCtxt::new_with_diagnostics(&infcx); let body_id = self.body.source.def_id().expect_local(); @@ -398,11 +397,8 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { ty::BoundConstness::Const } }; - let const_conditions = ocx.normalize( - &ObligationCause::misc(call_span, body_id), - self.param_env, - const_conditions, - ); + let const_conditions = + ocx.normalize(&ObligationCause::misc(call_span, body_id), param_env, const_conditions); ocx.register_obligations(const_conditions.into_iter().map(|(trait_ref, span)| { Obligation::new( tcx, @@ -411,7 +407,7 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { body_id, ObligationCauseCode::WhereClause(callee, span), ), - self.param_env, + param_env, trait_ref.to_host_effect_clause(tcx, host_polarity), ) })); @@ -421,6 +417,45 @@ impl<'mir, 'tcx> Checker<'mir, 'tcx> { tcx.dcx() .span_delayed_bug(call_span, "this should have reported a ~const error in HIR"); } + + true + } + + pub fn check_drop_terminator( + &mut self, + dropped_place: Place<'tcx>, + location: Location, + terminator_span: Span, + ) { + let ty_of_dropped_place = dropped_place.ty(self.body, self.tcx).ty; + + let needs_drop = if let Some(local) = dropped_place.as_local() { + self.qualifs.needs_drop(self.ccx, local, location) + } else { + qualifs::NeedsDrop::in_any_value_of_ty(self.ccx, ty_of_dropped_place) + }; + // If this type doesn't need a drop at all, then there's nothing to enforce. + if !needs_drop { + return; + } + + let mut err_span = self.span; + let needs_non_const_drop = if let Some(local) = dropped_place.as_local() { + // Use the span where the local was declared as the span of the drop error. + err_span = self.body.local_decls[local].source_info.span; + self.qualifs.needs_non_const_drop(self.ccx, local, location) + } else { + qualifs::NeedsNonConstDrop::in_any_value_of_ty(self.ccx, ty_of_dropped_place) + }; + + self.check_op_spanned( + ops::LiveDrop { + dropped_at: terminator_span, + dropped_ty: ty_of_dropped_place, + needs_non_const_drop, + }, + err_span, + ); } } @@ -538,12 +573,27 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { ) => {} Rvalue::ShallowInitBox(_, _) => {} - Rvalue::UnaryOp(_, operand) => { + Rvalue::UnaryOp(op, operand) => { let ty = operand.ty(self.body, self.tcx); - if is_int_bool_float_or_char(ty) { - // Int, bool, float, and char operations are fine. - } else { - span_bug!(self.span, "non-primitive type in `Rvalue::UnaryOp`: {:?}", ty); + match op { + UnOp::Not | UnOp::Neg => { + if is_int_bool_float_or_char(ty) { + // Int, bool, float, and char operations are fine. + } else { + span_bug!( + self.span, + "non-primitive type in `Rvalue::UnaryOp{op:?}`: {ty:?}", + ); + } + } + UnOp::PtrMetadata => { + if !ty.is_ref() && !ty.is_unsafe_ptr() { + span_bug!( + self.span, + "non-pointer type in `Rvalue::UnaryOp({op:?})`: {ty:?}", + ); + } + } } } @@ -610,6 +660,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { | StatementKind::Coverage(..) | StatementKind::Intrinsic(..) | StatementKind::ConstEvalCounter + | StatementKind::BackwardIncompatibleDropHint { .. } | StatementKind::Nop => {} } } @@ -627,11 +678,11 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { _ => unreachable!(), }; - let ConstCx { tcx, body, param_env, .. } = *self.ccx; + let ConstCx { tcx, body, .. } = *self.ccx; let fn_ty = func.ty(body, tcx); - let (mut callee, mut fn_args) = match *fn_ty.kind() { + let (callee, fn_args) = match *fn_ty.kind() { ty::FnDef(def_id, fn_args) => (def_id, fn_args), ty::FnPtr(..) => { @@ -645,57 +696,38 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } }; - self.revalidate_conditional_constness(callee, fn_args, call_source, *fn_span); + let has_const_conditions = + self.revalidate_conditional_constness(callee, fn_args, *fn_span); - let mut is_trait = false; // Attempting to call a trait method? if let Some(trait_did) = tcx.trait_of_item(callee) { - trace!("attempting to call a trait method"); + // We can't determine the actual callee here, so we have to do different checks + // than usual. + trace!("attempting to call a trait method"); let trait_is_const = tcx.is_const_trait(trait_did); - // trait method calls are only permitted when `effects` is enabled. - // typeck ensures the conditions for calling a const trait method are met, - // so we only error if the trait isn't const. We try to resolve the trait - // into the concrete method, and uses that for const stability checks. - // FIXME(const_trait_impl) we might consider moving const stability checks - // to typeck as well. - if tcx.features().const_trait_impl() && trait_is_const { - // This skips the check below that ensures we only call `const fn`. - is_trait = true; - - if let Ok(Some(instance)) = - Instance::try_resolve(tcx, param_env, callee, fn_args) - && let InstanceKind::Item(def) = instance.def - { - // Resolve a trait method call to its concrete implementation, which may be in a - // `const` trait impl. This is only used for the const stability check below, since - // we want to look at the concrete impl's stability. - fn_args = instance.args; - callee = def; - } + + if trait_is_const { + // Trait calls are always conditionally-const. + self.check_op(ops::ConditionallyConstCall { callee, args: fn_args }); + // FIXME(const_trait_impl): do a more fine-grained check whether this + // particular trait can be const-stably called. } else { - // if the trait is const but the user has not enabled the feature(s), - // suggest them. - let feature = if trait_is_const { - Some(if tcx.features().const_trait_impl() { - sym::effects - } else { - sym::const_trait_impl - }) - } else { - None - }; + // Not even a const trait. self.check_op(ops::FnCallNonConst { callee, args: fn_args, span: *fn_span, call_source, - feature, }); - // If we allowed this, we're in miri-unleashed mode, so we might - // as well skip the remaining checks. - return; } + // That's all we can check here. + return; + } + + // Even if we know the callee, ensure we can use conditionally-const calls. + if has_const_conditions { + self.check_op(ops::ConditionallyConstCall { callee, args: fn_args }); } // At this point, we are calling a function, `callee`, whose `DefId` is known... @@ -736,6 +768,13 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // Intrinsics are language primitives, not regular calls, so treat them separately. if let Some(intrinsic) = tcx.intrinsic(callee) { + if !tcx.is_const_fn(callee) { + // Non-const intrinsic. + self.check_op(ops::IntrinsicNonConst { name: intrinsic.name }); + // If we allowed this, we're in miri-unleashed mode, so we might + // as well skip the remaining checks. + return; + } // We use `intrinsic.const_stable` to determine if this can be safely exposed to // stable code, rather than `const_stable_indirect`. This is to make // `#[rustc_const_stable_indirect]` an attribute that is always safe to add. @@ -743,17 +782,12 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // fallback body is safe to expose on stable. let is_const_stable = intrinsic.const_stable || (!intrinsic.must_be_overridden - && tcx.is_const_fn(callee) && is_safe_to_expose_on_stable_const_fn(tcx, callee)); match tcx.lookup_const_stability(callee) { None => { - // Non-const intrinsic. - self.check_op(ops::IntrinsicNonConst { name: intrinsic.name }); - } - Some(ConstStability { feature: None, .. }) => { - // Intrinsic does not need a separate feature gate (we rely on the - // regular stability checker). However, we have to worry about recursive - // const stability. + // This doesn't need a separate const-stability check -- const-stability equals + // regular stability, and regular stability is checked separately. + // However, we *do* have to worry about *recursive* const stability. if !is_const_stable && self.enforce_recursive_const_stability() { self.dcx().emit_err(errors::UnmarkedIntrinsicExposed { span: self.span, @@ -762,20 +796,20 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } } Some(ConstStability { - feature: Some(feature), level: StabilityLevel::Unstable { .. }, + feature, .. }) => { self.check_op(ops::IntrinsicUnstable { name: intrinsic.name, feature, - const_stable: is_const_stable, + const_stable_indirect: is_const_stable, }); } Some(ConstStability { level: StabilityLevel::Stable { .. }, .. }) => { // All good. Note that a `#[rustc_const_stable]` intrinsic (meaning it // can be *directly* invoked from stable const code) does not always - // have the `#[rustc_const_stable_intrinsic]` attribute (which controls + // have the `#[rustc_intrinsic_const_stable_indirect]` attribute (which controls // exposing an intrinsic indirectly); we accept this call anyway. } } @@ -783,14 +817,12 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { return; } - // Trait functions are not `const fn` so we have to skip them here. - if !tcx.is_const_fn(callee) && !is_trait { + if !tcx.is_const_fn(callee) { self.check_op(ops::FnCallNonConst { callee, args: fn_args, span: *fn_span, call_source, - feature: None, }); // If we allowed this, we're in miri-unleashed mode, so we might // as well skip the remaining checks. @@ -802,7 +834,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { Some(ConstStability { level: StabilityLevel::Stable { .. }, .. }) => { // All good. } - None | Some(ConstStability { feature: None, .. }) => { + None => { // This doesn't need a separate const-stability check -- const-stability equals // regular stability, and regular stability is checked separately. // However, we *do* have to worry about *recursive* const stability. @@ -816,8 +848,8 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { } } Some(ConstStability { - feature: Some(feature), - level: StabilityLevel::Unstable { implied_by: implied_feature, .. }, + level: StabilityLevel::Unstable { implied_by: implied_feature, issue, .. }, + feature, .. }) => { // An unstable const fn with a feature gate. @@ -826,6 +858,12 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // We only honor `span.allows_unstable` aka `#[allow_internal_unstable]` if // the callee is safe to expose, to avoid bypassing recursive stability. + // This is not ideal since it means the user sees an error, not the macro + // author, but that's also the case if one forgets to set + // `#[allow_internal_unstable]` in the first place. Note that this cannot be + // integrated in the check below since we want to enforce + // `callee_safe_to_expose_on_stable` even if + // `!self.enforce_recursive_const_stability()`. if (self.span.allows_unstable(feature) || implied_feature.is_some_and(|f| self.span.allows_unstable(f))) && callee_safe_to_expose_on_stable @@ -839,16 +877,30 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { // to allow this. let feature_enabled = callee.is_local() || tcx.features().enabled(feature) - || implied_feature.is_some_and(|f| tcx.features().enabled(f)); - // We do *not* honor this if we are in the "danger zone": we have to enforce - // recursive const-stability and the callee is not safe-to-expose. In that - // case we need `check_op` to do the check. - let danger_zone = !callee_safe_to_expose_on_stable - && self.enforce_recursive_const_stability(); - if danger_zone || !feature_enabled { + || implied_feature.is_some_and(|f| tcx.features().enabled(f)) + || { + // When we're compiling the compiler itself we may pull in + // crates from crates.io, but those crates may depend on other + // crates also pulled in from crates.io. We want to ideally be + // able to compile everything without requiring upstream + // modifications, so in the case that this looks like a + // `rustc_private` crate (e.g., a compiler crate) and we also have + // the `-Z force-unstable-if-unmarked` flag present (we're + // compiling a compiler crate), then let this missing feature + // annotation slide. + // This matches what we do in `eval_stability_allow_unstable` for + // regular stability. + feature == sym::rustc_private + && issue == NonZero::new(27812) + && self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked + }; + // Even if the feature is enabled, we still need check_op to double-check + // this if the callee is not safe to expose on stable. + if !feature_enabled || !callee_safe_to_expose_on_stable { self.check_op(ops::FnCallUnstable { def_id: callee, feature, + feature_enabled, safe_to_expose_on_stable: callee_safe_to_expose_on_stable, }); } @@ -865,35 +917,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> { return; } - let mut err_span = self.span; - let ty_of_dropped_place = dropped_place.ty(self.body, self.tcx).ty; - - let ty_needs_non_const_drop = - qualifs::NeedsNonConstDrop::in_any_value_of_ty(self.ccx, ty_of_dropped_place); - - debug!(?ty_of_dropped_place, ?ty_needs_non_const_drop); - - if !ty_needs_non_const_drop { - return; - } - - let needs_non_const_drop = if let Some(local) = dropped_place.as_local() { - // Use the span where the local was declared as the span of the drop error. - err_span = self.body.local_decls[local].source_info.span; - self.qualifs.needs_non_const_drop(self.ccx, local, location) - } else { - true - }; - - if needs_non_const_drop { - self.check_op_spanned( - ops::LiveDrop { - dropped_at: Some(terminator.source_info.span), - dropped_ty: ty_of_dropped_place, - }, - err_span, - ); - } + self.check_drop_terminator(*dropped_place, location, terminator.source_info.span); } TerminatorKind::InlineAsm { .. } => self.check_op(ops::InlineAsm), diff --git a/compiler/rustc_const_eval/src/check_consts/mod.rs b/compiler/rustc_const_eval/src/check_consts/mod.rs index dcdaafaecc2..ab68691f1b9 100644 --- a/compiler/rustc_const_eval/src/check_consts/mod.rs +++ b/compiler/rustc_const_eval/src/check_consts/mod.rs @@ -9,7 +9,7 @@ use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::ty::{self, PolyFnSig, TyCtxt}; use rustc_middle::{bug, mir}; use rustc_span::Symbol; -use {rustc_attr as attr, rustc_hir as hir}; +use {rustc_attr_parsing as attr, rustc_hir as hir}; pub use self::qualifs::Qualif; @@ -24,17 +24,15 @@ mod resolver; pub struct ConstCx<'mir, 'tcx> { pub body: &'mir mir::Body<'tcx>, pub tcx: TyCtxt<'tcx>, - pub param_env: ty::ParamEnv<'tcx>, + pub typing_env: ty::TypingEnv<'tcx>, pub const_kind: Option<hir::ConstContext>, } impl<'mir, 'tcx> ConstCx<'mir, 'tcx> { pub fn new(tcx: TyCtxt<'tcx>, body: &'mir mir::Body<'tcx>) -> Self { - let def_id = body.source.def_id().expect_local(); - let param_env = tcx.param_env(def_id); - + let typing_env = body.typing_env(tcx); let const_kind = tcx.hir().body_const_context(body.source.def_id().expect_local()); - ConstCx { body, tcx, param_env, const_kind } + ConstCx { body, tcx, typing_env, const_kind } } pub(crate) fn dcx(&self) -> DiagCtxtHandle<'tcx> { @@ -53,10 +51,11 @@ impl<'mir, 'tcx> ConstCx<'mir, 'tcx> { } pub fn enforce_recursive_const_stability(&self) -> bool { - // We can skip this if `staged_api` is not enabled, since in such crates - // `lookup_const_stability` will always be `None`. + // We can skip this if neither `staged_api` nor `-Zforce-unstable-if-unmarked` are enabled, + // since in such crates `lookup_const_stability` will always be `None`. self.const_kind == Some(hir::ConstContext::ConstFn) - && self.tcx.features().staged_api() + && (self.tcx.features().staged_api() + || self.tcx.sess.opts.unstable_opts.force_unstable_if_unmarked) && is_safe_to_expose_on_stable_const_fn(self.tcx, self.def_id().to_def_id()) } @@ -109,14 +108,15 @@ pub fn is_safe_to_expose_on_stable_const_fn(tcx: TyCtxt<'_>, def_id: DefId) -> b match tcx.lookup_const_stability(def_id) { None => { - // Only marked functions can be trusted. Note that this may be a function in a - // non-staged-API crate where no recursive checks were done! - false + // In a `staged_api` crate, we do enforce recursive const stability for all unmarked + // functions, so we can trust local functions. But in another crate we don't know which + // rules were applied, so we can't trust that. + def_id.is_local() && tcx.features().staged_api() } Some(stab) => { - // We consider things safe-to-expose if they are stable, if they don't have any explicit - // const stability attribute, or if they are marked as `const_stable_indirect`. - stab.is_const_stable() || stab.feature.is_none() || stab.const_stable_indirect + // We consider things safe-to-expose if they are stable or if they are marked as + // `const_stable_indirect`. + stab.is_const_stable() || stab.const_stable_indirect } } } diff --git a/compiler/rustc_const_eval/src/check_consts/ops.rs b/compiler/rustc_const_eval/src/check_consts/ops.rs index 2931159842f..afb7900c4b0 100644 --- a/compiler/rustc_const_eval/src/check_consts/ops.rs +++ b/compiler/rustc_const_eval/src/check_consts/ops.rs @@ -15,8 +15,7 @@ use rustc_middle::ty::{ suggest_constraining_type_param, }; use rustc_middle::util::{CallDesugaringKind, CallKind, call_kind}; -use rustc_span::symbol::sym; -use rustc_span::{BytePos, Pos, Span, Symbol}; +use rustc_span::{BytePos, Pos, Span, Symbol, sym}; use rustc_trait_selection::traits::SelectionContext; use tracing::debug; @@ -28,6 +27,9 @@ pub enum Status { Unstable { /// The feature that must be enabled to use this operation. gate: Symbol, + /// Whether the feature gate was already checked (because the logic is a bit more + /// complicated than just checking a single gate). + gate_already_checked: bool, /// Whether it is allowed to use this operation from stable `const fn`. /// This will usually be `false`. safe_to_expose_on_stable: bool, @@ -70,6 +72,38 @@ impl<'tcx> NonConstOp<'tcx> for FnCallIndirect { } } +/// A call to a function that is in a trait, or has trait bounds that make it conditionally-const. +#[derive(Debug)] +pub(crate) struct ConditionallyConstCall<'tcx> { + pub callee: DefId, + pub args: GenericArgsRef<'tcx>, +} + +impl<'tcx> NonConstOp<'tcx> for ConditionallyConstCall<'tcx> { + fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { + // We use the `const_trait_impl` gate for all conditionally-const calls. + Status::Unstable { + gate: sym::const_trait_impl, + gate_already_checked: false, + safe_to_expose_on_stable: false, + // We don't want the "mark the callee as `#[rustc_const_stable_indirect]`" hint + is_function_call: false, + } + } + + fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { + ccx.tcx.sess.create_feature_err( + errors::ConditionallyConstCall { + span, + def_path_str: ccx.tcx.def_path_str_with_args(self.callee, self.args), + def_descr: ccx.tcx.def_descr(self.callee), + kind: ccx.const_kind(), + }, + sym::const_trait_impl, + ) + } +} + /// A function call where the callee is not marked as `const`. #[derive(Debug, Clone, Copy)] pub(crate) struct FnCallNonConst<'tcx> { @@ -77,7 +111,6 @@ pub(crate) struct FnCallNonConst<'tcx> { pub args: GenericArgsRef<'tcx>, pub span: Span, pub call_source: CallSource, - pub feature: Option<Symbol>, } impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { @@ -85,8 +118,8 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { #[allow(rustc::diagnostic_outside_of_impl)] #[allow(rustc::untranslatable_diagnostic)] fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, _: Span) -> Diag<'tcx> { - let FnCallNonConst { callee, args, span, call_source, feature } = *self; - let ConstCx { tcx, param_env, .. } = *ccx; + let FnCallNonConst { callee, args, span, call_source } = *self; + let ConstCx { tcx, typing_env, .. } = *ccx; let caller = ccx.def_id(); let diag_trait = |err, self_ty: Ty<'_>, trait_id| { @@ -106,19 +139,17 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { err, param_ty.name.as_str(), &constraint, - None, + Some(trait_ref.def_id), None, ); } } ty::Adt(..) => { + let (infcx, param_env) = tcx.infer_ctxt().build_with_typing_env(typing_env); let obligation = Obligation::new(tcx, ObligationCause::dummy(), param_env, trait_ref); - - let infcx = tcx.infer_ctxt().build(ccx.body.typing_mode(tcx)); let mut selcx = SelectionContext::new(&infcx); let implsrc = selcx.select(&obligation); - if let Ok(Some(ImplSource::UserDefined(data))) = implsrc { // FIXME(const_trait_impl) revisit this if !tcx.is_const_trait_impl(data.impl_def_id) { @@ -132,7 +163,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { }; let call_kind = - call_kind(tcx, ccx.param_env, callee, args, span, call_source.from_hir_call(), None); + call_kind(tcx, ccx.typing_env, callee, args, span, call_source.from_hir_call(), None); debug!(?call_kind); @@ -148,8 +179,10 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { }; } - let mut err = match kind { - CallDesugaringKind::ForLoopIntoIter => { + // Don't point at the trait if this is a desugaring... + // FIXME(const_trait_impl): we could perhaps do this for `Iterator`. + match kind { + CallDesugaringKind::ForLoopIntoIter | CallDesugaringKind::ForLoopNext => { error!(NonConstForLoopIntoIter) } CallDesugaringKind::QuestionBranch => { @@ -164,10 +197,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { CallDesugaringKind::Await => { error!(NonConstAwait) } - }; - - diag_trait(&mut err, self_ty, kind.trait_def_id(tcx)); - err + } } CallKind::FnCall { fn_trait_id, self_ty } => { let note = match self_ty.kind() { @@ -285,14 +315,6 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { ccx.const_kind(), )); - if let Some(feature) = feature { - ccx.tcx.disabled_nightly_features( - &mut err, - Some(ccx.tcx.local_def_id_to_hir_id(caller)), - [(String::new(), feature)], - ); - } - if let ConstContext::Static(_) = ccx.const_kind() { err.note(fluent_generated::const_eval_lazy_lock); } @@ -308,6 +330,9 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { pub(crate) struct FnCallUnstable { pub def_id: DefId, pub feature: Symbol, + /// If this is true, then the feature is enabled, but we need to still check if it is safe to + /// expose on stable. + pub feature_enabled: bool, pub safe_to_expose_on_stable: bool, } @@ -315,12 +340,14 @@ impl<'tcx> NonConstOp<'tcx> for FnCallUnstable { fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { Status::Unstable { gate: self.feature, + gate_already_checked: self.feature_enabled, safe_to_expose_on_stable: self.safe_to_expose_on_stable, is_function_call: true, } } fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { + assert!(!self.feature_enabled); let mut err = ccx.dcx().create_err(errors::UnstableConstFn { span, def_path: ccx.tcx.def_path_str(self.def_id), @@ -354,14 +381,15 @@ impl<'tcx> NonConstOp<'tcx> for IntrinsicNonConst { pub(crate) struct IntrinsicUnstable { pub name: Symbol, pub feature: Symbol, - pub const_stable: bool, + pub const_stable_indirect: bool, } impl<'tcx> NonConstOp<'tcx> for IntrinsicUnstable { fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { Status::Unstable { gate: self.feature, - safe_to_expose_on_stable: self.const_stable, + gate_already_checked: false, + safe_to_expose_on_stable: self.const_stable_indirect, // We do *not* want to suggest to mark the intrinsic as `const_stable_indirect`, // that's not a trivial change! is_function_call: false, @@ -388,6 +416,7 @@ impl<'tcx> NonConstOp<'tcx> for Coroutine { { Status::Unstable { gate: sym::const_async_blocks, + gate_already_checked: false, safe_to_expose_on_stable: false, is_function_call: false, } @@ -398,15 +427,8 @@ impl<'tcx> NonConstOp<'tcx> for Coroutine { fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { let msg = format!("{:#}s are not allowed in {}s", self.0, ccx.const_kind()); - if let hir::CoroutineKind::Desugared( - hir::CoroutineDesugaring::Async, - hir::CoroutineSource::Block, - ) = self.0 - { - ccx.tcx.sess.create_feature_err( - errors::UnallowedOpInConstContext { span, msg }, - sym::const_async_blocks, - ) + if let Status::Unstable { gate, .. } = self.status_in_item(ccx) { + ccx.tcx.sess.create_feature_err(errors::UnallowedOpInConstContext { span, msg }, gate) } else { ccx.dcx().create_err(errors::UnallowedOpInConstContext { span, msg }) } @@ -435,17 +457,43 @@ impl<'tcx> NonConstOp<'tcx> for InlineAsm { #[derive(Debug)] pub(crate) struct LiveDrop<'tcx> { - pub dropped_at: Option<Span>, + pub dropped_at: Span, pub dropped_ty: Ty<'tcx>, + pub needs_non_const_drop: bool, } impl<'tcx> NonConstOp<'tcx> for LiveDrop<'tcx> { + fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { + if self.needs_non_const_drop { + Status::Forbidden + } else { + Status::Unstable { + gate: sym::const_destruct, + gate_already_checked: false, + safe_to_expose_on_stable: false, + is_function_call: false, + } + } + } + fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { - ccx.dcx().create_err(errors::LiveDrop { - span, - dropped_ty: self.dropped_ty, - kind: ccx.const_kind(), - dropped_at: self.dropped_at, - }) + if self.needs_non_const_drop { + ccx.dcx().create_err(errors::LiveDrop { + span, + dropped_ty: self.dropped_ty, + kind: ccx.const_kind(), + dropped_at: self.dropped_at, + }) + } else { + ccx.tcx.sess.create_feature_err( + errors::LiveDrop { + span, + dropped_ty: self.dropped_ty, + kind: ccx.const_kind(), + dropped_at: self.dropped_at, + }, + sym::const_destruct, + ) + } } } diff --git a/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs b/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs index 0173a528c22..16e142a85ee 100644 --- a/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs +++ b/compiler/rustc_const_eval/src/check_consts/post_drop_elaboration.rs @@ -1,14 +1,11 @@ use rustc_middle::mir::visit::Visitor; use rustc_middle::mir::{self, BasicBlock, Location}; -use rustc_middle::ty::{Ty, TyCtxt}; -use rustc_span::Span; -use rustc_span::symbol::sym; +use rustc_middle::ty::TyCtxt; +use rustc_span::sym; use tracing::trace; use super::ConstCx; -use super::check::Qualifs; -use super::ops::{self, NonConstOp}; -use super::qualifs::{NeedsNonConstDrop, Qualif}; +use crate::check_consts::check::Checker; use crate::check_consts::rustc_allow_const_fn_unstable; /// Returns `true` if we should use the more precise live drop checker that runs after drop @@ -32,44 +29,29 @@ pub fn checking_enabled(ccx: &ConstCx<'_, '_>) -> bool { /// This is separate from the rest of the const checking logic because it must run after drop /// elaboration. pub fn check_live_drops<'tcx>(tcx: TyCtxt<'tcx>, body: &mir::Body<'tcx>) { - let def_id = body.source.def_id().expect_local(); - let const_kind = tcx.hir().body_const_context(def_id); - if const_kind.is_none() { + let ccx = ConstCx::new(tcx, body); + if ccx.const_kind.is_none() { return; } - if tcx.has_attr(def_id, sym::rustc_do_not_const_check) { + if tcx.has_attr(body.source.def_id(), sym::rustc_do_not_const_check) { return; } - let ccx = ConstCx { body, tcx, const_kind, param_env: tcx.param_env(def_id) }; if !checking_enabled(&ccx) { return; } - let mut visitor = CheckLiveDrops { ccx: &ccx, qualifs: Qualifs::default() }; + // I know it's not great to be creating a new const checker, but I'd + // rather use it so we can deduplicate the error emitting logic that + // it contains. + let mut visitor = CheckLiveDrops { checker: Checker::new(&ccx) }; visitor.visit_body(body); } struct CheckLiveDrops<'mir, 'tcx> { - ccx: &'mir ConstCx<'mir, 'tcx>, - qualifs: Qualifs<'mir, 'tcx>, -} - -// So we can access `body` and `tcx`. -impl<'mir, 'tcx> std::ops::Deref for CheckLiveDrops<'mir, 'tcx> { - type Target = ConstCx<'mir, 'tcx>; - - fn deref(&self) -> &Self::Target { - self.ccx - } -} - -impl<'tcx> CheckLiveDrops<'_, 'tcx> { - fn check_live_drop(&self, span: Span, dropped_ty: Ty<'tcx>) { - ops::LiveDrop { dropped_at: None, dropped_ty }.build_error(self.ccx, span).emit(); - } + checker: Checker<'mir, 'tcx>, } impl<'tcx> Visitor<'tcx> for CheckLiveDrops<'_, 'tcx> { @@ -89,28 +71,11 @@ impl<'tcx> Visitor<'tcx> for CheckLiveDrops<'_, 'tcx> { match &terminator.kind { mir::TerminatorKind::Drop { place: dropped_place, .. } => { - let dropped_ty = dropped_place.ty(self.body, self.tcx).ty; - - if !NeedsNonConstDrop::in_any_value_of_ty(self.ccx, dropped_ty) { - // Instead of throwing a bug, we just return here. This is because we have to - // run custom `const Drop` impls. - return; - } - - if dropped_place.is_indirect() { - self.check_live_drop(terminator.source_info.span, dropped_ty); - return; - } - - // Drop elaboration is not precise enough to accept code like - // `tests/ui/consts/control-flow/drop-pass.rs`; e.g., when an `Option<Vec<T>>` is - // initialized with `None` and never changed, it still emits drop glue. - // Hence we additionally check the qualifs here to allow more code to pass. - if self.qualifs.needs_non_const_drop(self.ccx, dropped_place.local, location) { - // Use the span where the dropped local was declared for the error. - let span = self.body.local_decls[dropped_place.local].source_info.span; - self.check_live_drop(span, dropped_ty); - } + self.checker.check_drop_terminator( + *dropped_place, + location, + terminator.source_info.span, + ); } mir::TerminatorKind::UnwindTerminate(_) diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs index 29a08579175..e244b50a4b5 100644 --- a/compiler/rustc_const_eval/src/check_consts/qualifs.rs +++ b/compiler/rustc_const_eval/src/check_consts/qualifs.rs @@ -2,11 +2,14 @@ //! //! See the `Qualif` trait for more info. +// FIXME(const_trait_impl): This API should be really reworked. It's dangerously general for +// having basically only two use-cases that act in different ways. + use rustc_errors::ErrorGuaranteed; use rustc_hir::LangItem; use rustc_infer::infer::TyCtxtInferExt; use rustc_middle::mir::*; -use rustc_middle::ty::{self, AdtDef, GenericArgsRef, Ty}; +use rustc_middle::ty::{self, AdtDef, Ty}; use rustc_middle::{bug, mir}; use rustc_trait_selection::traits::{Obligation, ObligationCause, ObligationCtxt}; use tracing::instrument; @@ -59,26 +62,12 @@ pub trait Qualif { /// It also determines the `Qualif`s for primitive types. fn in_any_value_of_ty<'tcx>(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool; - /// Returns `true` if this `Qualif` is inherent to the given struct or enum. - /// - /// By default, `Qualif`s propagate into ADTs in a structural way: An ADT only becomes - /// qualified if part of it is assigned a value with that `Qualif`. However, some ADTs *always* - /// have a certain `Qualif`, regardless of whether their fields have it. For example, a type - /// with a custom `Drop` impl is inherently `NeedsDrop`. - /// - /// Returning `true` for `in_adt_inherently` but `false` for `in_any_value_of_ty` is unsound. - fn in_adt_inherently<'tcx>( - cx: &ConstCx<'_, 'tcx>, - adt: AdtDef<'tcx>, - args: GenericArgsRef<'tcx>, - ) -> bool; - - /// Returns `true` if this `Qualif` behaves sructurally for pointers and references: - /// the pointer/reference qualifies if and only if the pointee qualifies. + /// Returns `true` if the `Qualif` is structural in an ADT's fields, i.e. if we may + /// recurse into an operand *value* to determine whether it has this `Qualif`. /// - /// (This is currently `false` for all our instances, but that may change in the future. Also, - /// by keeping it abstract, the handling of `Deref` in `in_place` becomes more clear.) - fn deref_structural<'tcx>(cx: &ConstCx<'_, 'tcx>) -> bool; + /// If this returns false, `in_any_value_of_ty` will be invoked to determine the + /// final qualif for this ADT. + fn is_structural_in_adt_value<'tcx>(cx: &ConstCx<'_, 'tcx>, adt: AdtDef<'tcx>) -> bool; } /// Constant containing interior mutability (`UnsafeCell<T>`). @@ -101,42 +90,43 @@ impl Qualif for HasMutInterior { return false; } + // Avoid selecting for `UnsafeCell` either. + if ty.ty_adt_def().is_some_and(|adt| adt.is_unsafe_cell()) { + return true; + } + // We do not use `ty.is_freeze` here, because that requires revealing opaque types, which // requires borrowck, which in turn will invoke mir_const_qualifs again, causing a cycle error. // Instead we invoke an obligation context manually, and provide the opaque type inference settings // that allow the trait solver to just error out instead of cycling. let freeze_def_id = cx.tcx.require_lang_item(LangItem::Freeze, Some(cx.body.span)); - + // FIXME(#132279): Once we've got a typing mode which reveals opaque types using the HIR + // typeck results without causing query cycles, we should use this here instead of defining + // opaque types. + let typing_env = ty::TypingEnv { + typing_mode: ty::TypingMode::analysis_in_body( + cx.tcx, + cx.body.source.def_id().expect_local(), + ), + param_env: cx.typing_env.param_env, + }; + let (infcx, param_env) = cx.tcx.infer_ctxt().build_with_typing_env(typing_env); + let ocx = ObligationCtxt::new(&infcx); let obligation = Obligation::new( cx.tcx, ObligationCause::dummy_with_span(cx.body.span), - cx.param_env, + param_env, ty::TraitRef::new(cx.tcx, freeze_def_id, [ty::GenericArg::from(ty)]), ); - - // FIXME(#132279): This should eventually use the already defined hidden types. - let infcx = cx.tcx.infer_ctxt().build(ty::TypingMode::analysis_in_body( - cx.tcx, - cx.body.source.def_id().expect_local(), - )); - let ocx = ObligationCtxt::new(&infcx); ocx.register_obligation(obligation); let errors = ocx.select_all_or_error(); !errors.is_empty() } - fn in_adt_inherently<'tcx>( - _cx: &ConstCx<'_, 'tcx>, - adt: AdtDef<'tcx>, - _: GenericArgsRef<'tcx>, - ) -> bool { + fn is_structural_in_adt_value<'tcx>(_cx: &ConstCx<'_, 'tcx>, adt: AdtDef<'tcx>) -> bool { // Exactly one type, `UnsafeCell`, has the `HasMutInterior` qualif inherently. // It arises structurally for all other types. - adt.is_unsafe_cell() - } - - fn deref_structural<'tcx>(_cx: &ConstCx<'_, 'tcx>) -> bool { - false + !adt.is_unsafe_cell() } } @@ -150,25 +140,18 @@ pub struct NeedsDrop; impl Qualif for NeedsDrop { const ANALYSIS_NAME: &'static str = "flow_needs_drop"; const IS_CLEARED_ON_MOVE: bool = true; + const ALLOW_PROMOTED: bool = true; fn in_qualifs(qualifs: &ConstQualifs) -> bool { qualifs.needs_drop } fn in_any_value_of_ty<'tcx>(cx: &ConstCx<'_, 'tcx>, ty: Ty<'tcx>) -> bool { - ty.needs_drop(cx.tcx, cx.param_env) + ty.needs_drop(cx.tcx, cx.typing_env) } - fn in_adt_inherently<'tcx>( - cx: &ConstCx<'_, 'tcx>, - adt: AdtDef<'tcx>, - _: GenericArgsRef<'tcx>, - ) -> bool { - adt.has_dtor(cx.tcx) - } - - fn deref_structural<'tcx>(_cx: &ConstCx<'_, 'tcx>) -> bool { - false + fn is_structural_in_adt_value<'tcx>(cx: &ConstCx<'_, 'tcx>, adt: AdtDef<'tcx>) -> bool { + !adt.has_dtor(cx.tcx) } } @@ -187,25 +170,46 @@ impl Qualif for NeedsNonConstDrop { #[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) { + // If this doesn't need drop at all, then don't select `~const Destruct`. + if !ty.needs_drop(cx.tcx, cx.typing_env) { return false; } - // FIXME(const_trait_impl): Reimplement const drop checking. - NeedsDrop::in_any_value_of_ty(cx, ty) - } - - fn in_adt_inherently<'tcx>( - cx: &ConstCx<'_, 'tcx>, - adt: AdtDef<'tcx>, - _: GenericArgsRef<'tcx>, - ) -> bool { - adt.has_non_const_dtor(cx.tcx) + // We check that the type is `~const Destruct` since that will verify that + // the type is both `~const Drop` (if a drop impl exists for the adt), *and* + // that the components of this type are also `~const Destruct`. This + // amounts to verifying that there are no values in this ADT that may have + // a non-const drop. + let destruct_def_id = cx.tcx.require_lang_item(LangItem::Destruct, Some(cx.body.span)); + let (infcx, param_env) = cx.tcx.infer_ctxt().build_with_typing_env(cx.typing_env); + let ocx = ObligationCtxt::new(&infcx); + ocx.register_obligation(Obligation::new( + cx.tcx, + ObligationCause::misc(cx.body.span, cx.def_id()), + param_env, + ty::Binder::dummy(ty::TraitRef::new(cx.tcx, destruct_def_id, [ty])) + .to_host_effect_clause(cx.tcx, match cx.const_kind() { + rustc_hir::ConstContext::ConstFn => ty::BoundConstness::Maybe, + rustc_hir::ConstContext::Static(_) | rustc_hir::ConstContext::Const { .. } => { + ty::BoundConstness::Const + } + }), + )); + !ocx.select_all_or_error().is_empty() } - fn deref_structural<'tcx>(_cx: &ConstCx<'_, 'tcx>) -> bool { - false + fn is_structural_in_adt_value<'tcx>(cx: &ConstCx<'_, 'tcx>, adt: AdtDef<'tcx>) -> bool { + // As soon as an ADT has a destructor, then the drop becomes non-structural + // in its value since: + // 1. The destructor may have `~const` bounds which are not present on the type. + // Someone needs to check that those are satisfied. + // While this could be instead satisfied by checking that the `~const Drop` + // impl holds (i.e. replicating part of the `in_any_value_of_ty` logic above), + // even in this case, we have another problem, which is, + // 2. The destructor may *modify* the operand being dropped, so even if we + // did recurse on the components of the operand, we may not be even dropping + // the same values that were present before the custom destructor was invoked. + !adt.has_dtor(cx.tcx) } } @@ -257,14 +261,15 @@ where Rvalue::Aggregate(kind, operands) => { // Return early if we know that the struct or enum being constructed is always // qualified. - if let AggregateKind::Adt(adt_did, _, args, ..) = **kind { + if let AggregateKind::Adt(adt_did, ..) = **kind { let def = cx.tcx.adt_def(adt_did); - if Q::in_adt_inherently(cx, def, args) { - return true; - } // Don't do any value-based reasoning for unions. - if def.is_union() && Q::in_any_value_of_ty(cx, rvalue.ty(cx.body, cx.tcx)) { - return true; + // Also, if the ADT is not structural in its fields, + // then we cannot recurse on its fields. Instead, + // we fall back to checking the qualif for *any* value + // of the ADT. + if def.is_union() || !Q::is_structural_in_adt_value(cx, def) { + return Q::in_any_value_of_ty(cx, rvalue.ty(cx.body, cx.tcx)); } } @@ -301,7 +306,11 @@ where return false; } - if matches!(elem, ProjectionElem::Deref) && !Q::deref_structural(cx) { + // `Deref` currently unconditionally "qualifies" if `in_any_value_of_ty` returns true, + // i.e., we treat all qualifs as non-structural for deref projections. Generally, + // we can say very little about `*ptr` even if we know that `ptr` satisfies all + // sorts of properties. + if matches!(elem, ProjectionElem::Deref) { // We have to assume that this qualifies. return true; } diff --git a/compiler/rustc_const_eval/src/check_consts/resolver.rs b/compiler/rustc_const_eval/src/check_consts/resolver.rs index 74eb6b37fbb..763c37a41af 100644 --- a/compiler/rustc_const_eval/src/check_consts/resolver.rs +++ b/compiler/rustc_const_eval/src/check_consts/resolver.rs @@ -120,7 +120,7 @@ where /// /// [rust-lang/unsafe-code-guidelines#134]: https://github.com/rust-lang/unsafe-code-guidelines/issues/134 fn shared_borrow_allows_mutation(&self, place: mir::Place<'tcx>) -> bool { - !place.ty(self.ccx.body, self.ccx.tcx).ty.is_freeze(self.ccx.tcx, self.ccx.param_env) + !place.ty(self.ccx.body, self.ccx.tcx).ty.is_freeze(self.ccx.tcx, self.ccx.typing_env) } } @@ -329,7 +329,7 @@ where self.transfer_function(state).initialize_state(); } - fn apply_statement_effect( + fn apply_primary_statement_effect( &mut self, state: &mut Self::Domain, statement: &mir::Statement<'tcx>, @@ -338,7 +338,7 @@ where self.transfer_function(state).visit_statement(statement, location); } - fn apply_terminator_effect<'mir>( + fn apply_primary_terminator_effect<'mir>( &mut self, state: &mut Self::Domain, terminator: &'mir mir::Terminator<'tcx>, diff --git a/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs b/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs index e49d702127d..817acfcca74 100644 --- a/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs +++ b/compiler/rustc_const_eval/src/const_eval/dummy_machine.rs @@ -168,9 +168,9 @@ impl<'tcx> interpret::Machine<'tcx> for DummyMachine { }) } - fn expose_ptr( - _ecx: &mut InterpCx<'tcx, Self>, - _ptr: interpret::Pointer<Self::Provenance>, + fn expose_provenance( + _ecx: &InterpCx<'tcx, Self>, + _provenance: Self::Provenance, ) -> interpret::InterpResult<'tcx> { unimplemented!() } diff --git a/compiler/rustc_const_eval/src/const_eval/error.rs b/compiler/rustc_const_eval/src/const_eval/error.rs index 6686413bf02..fee7287951d 100644 --- a/compiler/rustc_const_eval/src/const_eval/error.rs +++ b/compiler/rustc_const_eval/src/const_eval/error.rs @@ -139,12 +139,14 @@ where match error { // Don't emit a new diagnostic for these errors, they are already reported elsewhere or // should remain silent. + err_inval!(AlreadyReported(info)) => ErrorHandled::Reported(info, span), err_inval!(Layout(LayoutError::Unknown(_))) | err_inval!(TooGeneric) => { ErrorHandled::TooGeneric(span) } - err_inval!(AlreadyReported(guar)) => ErrorHandled::Reported(guar, span), err_inval!(Layout(LayoutError::ReferencesError(guar))) => { - ErrorHandled::Reported(ReportedErrorInfo::tainted_by_errors(guar), span) + // This can occur in infallible promoteds e.g. when a non-existent type or field is + // encountered. + ErrorHandled::Reported(ReportedErrorInfo::allowed_in_infallible(guar), span) } // Report remaining errors. _ => { @@ -152,13 +154,25 @@ where let span = span.substitute_dummy(our_span); let err = mk(span, frames); let mut err = tcx.dcx().create_err(err); + // We allow invalid programs in infallible promoteds since invalid layouts can occur + // anyway (e.g. due to size overflow). And we allow OOM as that can happen any time. + let allowed_in_infallible = matches!( + error, + InterpErrorKind::ResourceExhaustion(_) | InterpErrorKind::InvalidProgram(_) + ); let msg = error.diagnostic_message(); error.add_args(&mut err); // Use *our* span to label the interp error err.span_label(our_span, msg); - ErrorHandled::Reported(err.emit().into(), span) + let g = err.emit(); + let reported = if allowed_in_infallible { + ReportedErrorInfo::allowed_in_infallible(g) + } else { + ReportedErrorInfo::const_eval_error(g) + }; + ErrorHandled::Reported(reported, span) } } } diff --git a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs index 81b9d73b952..ce8eceebdf8 100644 --- a/compiler/rustc_const_eval/src/const_eval/eval_queries.rs +++ b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs @@ -3,14 +3,13 @@ use std::sync::atomic::Ordering::Relaxed; use either::{Left, Right}; use rustc_abi::{self as abi, BackendRepr}; use rustc_hir::def::DefKind; -use rustc_middle::bug; -use rustc_middle::mir::interpret::{AllocId, ErrorHandled, InterpErrorInfo}; +use rustc_middle::mir::interpret::{AllocId, ErrorHandled, InterpErrorInfo, ReportedErrorInfo}; use rustc_middle::mir::{self, ConstAlloc, ConstValue}; use rustc_middle::query::TyCtxtAt; -use rustc_middle::traits::Reveal; -use rustc_middle::ty::layout::LayoutOf; +use rustc_middle::ty::layout::{HasTypingEnv, LayoutOf}; use rustc_middle::ty::print::with_no_trimmed_paths; use rustc_middle::ty::{self, Ty, TyCtxt}; +use rustc_middle::{bug, throw_inval}; use rustc_span::def_id::LocalDefId; use rustc_span::{DUMMY_SP, Span}; use tracing::{debug, instrument, trace}; @@ -31,7 +30,6 @@ fn eval_body_using_ecx<'tcx, R: InterpretationResult<'tcx>>( cid: GlobalId<'tcx>, body: &'tcx mir::Body<'tcx>, ) -> InterpResult<'tcx, R> { - trace!(?ecx.param_env); let tcx = *ecx.tcx; assert!( cid.promoted.is_some() @@ -95,18 +93,18 @@ fn eval_body_using_ecx<'tcx, R: InterpretationResult<'tcx>>( match intern_result { Ok(()) => {} Err(InternResult::FoundDanglingPointer) => { - return Err(ecx - .tcx - .dcx() - .emit_err(errors::DanglingPtrInFinal { span: ecx.tcx.span, kind: intern_kind })) - .into(); + throw_inval!(AlreadyReported(ReportedErrorInfo::non_const_eval_error( + ecx.tcx + .dcx() + .emit_err(errors::DanglingPtrInFinal { span: ecx.tcx.span, kind: intern_kind }), + ))); } Err(InternResult::FoundBadMutablePointer) => { - return Err(ecx - .tcx - .dcx() - .emit_err(errors::MutablePtrInFinal { span: ecx.tcx.span, kind: intern_kind })) - .into(); + throw_inval!(AlreadyReported(ReportedErrorInfo::non_const_eval_error( + ecx.tcx + .dcx() + .emit_err(errors::MutablePtrInFinal { span: ecx.tcx.span, kind: intern_kind }), + ))); } } @@ -126,14 +124,14 @@ fn eval_body_using_ecx<'tcx, R: InterpretationResult<'tcx>>( pub(crate) fn mk_eval_cx_to_read_const_val<'tcx>( tcx: TyCtxt<'tcx>, root_span: Span, - param_env: ty::ParamEnv<'tcx>, + typing_env: ty::TypingEnv<'tcx>, can_access_mut_global: CanAccessMutGlobal, ) -> CompileTimeInterpCx<'tcx> { - debug!("mk_eval_cx: {:?}", param_env); + debug!("mk_eval_cx: {:?}", typing_env); InterpCx::new( tcx, root_span, - param_env, + typing_env, CompileTimeMachine::new(can_access_mut_global, CheckAlignment::No), ) } @@ -142,11 +140,11 @@ pub(crate) fn mk_eval_cx_to_read_const_val<'tcx>( /// Returns both the context and an `OpTy` that represents the constant. pub fn mk_eval_cx_for_const_val<'tcx>( tcx: TyCtxtAt<'tcx>, - param_env: ty::ParamEnv<'tcx>, + typing_env: ty::TypingEnv<'tcx>, val: mir::ConstValue<'tcx>, ty: Ty<'tcx>, ) -> Option<(CompileTimeInterpCx<'tcx>, OpTy<'tcx>)> { - let ecx = mk_eval_cx_to_read_const_val(tcx.tcx, tcx.span, param_env, CanAccessMutGlobal::No); + let ecx = mk_eval_cx_to_read_const_val(tcx.tcx, tcx.span, typing_env, CanAccessMutGlobal::No); // FIXME: is it a problem to discard the error here? let op = ecx.const_val_to_op(val, ty, None).discard_err()?; Some((ecx, op)) @@ -221,7 +219,7 @@ pub(super) fn op_to_const<'tcx>( let pointee_ty = imm.layout.ty.builtin_deref(false).unwrap(); // `false` = no raw ptrs debug_assert!( matches!( - ecx.tcx.struct_tail_for_codegen(pointee_ty, ecx.param_env).kind(), + ecx.tcx.struct_tail_for_codegen(pointee_ty, ecx.typing_env()).kind(), ty::Str | ty::Slice(..), ), "`ConstValue::Slice` is for slice-tailed types only, but got {}", @@ -245,7 +243,7 @@ pub(super) fn op_to_const<'tcx>( pub(crate) fn turn_into_const_value<'tcx>( tcx: TyCtxt<'tcx>, constant: ConstAlloc<'tcx>, - key: ty::ParamEnvAnd<'tcx, GlobalId<'tcx>>, + key: ty::PseudoCanonicalInput<'tcx, GlobalId<'tcx>>, ) -> ConstValue<'tcx> { let cid = key.value; let def_id = cid.instance.def.def_id(); @@ -254,7 +252,7 @@ pub(crate) fn turn_into_const_value<'tcx>( let ecx = mk_eval_cx_to_read_const_val( tcx, tcx.def_span(key.value.instance.def_id()), - key.param_env, + key.typing_env, CanAccessMutGlobal::from(is_static), ); @@ -274,21 +272,16 @@ pub(crate) fn turn_into_const_value<'tcx>( #[instrument(skip(tcx), level = "debug")] pub fn eval_to_const_value_raw_provider<'tcx>( tcx: TyCtxt<'tcx>, - key: ty::ParamEnvAnd<'tcx, GlobalId<'tcx>>, + key: ty::PseudoCanonicalInput<'tcx, GlobalId<'tcx>>, ) -> ::rustc_middle::mir::interpret::EvalToConstValueResult<'tcx> { - // Const eval always happens in Reveal::All mode in order to be able to use the hidden types of - // opaque types. This is needed for trivial things like `size_of`, but also for using associated - // types that are not specified in the opaque type. - assert_eq!(key.param_env.reveal(), Reveal::All); - // We call `const_eval` for zero arg intrinsics, too, in order to cache their value. // Catch such calls and evaluate them instead of trying to load a constant's MIR. if let ty::InstanceKind::Intrinsic(def_id) = key.value.instance.def { - let ty = key.value.instance.ty(tcx, key.param_env); + let ty = key.value.instance.ty(tcx, key.typing_env); let ty::FnDef(_, args) = ty.kind() else { bug!("intrinsic with type {:?}", ty); }; - return eval_nullary_intrinsic(tcx, key.param_env, def_id, args).report_err().map_err( + return eval_nullary_intrinsic(tcx, key.typing_env, def_id, args).report_err().map_err( |error| { let span = tcx.def_span(def_id); @@ -315,7 +308,7 @@ pub fn eval_static_initializer_provider<'tcx>( let instance = ty::Instance::mono(tcx, def_id.to_def_id()); let cid = rustc_middle::mir::interpret::GlobalId { instance, promoted: None }; - eval_in_interpreter(tcx, cid, ty::ParamEnv::reveal_all()) + eval_in_interpreter(tcx, cid, ty::TypingEnv::fully_monomorphized()) } pub trait InterpretationResult<'tcx> { @@ -340,16 +333,14 @@ impl<'tcx> InterpretationResult<'tcx> for ConstAlloc<'tcx> { #[instrument(skip(tcx), level = "debug")] pub fn eval_to_allocation_raw_provider<'tcx>( tcx: TyCtxt<'tcx>, - key: ty::ParamEnvAnd<'tcx, GlobalId<'tcx>>, + key: ty::PseudoCanonicalInput<'tcx, GlobalId<'tcx>>, ) -> ::rustc_middle::mir::interpret::EvalToAllocationRawResult<'tcx> { // This shouldn't be used for statics, since statics are conceptually places, // not values -- so what we do here could break pointer identity. assert!(key.value.promoted.is_some() || !tcx.is_static(key.value.instance.def_id())); - // Const eval always happens in Reveal::All mode in order to be able to use the hidden types of - // opaque types. This is needed for trivial things like `size_of`, but also for using associated - // types that are not specified in the opaque type. - - assert_eq!(key.param_env.reveal(), Reveal::All); + // Const eval always happens in PostAnalysis mode . See the comment in + // `InterpCx::new` for more details. + debug_assert_eq!(key.typing_env.typing_mode, ty::TypingMode::PostAnalysis); if cfg!(debug_assertions) { // Make sure we format the instance even if we do not print it. // This serves as a regression test against an ICE on printing. @@ -360,13 +351,13 @@ pub fn eval_to_allocation_raw_provider<'tcx>( trace!("const eval: {:?} ({})", key, instance); } - eval_in_interpreter(tcx, key.value, key.param_env) + eval_in_interpreter(tcx, key.value, key.typing_env) } fn eval_in_interpreter<'tcx, R: InterpretationResult<'tcx>>( tcx: TyCtxt<'tcx>, cid: GlobalId<'tcx>, - param_env: ty::ParamEnv<'tcx>, + typing_env: ty::TypingEnv<'tcx>, ) -> Result<R, ErrorHandled> { let def = cid.instance.def.def_id(); let is_static = tcx.is_static(def); @@ -374,7 +365,7 @@ fn eval_in_interpreter<'tcx, R: InterpretationResult<'tcx>>( let mut ecx = InterpCx::new( tcx, tcx.def_span(def), - param_env, + typing_env, // Statics (and promoteds inside statics) may access mutable global memory, because unlike consts // they do not have to behave "as if" they were evaluated at runtime. // For consts however we want to ensure they behave "as if" they were evaluated at runtime, @@ -472,8 +463,9 @@ fn report_validation_error<'tcx>( backtrace.print_backtrace(); let bytes = ecx.print_alloc_bytes_for_diagnostics(alloc_id); - let (size, align, _) = ecx.get_alloc_info(alloc_id); - let raw_bytes = errors::RawBytesNote { size: size.bytes(), align: align.bytes(), bytes }; + let info = ecx.get_alloc_info(alloc_id); + let raw_bytes = + errors::RawBytesNote { size: info.size.bytes(), align: info.align.bytes(), bytes }; crate::const_eval::report( *ecx.tcx, diff --git a/compiler/rustc_const_eval/src/const_eval/fn_queries.rs b/compiler/rustc_const_eval/src/const_eval/fn_queries.rs index beff0cd99fc..babf99c4c1f 100644 --- a/compiler/rustc_const_eval/src/const_eval/fn_queries.rs +++ b/compiler/rustc_const_eval/src/const_eval/fn_queries.rs @@ -4,27 +4,29 @@ use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_middle::query::Providers; use rustc_middle::ty::TyCtxt; -pub fn is_parent_const_impl_raw(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool { +fn parent_impl_constness(tcx: TyCtxt<'_>, def_id: LocalDefId) -> hir::Constness { let parent_id = tcx.local_parent(def_id); - matches!(tcx.def_kind(parent_id), DefKind::Impl { .. }) - && tcx.constness(parent_id) == hir::Constness::Const + if matches!(tcx.def_kind(parent_id), DefKind::Impl { .. }) + && let Some(header) = tcx.impl_trait_header(parent_id) + { + header.constness + } else { + hir::Constness::NotConst + } } -/// Checks whether an item is considered to be `const`. If it is a constructor, anonymous const, -/// const block, const item or associated const, it is const. If it is a trait impl/function, +/// Checks whether an item is considered to be `const`. If it is a constructor, it is const. +/// If it is an assoc method or function, /// return if it has a `const` modifier. If it is an intrinsic, report whether said intrinsic -/// has a `rustc_const_{un,}stable` attribute. Otherwise, return `Constness::NotConst`. +/// has a `rustc_const_{un,}stable` attribute. Otherwise, panic. fn constness(tcx: TyCtxt<'_>, def_id: LocalDefId) -> hir::Constness { let node = tcx.hir_node_by_def_id(def_id); match node { - hir::Node::Ctor(_) - | hir::Node::AnonConst(_) - | hir::Node::ConstBlock(_) + hir::Node::Ctor(hir::VariantData::Tuple(..)) | hir::Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(..), .. }) => { hir::Constness::Const } - hir::Node::Item(hir::Item { kind: hir::ItemKind::Impl(impl_), .. }) => impl_.constness, hir::Node::ForeignItem(_) => { // Foreign items cannot be evaluated at compile-time. hir::Constness::NotConst @@ -38,10 +40,12 @@ fn constness(tcx: TyCtxt<'_>, def_id: LocalDefId) -> hir::Constness { // If the function itself is not annotated with `const`, it may still be a `const fn` // if it resides in a const trait impl. - let is_const = is_parent_const_impl_raw(tcx, def_id); - if is_const { hir::Constness::Const } else { hir::Constness::NotConst } + parent_impl_constness(tcx, def_id) } else { - hir::Constness::NotConst + tcx.dcx().span_bug( + tcx.def_span(def_id), + format!("should not be requesting the constness of items that can't be const: {node:#?}: {:?}", tcx.def_kind(def_id)) + ) } } } @@ -53,9 +57,8 @@ fn is_promotable_const_fn(tcx: TyCtxt<'_>, def_id: DefId) -> bool { Some(stab) => { if cfg!(debug_assertions) && stab.promotable { let sig = tcx.fn_sig(def_id); - assert_eq!( - sig.skip_binder().safety(), - hir::Safety::Safe, + assert!( + sig.skip_binder().safety().is_safe(), "don't mark const unsafe fns as promotable", // https://github.com/rust-lang/rust/pull/53851#issuecomment-418760682 ); diff --git a/compiler/rustc_const_eval/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs index 62115aef4a7..9c660ef0b18 100644 --- a/compiler/rustc_const_eval/src/const_eval/machine.rs +++ b/compiler/rustc_const_eval/src/const_eval/machine.rs @@ -8,12 +8,12 @@ use rustc_data_structures::fx::{FxHashMap, FxIndexMap, IndexEntry}; use rustc_hir::def_id::{DefId, LocalDefId}; use rustc_hir::{self as hir, CRATE_HIR_ID, LangItem}; use rustc_middle::mir::AssertMessage; +use rustc_middle::mir::interpret::ReportedErrorInfo; use rustc_middle::query::TyCtxtAt; -use rustc_middle::ty::layout::TyAndLayout; +use rustc_middle::ty::layout::{HasTypingEnv, TyAndLayout}; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_middle::{bug, mir}; -use rustc_span::Span; -use rustc_span::symbol::{Symbol, sym}; +use rustc_span::{Span, Symbol, sym}; use tracing::debug; use super::error::*; @@ -21,9 +21,8 @@ use crate::errors::{LongRunning, LongRunningWarn}; use crate::fluent_generated as fluent; use crate::interpret::{ self, AllocId, AllocRange, ConstAllocation, CtfeProvenance, FnArg, Frame, GlobalAlloc, ImmTy, - InterpCx, InterpResult, MPlaceTy, OpTy, Pointer, RangeSet, Scalar, compile_time_machine, - interp_ok, throw_exhaust, throw_inval, throw_ub, throw_ub_custom, throw_unsup, - throw_unsup_format, + InterpCx, InterpResult, MPlaceTy, OpTy, RangeSet, Scalar, compile_time_machine, interp_ok, + throw_exhaust, throw_inval, throw_ub, throw_ub_custom, throw_unsup, throw_unsup_format, }; /// When hitting this many interpreted terminators we emit a deny by default lint @@ -251,7 +250,7 @@ impl<'tcx> CompileTimeInterpCx<'tcx> { let const_def_id = self.tcx.require_lang_item(LangItem::ConstPanicFmt, None); let new_instance = ty::Instance::expect_resolve( *self.tcx, - ty::ParamEnv::reveal_all(), + self.typing_env(), const_def_id, instance.args, self.cur_span(), @@ -263,6 +262,12 @@ impl<'tcx> CompileTimeInterpCx<'tcx> { } /// See documentation on the `ptr_guaranteed_cmp` intrinsic. + /// Returns `2` if the result is unknown. + /// Returns `1` if the pointers are guaranteed equal. + /// Returns `0` if the pointers are guaranteed inequal. + /// + /// Note that this intrinsic is exposed on stable for comparison with null. In other words, any + /// change to this function that affects comparison with null is insta-stable! fn guaranteed_cmp(&mut self, a: Scalar, b: Scalar) -> InterpResult<'tcx, u8> { interp_ok(match (a, b) { // Comparisons between integers are always known. @@ -557,7 +562,7 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> { .tcx .dcx() .span_delayed_bug(span, "The deny lint should have already errored"); - throw_inval!(AlreadyReported(guard.into())); + throw_inval!(AlreadyReported(ReportedErrorInfo::allowed_in_infallible(guard))); } } else if new_steps > start && new_steps.is_power_of_two() { // Only report after a certain number of terminators have been evaluated and the @@ -579,7 +584,10 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> { } #[inline(always)] - fn expose_ptr(_ecx: &mut InterpCx<'tcx, Self>, _ptr: Pointer) -> InterpResult<'tcx> { + fn expose_provenance( + _ecx: &InterpCx<'tcx, Self>, + _provenance: Self::Provenance, + ) -> InterpResult<'tcx> { // This is only reachable with -Zunleash-the-miri-inside-of-you. throw_unsup_format!("exposing pointers is not possible at compile-time") } @@ -660,7 +668,7 @@ impl<'tcx> interpret::Machine<'tcx> for CompileTimeMachine<'tcx> { .is_some_and(|p| !p.immutable()) { // That next check is expensive, that's why we have all the guards above. - let is_immutable = ty.is_freeze(*ecx.tcx, ecx.param_env); + let is_immutable = ty.is_freeze(*ecx.tcx, ecx.typing_env()); let place = ecx.ref_to_mplace(val)?; let new_place = if is_immutable { place.map_provenance(CtfeProvenance::as_immutable) diff --git a/compiler/rustc_const_eval/src/const_eval/mod.rs b/compiler/rustc_const_eval/src/const_eval/mod.rs index d5012236c34..34f795bda75 100644 --- a/compiler/rustc_const_eval/src/const_eval/mod.rs +++ b/compiler/rustc_const_eval/src/const_eval/mod.rs @@ -2,6 +2,7 @@ use rustc_abi::VariantIdx; use rustc_middle::query::{Key, TyCtxtAt}; +use rustc_middle::ty::layout::LayoutOf; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_middle::{bug, mir}; use tracing::instrument; @@ -38,8 +39,8 @@ pub(crate) fn try_destructure_mir_constant_for_user_output<'tcx>( val: mir::ConstValue<'tcx>, ty: Ty<'tcx>, ) -> Option<mir::DestructuredConstant<'tcx>> { - let param_env = ty::ParamEnv::reveal_all(); - let (ecx, op) = mk_eval_cx_for_const_val(tcx, param_env, val, ty)?; + let typing_env = ty::TypingEnv::fully_monomorphized(); + let (ecx, op) = mk_eval_cx_for_const_val(tcx, typing_env, val, ty)?; // We go to `usize` as we cannot allocate anything bigger anyway. let (field_count, variant, down) = match ty.kind() { @@ -76,12 +77,15 @@ pub fn tag_for_variant_provider<'tcx>( ) -> Option<ty::ScalarInt> { assert!(ty.is_enum()); + // FIXME: This uses an empty `TypingEnv` even though + // it may be used by a generic CTFE. let ecx = InterpCx::new( tcx, ty.default_span(tcx), - ty::ParamEnv::reveal_all(), + ty::TypingEnv::fully_monomorphized(), crate::const_eval::DummyMachine, ); - ecx.tag_for_variant(ty, variant_index).unwrap().map(|(tag, _tag_field)| tag) + let layout = ecx.layout_of(ty).unwrap(); + ecx.tag_for_variant(layout, variant_index).unwrap().map(|(tag, _tag_field)| tag) } diff --git a/compiler/rustc_const_eval/src/const_eval/valtrees.rs b/compiler/rustc_const_eval/src/const_eval/valtrees.rs index ea88b2ed22e..6f51b09323d 100644 --- a/compiler/rustc_const_eval/src/const_eval/valtrees.rs +++ b/compiler/rustc_const_eval/src/const_eval/valtrees.rs @@ -1,6 +1,6 @@ use rustc_abi::{BackendRepr, VariantIdx}; use rustc_data_structures::stack::ensure_sufficient_stack; -use rustc_middle::mir::interpret::{EvalToValTreeResult, GlobalId}; +use rustc_middle::mir::interpret::{EvalToValTreeResult, GlobalId, ReportedErrorInfo}; use rustc_middle::ty::layout::{LayoutCx, LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, ScalarInt, Ty, TyCtxt}; use rustc_middle::{bug, mir}; @@ -228,16 +228,19 @@ fn create_valtree_place<'tcx>( /// Evaluates a constant and turns it into a type-level constant value. pub(crate) fn eval_to_valtree<'tcx>( tcx: TyCtxt<'tcx>, - param_env: ty::ParamEnv<'tcx>, + typing_env: ty::TypingEnv<'tcx>, cid: GlobalId<'tcx>, ) -> EvalToValTreeResult<'tcx> { - let const_alloc = tcx.eval_to_allocation_raw(param_env.and(cid))?; + // Const eval always happens in PostAnalysis mode . See the comment in + // `InterpCx::new` for more details. + debug_assert_eq!(typing_env.typing_mode, ty::TypingMode::PostAnalysis); + let const_alloc = tcx.eval_to_allocation_raw(typing_env.as_query_input(cid))?; // FIXME Need to provide a span to `eval_to_valtree` let ecx = mk_eval_cx_to_read_const_val( tcx, DUMMY_SP, - param_env, + typing_env, // It is absolutely crucial for soundness that // we do not read from mutable memory. CanAccessMutGlobal::No, @@ -258,7 +261,7 @@ pub(crate) fn eval_to_valtree<'tcx>( ValTreeCreationError::NodesOverflow => { let handled = tcx.dcx().emit_err(MaxNumNodesInConstErr { span, global_const_id }); - Err(handled.into()) + Err(ReportedErrorInfo::allowed_in_infallible(handled).into()) } ValTreeCreationError::NonSupportedType(ty) => Ok(Err(ty)), } @@ -272,7 +275,8 @@ pub(crate) fn eval_to_valtree<'tcx>( #[instrument(skip(tcx), level = "debug", ret)] pub fn valtree_to_const_value<'tcx>( tcx: TyCtxt<'tcx>, - param_env_ty: ty::ParamEnvAnd<'tcx, Ty<'tcx>>, + typing_env: ty::TypingEnv<'tcx>, + ty: Ty<'tcx>, valtree: ty::ValTree<'tcx>, ) -> mir::ConstValue<'tcx> { // Basic idea: We directly construct `Scalar` values from trivial `ValTree`s @@ -281,9 +285,6 @@ pub fn valtree_to_const_value<'tcx>( // the `ValTree` and using `place_projection` and `place_field` to // create inner `MPlace`s which are filled recursively. // FIXME Does this need an example? - - let (param_env, ty) = param_env_ty.into_parts(); - match *ty.kind() { ty::FnDef(..) => { assert!(valtree.unwrap_branch().is_empty()); @@ -297,16 +298,17 @@ pub fn valtree_to_const_value<'tcx>( ), } } - ty::Pat(ty, _) => valtree_to_const_value(tcx, param_env.and(ty), valtree), + ty::Pat(ty, _) => valtree_to_const_value(tcx, typing_env, ty, valtree), ty::Ref(_, inner_ty, _) => { let mut ecx = - mk_eval_cx_to_read_const_val(tcx, DUMMY_SP, param_env, CanAccessMutGlobal::No); + mk_eval_cx_to_read_const_val(tcx, DUMMY_SP, typing_env, CanAccessMutGlobal::No); let imm = valtree_to_ref(&mut ecx, valtree, inner_ty); - let imm = ImmTy::from_immediate(imm, tcx.layout_of(param_env_ty).unwrap()); + let imm = + ImmTy::from_immediate(imm, tcx.layout_of(typing_env.as_query_input(ty)).unwrap()); op_to_const(&ecx, &imm.into(), /* for diagnostics */ false) } ty::Tuple(_) | ty::Array(_, _) | ty::Adt(..) => { - let layout = tcx.layout_of(param_env_ty).unwrap(); + let layout = tcx.layout_of(typing_env.as_query_input(ty)).unwrap(); if layout.is_zst() { // Fast path to avoid some allocations. return mir::ConstValue::ZeroSized; @@ -319,16 +321,16 @@ pub fn valtree_to_const_value<'tcx>( let branches = valtree.unwrap_branch(); // Find the non-ZST field. (There can be aligned ZST!) for (i, &inner_valtree) in branches.iter().enumerate() { - let field = layout.field(&LayoutCx::new(tcx, param_env), i); + let field = layout.field(&LayoutCx::new(tcx, typing_env), i); if !field.is_zst() { - return valtree_to_const_value(tcx, param_env.and(field.ty), inner_valtree); + return valtree_to_const_value(tcx, typing_env, field.ty, inner_valtree); } } bug!("could not find non-ZST field during in {layout:#?}"); } let mut ecx = - mk_eval_cx_to_read_const_val(tcx, DUMMY_SP, param_env, CanAccessMutGlobal::No); + mk_eval_cx_to_read_const_val(tcx, DUMMY_SP, typing_env, CanAccessMutGlobal::No); // Need to create a place for this valtree. let place = create_valtree_place(&mut ecx, layout, valtree); diff --git a/compiler/rustc_const_eval/src/errors.rs b/compiler/rustc_const_eval/src/errors.rs index 14e8bebbb18..80236ee05b7 100644 --- a/compiler/rustc_const_eval/src/errors.rs +++ b/compiler/rustc_const_eval/src/errors.rs @@ -177,6 +177,16 @@ pub(crate) struct NonConstFmtMacroCall { } #[derive(Diagnostic)] +#[diag(const_eval_conditionally_const_call)] +pub(crate) struct ConditionallyConstCall { + #[primary_span] + pub span: Span, + pub def_path_str: String, + pub def_descr: &'static str, + pub kind: ConstContext, +} + +#[derive(Diagnostic)] #[diag(const_eval_non_const_fn_call, code = E0015)] pub(crate) struct NonConstFnCall { #[primary_span] @@ -401,7 +411,7 @@ pub struct LiveDrop<'tcx> { pub kind: ConstContext, pub dropped_ty: Ty<'tcx>, #[label(const_eval_dropped_at_label)] - pub dropped_at: Option<Span>, + pub dropped_at: Span, } #[derive(Diagnostic)] diff --git a/compiler/rustc_const_eval/src/interpret/call.rs b/compiler/rustc_const_eval/src/interpret/call.rs index ef0902e4226..ed4a1a9e647 100644 --- a/compiler/rustc_const_eval/src/interpret/call.rs +++ b/compiler/rustc_const_eval/src/interpret/call.rs @@ -215,7 +215,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // Even if `ty` is normalized, the search for the unsized tail will project // to fields, which can yield non-normalized types. So we need to provide a // normalization function. - let normalize = |ty| self.tcx.normalize_erasing_regions(self.param_env, ty); + let normalize = |ty| self.tcx.normalize_erasing_regions(self.typing_env, ty); ty.ptr_metadata_ty(*self.tcx, normalize) }; return interp_ok(meta_ty(caller) == meta_ty(callee)); @@ -662,7 +662,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // Doesn't have to be a `dyn Trait`, but the unsized tail must be `dyn Trait`. // (For that reason we also cannot use `unpack_dyn_trait`.) let receiver_tail = - self.tcx.struct_tail_for_codegen(receiver_place.layout.ty, self.param_env); + self.tcx.struct_tail_for_codegen(receiver_place.layout.ty, self.typing_env); let ty::Dynamic(receiver_trait, _, ty::Dyn) = receiver_tail.kind() else { span_bug!( self.cur_span(), @@ -704,7 +704,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let concrete_method = Instance::expect_resolve_for_vtable( tcx, - self.param_env, + self.typing_env, def_id, instance.args.rebase_onto(tcx, trait_def_id, concrete_trait_ref.args), self.cur_span(), diff --git a/compiler/rustc_const_eval/src/interpret/cast.rs b/compiler/rustc_const_eval/src/interpret/cast.rs index 49559059265..ef3e96784ce 100644 --- a/compiler/rustc_const_eval/src/interpret/cast.rs +++ b/compiler/rustc_const_eval/src/interpret/cast.rs @@ -83,7 +83,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { ty::FnDef(def_id, args) => { let instance = ty::Instance::resolve_for_fn_ptr( *self.tcx, - self.param_env, + self.typing_env, def_id, args, ) @@ -238,7 +238,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let scalar = src.to_scalar(); let ptr = scalar.to_pointer(self)?; match ptr.into_pointer_or_addr() { - Ok(ptr) => M::expose_ptr(self, ptr)?, + Ok(ptr) => M::expose_provenance(self, ptr.provenance)?, Err(_) => {} // Do nothing, exposing an invalid pointer (`None` provenance) is a NOP. }; interp_ok(ImmTy::from_scalar( @@ -384,7 +384,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { ) -> InterpResult<'tcx> { // A<Struct> -> A<Trait> conversion let (src_pointee_ty, dest_pointee_ty) = - self.tcx.struct_lockstep_tails_for_codegen(source_ty, cast_ty, self.param_env); + self.tcx.struct_lockstep_tails_for_codegen(source_ty, cast_ty, self.typing_env); match (src_pointee_ty.kind(), dest_pointee_ty.kind()) { (&ty::Array(_, length), &ty::Slice(_)) => { diff --git a/compiler/rustc_const_eval/src/interpret/discriminant.rs b/compiler/rustc_const_eval/src/interpret/discriminant.rs index f94d0cbb42b..2f0b1cb6d1e 100644 --- a/compiler/rustc_const_eval/src/interpret/discriminant.rs +++ b/compiler/rustc_const_eval/src/interpret/discriminant.rs @@ -1,7 +1,7 @@ //! Functions for reading and writing discriminants of multi-variant layouts (enums and coroutines). use rustc_abi::{self as abi, TagEncoding, VariantIdx, Variants}; -use rustc_middle::ty::layout::{LayoutOf, PrimitiveExt}; +use rustc_middle::ty::layout::{LayoutOf, PrimitiveExt, TyAndLayout}; use rustc_middle::ty::{self, CoroutineArgsExt, ScalarInt, Ty}; use rustc_middle::{mir, span_bug}; use tracing::{instrument, trace}; @@ -21,17 +21,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { variant_index: VariantIdx, dest: &impl Writeable<'tcx, M::Provenance>, ) -> InterpResult<'tcx> { - // Layout computation excludes uninhabited variants from consideration - // therefore there's no way to represent those variants in the given layout. - // Essentially, uninhabited variants do not have a tag that corresponds to their - // discriminant, so we cannot do anything here. - // When evaluating we will always error before even getting here, but ConstProp 'executes' - // dead code, so we cannot ICE here. - if dest.layout().for_variant(self, variant_index).is_uninhabited() { - throw_ub!(UninhabitedEnumVariantWritten(variant_index)) - } - - match self.tag_for_variant(dest.layout().ty, variant_index)? { + match self.tag_for_variant(dest.layout(), variant_index)? { Some((tag, tag_field)) => { // No need to validate that the discriminant here because the // `TyAndLayout::for_variant()` call earlier already checks the @@ -54,7 +44,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { } } - /// Read discriminant, return the runtime value as well as the variant index. + /// Read discriminant, return the variant index. /// Can also legally be called on non-enums (e.g. through the discriminant_value intrinsic)! /// /// Will never return an uninhabited variant. @@ -75,21 +65,17 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // We use "tag" to refer to how the discriminant is encoded in memory, which can be either // straight-forward (`TagEncoding::Direct`) or with a niche (`TagEncoding::Niche`). let (tag_scalar_layout, tag_encoding, tag_field) = match op.layout().variants { + Variants::Empty => { + throw_ub!(UninhabitedEnumVariantRead(None)); + } Variants::Single { index } => { - // Do some extra checks on enums. - if ty.is_enum() { - // Hilariously, `Single` is used even for 0-variant enums. - // (See https://github.com/rust-lang/rust/issues/89765). - if matches!(ty.kind(), ty::Adt(def, ..) if def.variants().is_empty()) { - throw_ub!(UninhabitedEnumVariantRead(index)) - } + if op.layout().is_uninhabited() { // For consistency with `write_discriminant`, and to make sure that // `project_downcast` cannot fail due to strange layouts, we declare immediate UB - // for uninhabited variants. - if op.layout().for_variant(self, index).is_uninhabited() { - throw_ub!(UninhabitedEnumVariantRead(index)) - } + // for uninhabited enums. + throw_ub!(UninhabitedEnumVariantRead(Some(index))); } + // Since the type is inhabited, there must be an index. return interp_ok(index); } Variants::Multiple { tag, ref tag_encoding, tag_field, .. } => { @@ -188,6 +174,11 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let variants = ty.ty_adt_def().expect("tagged layout for non adt").variants(); assert!(variant_index < variants.next_index()); + if variant_index == untagged_variant { + // The untagged variant can be in the niche range, but even then it + // is not a valid encoding. + throw_ub!(InvalidTag(Scalar::from_uint(tag_bits, tag_layout.size))) + } variant_index } else { untagged_variant @@ -204,11 +195,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // `uninhabited_enum_branching` MIR pass. It also ensures consistency with // `write_discriminant`. if op.layout().for_variant(self, index).is_uninhabited() { - throw_ub!(UninhabitedEnumVariantRead(index)) + throw_ub!(UninhabitedEnumVariantRead(Some(index))) } interp_ok(index) } + /// Read discriminant, return the user-visible discriminant. + /// Can also legally be called on non-enums (e.g. through the discriminant_value intrinsic)! pub fn discriminant_for_variant( &self, ty: Ty<'tcx>, @@ -236,10 +229,19 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { /// given field index. pub(crate) fn tag_for_variant( &self, - ty: Ty<'tcx>, + layout: TyAndLayout<'tcx>, variant_index: VariantIdx, ) -> InterpResult<'tcx, Option<(ScalarInt, usize)>> { - match self.layout_of(ty)?.variants { + // Layout computation excludes uninhabited variants from consideration. + // Therefore, there's no way to represent those variants in the given layout. + // Essentially, uninhabited variants do not have a tag that corresponds to their + // discriminant, so we have to bail out here. + if layout.for_variant(self, variant_index).is_uninhabited() { + throw_ub!(UninhabitedEnumVariantWritten(variant_index)) + } + + match layout.variants { + abi::Variants::Empty => unreachable!("we already handled uninhabited types"), abi::Variants::Single { .. } => { // The tag of a `Single` enum is like the tag of the niched // variant: there's no tag as the discriminant is encoded @@ -260,7 +262,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // raw discriminants for enums are isize or bigger during // their computation, but the in-memory tag is the smallest possible // representation - let discr = self.discriminant_for_variant(ty, variant_index)?; + let discr = self.discriminant_for_variant(layout.ty, variant_index)?; let discr_size = discr.layout.size; let discr_val = discr.to_scalar().to_bits(discr_size)?; let tag_size = tag_layout.size(self); @@ -286,11 +288,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { .. } => { assert!(variant_index != untagged_variant); + // We checked that this variant is inhabited, so it must be in the niche range. + assert!( + niche_variants.contains(&variant_index), + "invalid variant index for this enum" + ); let variants_start = niche_variants.start().as_u32(); - let variant_index_relative = variant_index - .as_u32() - .checked_sub(variants_start) - .expect("overflow computing relative variant idx"); + let variant_index_relative = variant_index.as_u32().strict_sub(variants_start); // We need to use machine arithmetic when taking into account `niche_start`: // tag_val = variant_index_relative + niche_start_val let tag_layout = self.layout_of(tag_layout.primitive().to_int_ty(*self.tcx))?; diff --git a/compiler/rustc_const_eval/src/interpret/eval_context.rs b/compiler/rustc_const_eval/src/interpret/eval_context.rs index ff6d5b28b3b..95a72d3cbc1 100644 --- a/compiler/rustc_const_eval/src/interpret/eval_context.rs +++ b/compiler/rustc_const_eval/src/interpret/eval_context.rs @@ -1,18 +1,18 @@ +use std::assert_matches::debug_assert_matches; + use either::{Left, Right}; use rustc_abi::{Align, HasDataLayout, Size, TargetDataLayout}; use rustc_errors::DiagCtxtHandle; use rustc_hir::def_id::DefId; use rustc_infer::infer::TyCtxtInferExt; use rustc_infer::infer::at::ToTrace; -use rustc_infer::traits::{ObligationCause, Reveal}; +use rustc_infer::traits::ObligationCause; use rustc_middle::mir::interpret::{ErrorHandled, InvalidMetaKind, ReportedErrorInfo}; use rustc_middle::query::TyCtxtAt; use rustc_middle::ty::layout::{ self, FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers, TyAndLayout, }; -use rustc_middle::ty::{ - self, GenericArgsRef, ParamEnv, Ty, TyCtxt, TypeFoldable, TypingMode, Variance, -}; +use rustc_middle::ty::{self, GenericArgsRef, Ty, TyCtxt, TypeFoldable, TypingEnv, Variance}; use rustc_middle::{mir, span_bug}; use rustc_session::Limit; use rustc_span::Span; @@ -38,8 +38,9 @@ pub struct InterpCx<'tcx, M: Machine<'tcx>> { /// we are evaluating (if this is CTFE). pub tcx: TyCtxtAt<'tcx>, - /// Bounds in scope for polymorphic evaluations. - pub(crate) param_env: ty::ParamEnv<'tcx>, + /// The current context in case we're evaluating in a + /// polymorphic context. This always uses `ty::TypingMode::PostAnalysis`. + pub(super) typing_env: ty::TypingEnv<'tcx>, /// The virtual memory system. pub memory: Memory<'tcx, M>, @@ -65,12 +66,12 @@ where } } -impl<'tcx, M> layout::HasParamEnv<'tcx> for InterpCx<'tcx, M> +impl<'tcx, M> layout::HasTypingEnv<'tcx> for InterpCx<'tcx, M> where M: Machine<'tcx>, { - fn param_env(&self) -> ty::ParamEnv<'tcx> { - self.param_env + fn typing_env(&self) -> ty::TypingEnv<'tcx> { + self.typing_env } } @@ -116,8 +117,7 @@ impl<'tcx, M: Machine<'tcx>> FnAbiOfHelpers<'tcx> for InterpCx<'tcx, M> { /// This test should be symmetric, as it is primarily about layout compatibility. pub(super) fn mir_assign_valid_types<'tcx>( tcx: TyCtxt<'tcx>, - typing_mode: TypingMode<'tcx>, - param_env: ParamEnv<'tcx>, + typing_env: TypingEnv<'tcx>, src: TyAndLayout<'tcx>, dest: TyAndLayout<'tcx>, ) -> bool { @@ -125,7 +125,7 @@ pub(super) fn mir_assign_valid_types<'tcx>( // all normal lifetimes are erased, higher-ranked types with their // late-bound lifetimes are still around and can lead to type // differences. - if util::relate_types(tcx, typing_mode, param_env, Variance::Covariant, src.ty, dest.ty) { + if util::relate_types(tcx, typing_env, Variance::Covariant, src.ty, dest.ty) { // Make sure the layout is equal, too -- just to be safe. Miri really // needs layout equality. For performance reason we skip this check when // the types are equal. Equal types *can* have different layouts when @@ -145,8 +145,7 @@ pub(super) fn mir_assign_valid_types<'tcx>( #[cfg_attr(not(debug_assertions), inline(always))] pub(super) fn from_known_layout<'tcx>( tcx: TyCtxtAt<'tcx>, - typing_mode: TypingMode<'tcx>, - param_env: ParamEnv<'tcx>, + typing_env: TypingEnv<'tcx>, known_layout: Option<TyAndLayout<'tcx>>, compute: impl FnOnce() -> InterpResult<'tcx, TyAndLayout<'tcx>>, ) -> InterpResult<'tcx, TyAndLayout<'tcx>> { @@ -155,13 +154,7 @@ pub(super) fn from_known_layout<'tcx>( Some(known_layout) => { if cfg!(debug_assertions) { let check_layout = compute()?; - if !mir_assign_valid_types( - tcx.tcx, - typing_mode, - param_env, - check_layout, - known_layout, - ) { + if !mir_assign_valid_types(tcx.tcx, typing_env, check_layout, known_layout) { span_bug!( tcx.span, "expected type differs from actual type.\nexpected: {}\nactual: {}", @@ -199,23 +192,23 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { pub fn new( tcx: TyCtxt<'tcx>, root_span: Span, - param_env: ty::ParamEnv<'tcx>, + typing_env: ty::TypingEnv<'tcx>, machine: M, ) -> Self { + // Const eval always happens in post analysis mode in order to be able to use the hidden types of + // opaque types. This is needed for trivial things like `size_of`, but also for using associated + // types that are not specified in the opaque type. We also use MIR bodies whose opaque types have + // already been revealed, so we'd be able to at least partially observe the hidden types anyways. + debug_assert_matches!(typing_env.typing_mode, ty::TypingMode::PostAnalysis); InterpCx { machine, tcx: tcx.at(root_span), - param_env, + typing_env, memory: Memory::new(), recursion_limit: tcx.recursion_limit(), } } - pub fn typing_mode(&self) -> TypingMode<'tcx> { - debug_assert_eq!(self.param_env.reveal(), Reveal::All); - TypingMode::PostAnalysis - } - /// Returns the span of the currently executed statement/terminator. /// This is the span typically used for error reporting. #[inline(always)] @@ -258,7 +251,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { #[inline] pub fn type_is_freeze(&self, ty: Ty<'tcx>) -> bool { - ty.is_freeze(*self.tcx, self.param_env) + ty.is_freeze(*self.tcx, self.typing_env) } pub fn load_mir( @@ -275,7 +268,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { }; // do not continue if typeck errors occurred (can only occur in local crate) if let Some(err) = body.tainted_by_errors { - throw_inval!(AlreadyReported(ReportedErrorInfo::tainted_by_errors(err))); + throw_inval!(AlreadyReported(ReportedErrorInfo::non_const_eval_error(err))); } interp_ok(body) } @@ -304,31 +297,33 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { .instance .try_instantiate_mir_and_normalize_erasing_regions( *self.tcx, - self.param_env, + self.typing_env, ty::EarlyBinder::bind(value), ) .map_err(|_| ErrorHandled::TooGeneric(self.cur_span())) } - /// The `args` are assumed to already be in our interpreter "universe" (param_env). + /// The `args` are assumed to already be in our interpreter "universe". pub(super) fn resolve( &self, def: DefId, args: GenericArgsRef<'tcx>, ) -> InterpResult<'tcx, ty::Instance<'tcx>> { trace!("resolve: {:?}, {:#?}", def, args); - trace!("param_env: {:#?}", self.param_env); + trace!("typing_env: {:#?}", self.typing_env); trace!("args: {:#?}", args); - match ty::Instance::try_resolve(*self.tcx, self.param_env, def, args) { + match ty::Instance::try_resolve(*self.tcx, self.typing_env, def, args) { Ok(Some(instance)) => interp_ok(instance), Ok(None) => throw_inval!(TooGeneric), // FIXME(eddyb) this could be a bit more specific than `AlreadyReported`. - Err(error_reported) => throw_inval!(AlreadyReported(error_reported.into())), + Err(error_guaranteed) => throw_inval!(AlreadyReported( + ReportedErrorInfo::non_const_eval_error(error_guaranteed) + )), } } - /// Check if the two things are equal in the current param_env, using an infctx to get proper + /// Check if the two things are equal in the current param_env, using an infcx to get proper /// equality checks. #[instrument(level = "trace", skip(self), ret)] pub(super) fn eq_in_param_env<T>(&self, a: T, b: T) -> bool @@ -340,14 +335,14 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { return true; } // Slow path: spin up an inference context to check if these traits are sufficiently equal. - let infcx = self.tcx.infer_ctxt().build(self.typing_mode()); + let (infcx, param_env) = self.tcx.infer_ctxt().build_with_typing_env(self.typing_env); let ocx = ObligationCtxt::new(&infcx); let cause = ObligationCause::dummy_with_span(self.cur_span()); // equate the two trait refs after normalization - let a = ocx.normalize(&cause, self.param_env, a); - let b = ocx.normalize(&cause, self.param_env, b); + let a = ocx.normalize(&cause, param_env, a); + let b = ocx.normalize(&cause, param_env, b); - if let Err(terr) = ocx.eq(&cause, self.param_env, a, b) { + if let Err(terr) = ocx.eq(&cause, param_env, a, b) { trace!(?terr); return false; } @@ -572,10 +567,10 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let val = if self.tcx.is_static(gid.instance.def_id()) { let alloc_id = self.tcx.reserve_and_set_static_alloc(gid.instance.def_id()); - let ty = instance.ty(self.tcx.tcx, self.param_env); + let ty = instance.ty(self.tcx.tcx, self.typing_env); mir::ConstAlloc { alloc_id, ty } } else { - self.ctfe_query(|tcx| tcx.eval_to_allocation_raw(self.param_env.and(gid)))? + self.ctfe_query(|tcx| tcx.eval_to_allocation_raw(self.typing_env.as_query_input(gid)))? }; self.raw_const_to_mplace(val) } @@ -587,15 +582,15 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { layout: Option<TyAndLayout<'tcx>>, ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> { M::eval_mir_constant(self, *val, span, layout, |ecx, val, span, layout| { - let const_val = val.eval(*ecx.tcx, ecx.param_env, span).map_err(|err| { + let const_val = val.eval(*ecx.tcx, ecx.typing_env, span).map_err(|err| { if M::ALL_CONSTS_ARE_PRECHECKED { match err { ErrorHandled::TooGeneric(..) => {}, ErrorHandled::Reported(reported, span) => { - if reported.is_tainted_by_errors() { - // const-eval will return "tainted" errors if e.g. the layout cannot - // be computed as the type references non-existing names. - // See <https://github.com/rust-lang/rust/issues/124348>. + if reported.is_allowed_in_infallible() { + // These errors can just sometimes happen, even when the expression + // is nominally "infallible", e.g. when running out of memory + // or when some layout could not be computed. } else { // Looks like the const is not captured by `required_consts`, that's bad. span_bug!(span, "interpret const eval failure of {val:?} which is not in required_consts"); diff --git a/compiler/rustc_const_eval/src/interpret/intern.rs b/compiler/rustc_const_eval/src/interpret/intern.rs index 7a1b92601a4..0cbb3b157f3 100644 --- a/compiler/rustc_const_eval/src/interpret/intern.rs +++ b/compiler/rustc_const_eval/src/interpret/intern.rs @@ -165,7 +165,7 @@ pub fn intern_const_alloc_recursive<'tcx, M: CompileTimeMachine<'tcx, const_eval InternKind::Static(Mutability::Not) => { ( // Outermost allocation is mutable if `!Freeze`. - if ret.layout.ty.is_freeze(*ecx.tcx, ecx.param_env) { + if ret.layout.ty.is_freeze(*ecx.tcx, ecx.typing_env) { Mutability::Not } else { Mutability::Mut diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs index c7a56a80e81..1af8438534f 100644 --- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs +++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs @@ -11,7 +11,7 @@ use rustc_middle::mir::{self, BinOp, ConstValue, NonDivergingIntrinsic}; use rustc_middle::ty::layout::{LayoutOf as _, TyAndLayout, ValidityRequirement}; use rustc_middle::ty::{GenericArgsRef, Ty, TyCtxt}; use rustc_middle::{bug, ty}; -use rustc_span::symbol::{Symbol, sym}; +use rustc_span::{Symbol, sym}; use tracing::trace; use super::memory::MemoryKind; @@ -34,7 +34,7 @@ pub(crate) fn alloc_type_name<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> ConstAll /// inside an `InterpCx` and instead have their value computed directly from rustc internal info. pub(crate) fn eval_nullary_intrinsic<'tcx>( tcx: TyCtxt<'tcx>, - param_env: ty::ParamEnv<'tcx>, + typing_env: ty::TypingEnv<'tcx>, def_id: DefId, args: GenericArgsRef<'tcx>, ) -> InterpResult<'tcx, ConstValue<'tcx>> { @@ -48,11 +48,13 @@ pub(crate) fn eval_nullary_intrinsic<'tcx>( } sym::needs_drop => { ensure_monomorphic_enough(tcx, tp_ty)?; - ConstValue::from_bool(tp_ty.needs_drop(tcx, param_env)) + ConstValue::from_bool(tp_ty.needs_drop(tcx, typing_env)) } sym::pref_align_of => { // Correctly handles non-monomorphic calls, so there is no need for ensure_monomorphic_enough. - let layout = tcx.layout_of(param_env.and(tp_ty)).map_err(|e| err_inval!(Layout(*e)))?; + let layout = tcx + .layout_of(typing_env.as_query_input(tp_ty)) + .map_err(|e| err_inval!(Layout(*e)))?; ConstValue::from_target_usize(layout.align.pref.bytes(), &tcx) } sym::type_id => { @@ -149,8 +151,8 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { sym::type_name => Ty::new_static_str(self.tcx.tcx), _ => bug!(), }; - let val = - self.ctfe_query(|tcx| tcx.const_eval_global_id(self.param_env, gid, tcx.span))?; + let val = self + .ctfe_query(|tcx| tcx.const_eval_global_id(self.typing_env, gid, tcx.span))?; let val = self.const_val_to_op(val, ty, Some(dest.layout))?; self.copy_op(&val, dest)?; } @@ -355,7 +357,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let should_panic = !self .tcx - .check_validity_requirement((requirement, self.param_env.and(ty))) + .check_validity_requirement((requirement, self.typing_env.as_query_input(ty))) .map_err(|_| err_inval!(TooGeneric))?; if should_panic { diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs index dbe09d55b2d..9ac2a024ccf 100644 --- a/compiler/rustc_const_eval/src/interpret/machine.rs +++ b/compiler/rustc_const_eval/src/interpret/machine.rs @@ -327,11 +327,11 @@ pub trait Machine<'tcx>: Sized { addr: u64, ) -> InterpResult<'tcx, Pointer<Option<Self::Provenance>>>; - /// Marks a pointer as exposed, allowing it's provenance + /// Marks a pointer as exposed, allowing its provenance /// to be recovered. "Pointer-to-int cast" - fn expose_ptr( - ecx: &mut InterpCx<'tcx, Self>, - ptr: Pointer<Self::Provenance>, + fn expose_provenance( + ecx: &InterpCx<'tcx, Self>, + provenance: Self::Provenance, ) -> InterpResult<'tcx>; /// Convert a pointer with provenance into an allocation-offset pair and extra provenance info. @@ -540,10 +540,14 @@ pub trait Machine<'tcx>: Sized { interp_ok(ReturnAction::Normal) } - /// Called immediately after an "immediate" local variable is read + /// Called immediately after an "immediate" local variable is read in a given frame /// (i.e., this is called for reads that do not end up accessing addressable memory). #[inline(always)] - fn after_local_read(_ecx: &InterpCx<'tcx, Self>, _local: mir::Local) -> InterpResult<'tcx> { + fn after_local_read( + _ecx: &InterpCx<'tcx, Self>, + _frame: &Frame<'tcx, Self::Provenance, Self::FrameExtra>, + _local: mir::Local, + ) -> InterpResult<'tcx> { interp_ok(()) } diff --git a/compiler/rustc_const_eval/src/interpret/memory.rs b/compiler/rustc_const_eval/src/interpret/memory.rs index 1ad8ffa4b53..027ba9644cb 100644 --- a/compiler/rustc_const_eval/src/interpret/memory.rs +++ b/compiler/rustc_const_eval/src/interpret/memory.rs @@ -14,10 +14,9 @@ use std::{fmt, mem, ptr}; use rustc_abi::{Align, HasDataLayout, Size}; use rustc_ast::Mutability; use rustc_data_structures::fx::{FxHashSet, FxIndexMap}; -use rustc_hir::def::DefKind; use rustc_middle::bug; use rustc_middle::mir::display_allocation; -use rustc_middle::ty::{self, Instance, ParamEnv, Ty, TyCtxt}; +use rustc_middle::ty::{self, Instance, Ty, TyCtxt}; use tracing::{debug, instrument, trace}; use super::{ @@ -72,6 +71,21 @@ pub enum AllocKind { Dead, } +/// Metadata about an `AllocId`. +#[derive(Copy, Clone, PartialEq, Debug)] +pub struct AllocInfo { + pub size: Size, + pub align: Align, + pub kind: AllocKind, + pub mutbl: Mutability, +} + +impl AllocInfo { + fn new(size: Size, align: Align, kind: AllocKind, mutbl: Mutability) -> Self { + Self { size, align, kind, mutbl } + } +} + /// The value of a function pointer. #[derive(Debug, Copy, Clone)] pub enum FnVal<'tcx, Other> { @@ -524,17 +538,22 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { match self.ptr_try_get_alloc_id(ptr, 0) { Err(addr) => is_offset_misaligned(addr, align), Ok((alloc_id, offset, _prov)) => { - let (_size, alloc_align, kind) = self.get_alloc_info(alloc_id); - if let Some(misalign) = - M::alignment_check(self, alloc_id, alloc_align, kind, offset, align) - { + let alloc_info = self.get_alloc_info(alloc_id); + if let Some(misalign) = M::alignment_check( + self, + alloc_id, + alloc_info.align, + alloc_info.kind, + offset, + align, + ) { Some(misalign) } else if M::Provenance::OFFSET_IS_ADDR { is_offset_misaligned(ptr.addr().bytes(), align) } else { // Check allocation alignment and offset alignment. - if alloc_align.bytes() < align.bytes() { - Some(Misalignment { has: alloc_align, required: align }) + if alloc_info.align.bytes() < align.bytes() { + Some(Misalignment { has: alloc_info.align, required: align }) } else { is_offset_misaligned(offset.bytes(), align) } @@ -818,82 +837,45 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { /// Obtain the size and alignment of an allocation, even if that allocation has /// been deallocated. - pub fn get_alloc_info(&self, id: AllocId) -> (Size, Align, AllocKind) { + pub fn get_alloc_info(&self, id: AllocId) -> AllocInfo { // # Regular allocations // Don't use `self.get_raw` here as that will // a) cause cycles in case `id` refers to a static // b) duplicate a global's allocation in miri if let Some((_, alloc)) = self.memory.alloc_map.get(id) { - return (alloc.size(), alloc.align, AllocKind::LiveData); + return AllocInfo::new( + alloc.size(), + alloc.align, + AllocKind::LiveData, + alloc.mutability, + ); } // # Function pointers // (both global from `alloc_map` and local from `extra_fn_ptr_map`) if self.get_fn_alloc(id).is_some() { - return (Size::ZERO, Align::ONE, AllocKind::Function); + return AllocInfo::new(Size::ZERO, Align::ONE, AllocKind::Function, Mutability::Not); } - // # Statics - // Can't do this in the match argument, we may get cycle errors since the lock would - // be held throughout the match. - match self.tcx.try_get_global_alloc(id) { - Some(GlobalAlloc::Static(def_id)) => { - // Thread-local statics do not have a constant address. They *must* be accessed via - // `ThreadLocalRef`; we can never have a pointer to them as a regular constant value. - assert!(!self.tcx.is_thread_local_static(def_id)); - - let DefKind::Static { nested, .. } = self.tcx.def_kind(def_id) else { - bug!("GlobalAlloc::Static is not a static") - }; - - let (size, align) = if nested { - // Nested anonymous statics are untyped, so let's get their - // size and alignment from the allocation itself. This always - // succeeds, as the query is fed at DefId creation time, so no - // evaluation actually occurs. - let alloc = self.tcx.eval_static_initializer(def_id).unwrap(); - (alloc.0.size(), alloc.0.align) - } else { - // Use size and align of the type for everything else. We need - // to do that to - // * avoid cycle errors in case of self-referential statics, - // * be able to get information on extern statics. - let ty = self - .tcx - .type_of(def_id) - .no_bound_vars() - .expect("statics should not have generic parameters"); - let layout = self.tcx.layout_of(ParamEnv::empty().and(ty)).unwrap(); - assert!(layout.is_sized()); - (layout.size, layout.align.abi) - }; - (size, align, AllocKind::LiveData) - } - Some(GlobalAlloc::Memory(alloc)) => { - // Need to duplicate the logic here, because the global allocations have - // different associated types than the interpreter-local ones. - let alloc = alloc.inner(); - (alloc.size(), alloc.align, AllocKind::LiveData) - } - Some(GlobalAlloc::Function { .. }) => { - bug!("We already checked function pointers above") - } - Some(GlobalAlloc::VTable(..)) => { - // No data to be accessed here. But vtables are pointer-aligned. - return (Size::ZERO, self.tcx.data_layout.pointer_align.abi, AllocKind::VTable); - } - // The rest must be dead. - None => { - // Deallocated pointers are allowed, we should be able to find - // them in the map. - let (size, align) = *self - .memory - .dead_alloc_map - .get(&id) - .expect("deallocated pointers should all be recorded in `dead_alloc_map`"); - (size, align, AllocKind::Dead) - } + // # Global allocations + if let Some(global_alloc) = self.tcx.try_get_global_alloc(id) { + let (size, align) = global_alloc.size_and_align(*self.tcx, self.typing_env); + let mutbl = global_alloc.mutability(*self.tcx, self.typing_env); + let kind = match global_alloc { + GlobalAlloc::Static { .. } | GlobalAlloc::Memory { .. } => AllocKind::LiveData, + GlobalAlloc::Function { .. } => bug!("We already checked function pointers above"), + GlobalAlloc::VTable { .. } => AllocKind::VTable, + }; + return AllocInfo::new(size, align, kind, mutbl); } + + // # Dead pointers + let (size, align) = *self + .memory + .dead_alloc_map + .get(&id) + .expect("deallocated pointers should all be recorded in `dead_alloc_map`"); + AllocInfo::new(size, align, AllocKind::Dead, Mutability::Not) } /// Obtain the size and alignment of a *live* allocation. @@ -902,11 +884,11 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { id: AllocId, msg: CheckInAllocMsg, ) -> InterpResult<'tcx, (Size, Align)> { - let (size, align, kind) = self.get_alloc_info(id); - if matches!(kind, AllocKind::Dead) { + let info = self.get_alloc_info(id); + if matches!(info.kind, AllocKind::Dead) { throw_ub!(PointerUseAfterFree(id, msg)) } - interp_ok((size, align)) + interp_ok((info.size, info.align)) } fn get_fn_alloc(&self, id: AllocId) -> Option<FnVal<'tcx, M::ExtraFnVal>> { @@ -962,6 +944,52 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { interp_ok(()) } + /// Handle the effect an FFI call might have on the state of allocations. + /// This overapproximates the modifications which external code might make to memory: + /// We set all reachable allocations as initialized, mark all provenances as exposed + /// and overwrite them with `Provenance::WILDCARD`. + pub fn prepare_for_native_call( + &mut self, + id: AllocId, + initial_prov: M::Provenance, + ) -> InterpResult<'tcx> { + // Expose provenance of the root allocation. + M::expose_provenance(self, initial_prov)?; + + let mut done = FxHashSet::default(); + let mut todo = vec![id]; + while let Some(id) = todo.pop() { + if !done.insert(id) { + // We already saw this allocation before, don't process it again. + continue; + } + let info = self.get_alloc_info(id); + + // If there is no data behind this pointer, skip this. + if !matches!(info.kind, AllocKind::LiveData) { + continue; + } + + // Expose all provenances in this allocation, and add them to `todo`. + let alloc = self.get_alloc_raw(id)?; + for prov in alloc.provenance().provenances() { + M::expose_provenance(self, prov)?; + if let Some(id) = prov.get_alloc_id() { + todo.push(id); + } + } + + // Prepare for possible write from native code if mutable. + if info.mutbl.is_mut() { + self.get_alloc_raw_mut(id)? + .0 + .prepare_for_native_write() + .map_err(|e| e.to_interp_error(id))?; + } + } + interp_ok(()) + } + /// Create a lazy debug printer that prints the given allocation and all allocations it points /// to, recursively. #[must_use] @@ -1458,7 +1486,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let ptr = scalar.to_pointer(self)?; match self.ptr_try_get_alloc_id(ptr, 0) { Ok((alloc_id, offset, _)) => { - let (size, _align, _kind) = self.get_alloc_info(alloc_id); + let size = self.get_alloc_info(alloc_id).size; // If the pointer is out-of-bounds, it may be null. // Note that one-past-the-end (offset == size) is still inbounds, and never null. offset > size diff --git a/compiler/rustc_const_eval/src/interpret/mod.rs b/compiler/rustc_const_eval/src/interpret/mod.rs index 5e84626f77e..f5792aba207 100644 --- a/compiler/rustc_const_eval/src/interpret/mod.rs +++ b/compiler/rustc_const_eval/src/interpret/mod.rs @@ -31,7 +31,7 @@ pub use self::intern::{ }; pub(crate) use self::intrinsics::eval_nullary_intrinsic; pub use self::machine::{AllocMap, Machine, MayLeak, ReturnAction, compile_time_machine}; -pub use self::memory::{AllocKind, AllocRef, AllocRefMut, FnVal, Memory, MemoryKind}; +pub use self::memory::{AllocInfo, AllocKind, AllocRef, AllocRefMut, FnVal, Memory, MemoryKind}; use self::operand::Operand; pub use self::operand::{ImmTy, Immediate, OpTy}; pub use self::place::{MPlaceTy, MemPlaceMeta, PlaceTy, Writeable}; diff --git a/compiler/rustc_const_eval/src/interpret/operand.rs b/compiler/rustc_const_eval/src/interpret/operand.rs index a130ae89bcb..b861ffb6110 100644 --- a/compiler/rustc_const_eval/src/interpret/operand.rs +++ b/compiler/rustc_const_eval/src/interpret/operand.rs @@ -8,16 +8,16 @@ use rustc_abi as abi; use rustc_abi::{BackendRepr, HasDataLayout, Size}; use rustc_hir::def::Namespace; use rustc_middle::mir::interpret::ScalarSizeMismatch; -use rustc_middle::ty::layout::{HasParamEnv, HasTyCtxt, LayoutOf, TyAndLayout}; +use rustc_middle::ty::layout::{HasTyCtxt, HasTypingEnv, LayoutOf, TyAndLayout}; use rustc_middle::ty::print::{FmtPrinter, PrettyPrinter}; use rustc_middle::ty::{ConstInt, ScalarInt, Ty, TyCtxt}; use rustc_middle::{bug, mir, span_bug, ty}; use tracing::trace; use super::{ - CtfeProvenance, InterpCx, InterpResult, MPlaceTy, Machine, MemPlace, MemPlaceMeta, OffsetMode, - PlaceTy, Pointer, Projectable, Provenance, Scalar, alloc_range, err_ub, from_known_layout, - interp_ok, mir_assign_valid_types, throw_ub, + CtfeProvenance, Frame, InterpCx, InterpResult, MPlaceTy, Machine, MemPlace, MemPlaceMeta, + OffsetMode, PlaceTy, Pointer, Projectable, Provenance, Scalar, alloc_range, err_ub, + from_known_layout, interp_ok, mir_assign_valid_types, throw_ub, }; /// An `Immediate` represents a single immediate self-contained Rust value. @@ -297,21 +297,27 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> { #[inline] pub fn from_bool(b: bool, tcx: TyCtxt<'tcx>) -> Self { - let layout = tcx.layout_of(ty::ParamEnv::reveal_all().and(tcx.types.bool)).unwrap(); + // Can use any typing env, since `bool` is always monomorphic. + let layout = tcx + .layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(tcx.types.bool)) + .unwrap(); Self::from_scalar(Scalar::from_bool(b), layout) } #[inline] pub fn from_ordering(c: std::cmp::Ordering, tcx: TyCtxt<'tcx>) -> Self { + // Can use any typing env, since `Ordering` is always monomorphic. let ty = tcx.ty_ordering_enum(None); - let layout = tcx.layout_of(ty::ParamEnv::reveal_all().and(ty)).unwrap(); + let layout = + tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty)).unwrap(); Self::from_scalar(Scalar::from_i8(c as i8), layout) } - pub fn from_pair(a: Self, b: Self, tcx: TyCtxt<'tcx>) -> Self { - let layout = tcx + pub fn from_pair(a: Self, b: Self, cx: &(impl HasTypingEnv<'tcx> + HasTyCtxt<'tcx>)) -> Self { + let layout = cx + .tcx() .layout_of( - ty::ParamEnv::reveal_all().and(Ty::new_tup(tcx, &[a.layout.ty, b.layout.ty])), + cx.typing_env().as_query_input(Ty::new_tup(cx.tcx(), &[a.layout.ty, b.layout.ty])), ) .unwrap(); Self::from_scalar_pair(a.to_scalar(), b.to_scalar(), layout) @@ -341,7 +347,7 @@ impl<'tcx, Prov: Provenance> ImmTy<'tcx, Prov> { #[inline] #[cfg_attr(debug_assertions, track_caller)] // only in debug builds due to perf (see #98980) - pub fn to_pair(self, cx: &(impl HasTyCtxt<'tcx> + HasParamEnv<'tcx>)) -> (Self, Self) { + pub fn to_pair(self, cx: &(impl HasTyCtxt<'tcx> + HasTypingEnv<'tcx>)) -> (Self, Self) { let layout = self.layout; let (val0, val1) = self.to_scalar_pair(); ( @@ -702,23 +708,32 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { interp_ok(str) } - /// Read from a local of the current frame. + /// Read from a local of the current frame. Convenience method for [`InterpCx::local_at_frame_to_op`]. + pub fn local_to_op( + &self, + local: mir::Local, + layout: Option<TyAndLayout<'tcx>>, + ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> { + self.local_at_frame_to_op(self.frame(), local, layout) + } + + /// Read from a local of a given frame. /// Will not access memory, instead an indirect `Operand` is returned. /// - /// This is public because it is used by [priroda](https://github.com/oli-obk/priroda) to get an - /// OpTy from a local. - pub fn local_to_op( + /// This is public because it is used by [Aquascope](https://github.com/cognitive-engineering-lab/aquascope/) + /// to get an OpTy from a local. + pub fn local_at_frame_to_op( &self, + frame: &Frame<'tcx, M::Provenance, M::FrameExtra>, local: mir::Local, layout: Option<TyAndLayout<'tcx>>, ) -> InterpResult<'tcx, OpTy<'tcx, M::Provenance>> { - let frame = self.frame(); let layout = self.layout_of_local(frame, local, layout)?; let op = *frame.locals[local].access()?; if matches!(op, Operand::Immediate(_)) { assert!(!layout.is_unsized()); } - M::after_local_read(self, local)?; + M::after_local_read(self, frame, local)?; interp_ok(OpTy { op, layout }) } @@ -773,8 +788,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { )?; if !mir_assign_valid_types( *self.tcx, - self.typing_mode(), - self.param_env, + self.typing_env(), self.layout_of(normalized_place_ty)?, op.layout, ) { @@ -833,9 +847,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { }) }; let layout = - from_known_layout(self.tcx, self.typing_mode(), self.param_env, layout, || { - self.layout_of(ty).into() - })?; + from_known_layout(self.tcx, self.typing_env(), layout, || self.layout_of(ty).into())?; let imm = match val_val { mir::ConstValue::Indirect { alloc_id, offset } => { // This is const data, no mutation allowed. diff --git a/compiler/rustc_const_eval/src/interpret/operator.rs b/compiler/rustc_const_eval/src/interpret/operator.rs index fbc85d37953..5fa632fc57a 100644 --- a/compiler/rustc_const_eval/src/interpret/operator.rs +++ b/compiler/rustc_const_eval/src/interpret/operator.rs @@ -6,7 +6,7 @@ use rustc_middle::mir::interpret::{InterpResult, PointerArithmetic, Scalar}; use rustc_middle::ty::layout::{LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, FloatTy, ScalarInt, Ty}; use rustc_middle::{bug, mir, span_bug}; -use rustc_span::symbol::sym; +use rustc_span::sym; use tracing::trace; use super::{ImmTy, InterpCx, Machine, MemPlaceMeta, interp_ok, throw_ub}; @@ -222,7 +222,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let res = ImmTy::from_scalar_int(result, left.layout); return interp_ok(if with_overflow { let overflow = ImmTy::from_bool(overflow, *self.tcx); - ImmTy::from_pair(res, overflow, *self.tcx) + ImmTy::from_pair(res, overflow, self) } else { res }); @@ -279,7 +279,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let res = ImmTy::from_scalar_int(result, left.layout); if with_overflow { let overflow = ImmTy::from_bool(overflow, *self.tcx); - ImmTy::from_pair(res, overflow, *self.tcx) + ImmTy::from_pair(res, overflow, self) } else { res } @@ -533,7 +533,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { } OffsetOf(fields) => { let val = - self.tcx.offset_of_subfield(self.param_env, layout, fields.iter()).bytes(); + self.tcx.offset_of_subfield(self.typing_env, layout, fields.iter()).bytes(); ImmTy::from_uint(val, usize_layout()) } UbChecks => ImmTy::from_bool(M::ub_checks(self)?, *self.tcx), diff --git a/compiler/rustc_const_eval/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs index cc8d1db6cfb..810e9356b26 100644 --- a/compiler/rustc_const_eval/src/interpret/place.rs +++ b/compiler/rustc_const_eval/src/interpret/place.rs @@ -5,8 +5,7 @@ use std::assert_matches::assert_matches; use either::{Either, Left, Right}; -use rustc_abi::{Align, BackendRepr, HasDataLayout, Size}; -use rustc_ast::Mutability; +use rustc_abi::{BackendRepr, HasDataLayout, Size}; use rustc_middle::ty::Ty; use rustc_middle::ty::layout::{LayoutOf, TyAndLayout}; use rustc_middle::{bug, mir, span_bug}; @@ -540,8 +539,7 @@ where )?; if !mir_assign_valid_types( *self.tcx, - self.typing_mode(), - self.param_env, + self.typing_env, self.layout_of(normalized_place_ty)?, place.layout, ) { @@ -871,13 +869,8 @@ where ) -> InterpResult<'tcx> { // We do NOT compare the types for equality, because well-typed code can // actually "transmute" `&mut T` to `&T` in an assignment without a cast. - let layout_compat = mir_assign_valid_types( - *self.tcx, - self.typing_mode(), - self.param_env, - src.layout(), - dest.layout(), - ); + let layout_compat = + mir_assign_valid_types(*self.tcx, self.typing_env, src.layout(), dest.layout()); if !allow_transmute && !layout_compat { span_bug!( self.cur_span(), @@ -1024,29 +1017,39 @@ where self.allocate_dyn(layout, kind, MemPlaceMeta::None) } - /// Returns a wide MPlace of type `str` to a new 1-aligned allocation. - /// Immutable strings are deduplicated and stored in global memory. - pub fn allocate_str( + /// Allocates a sequence of bytes in the interpreter's memory with alignment 1. + /// This is allocated in immutable global memory and deduplicated. + pub fn allocate_bytes_dedup( + &mut self, + bytes: &[u8], + ) -> InterpResult<'tcx, Pointer<M::Provenance>> { + let salt = M::get_global_alloc_salt(self, None); + let id = self.tcx.allocate_bytes_dedup(bytes, salt); + + // Turn untagged "global" pointers (obtained via `tcx`) into the machine pointer to the allocation. + M::adjust_alloc_root_pointer( + &self, + Pointer::from(id), + M::GLOBAL_KIND.map(MemoryKind::Machine), + ) + } + + /// Allocates a string in the interpreter's memory, returning it as a (wide) place. + /// This is allocated in immutable global memory and deduplicated. + pub fn allocate_str_dedup( &mut self, str: &str, - kind: MemoryKind<M::MemoryKind>, - mutbl: Mutability, ) -> InterpResult<'tcx, MPlaceTy<'tcx, M::Provenance>> { - let tcx = self.tcx.tcx; + let bytes = str.as_bytes(); + let ptr = self.allocate_bytes_dedup(bytes)?; - // Use cache for immutable strings. - let ptr = if mutbl.is_not() { - // Use dedup'd allocation function. - let salt = M::get_global_alloc_salt(self, None); - let id = tcx.allocate_bytes_dedup(str.as_bytes(), salt); + // Create length metadata for the string. + let meta = Scalar::from_target_usize(u64::try_from(bytes.len()).unwrap(), self); - // Turn untagged "global" pointers (obtained via `tcx`) into the machine pointer to the allocation. - M::adjust_alloc_root_pointer(&self, Pointer::from(id), Some(kind))? - } else { - self.allocate_bytes_ptr(str.as_bytes(), Align::ONE, kind, mutbl)? - }; - let meta = Scalar::from_target_usize(u64::try_from(str.len()).unwrap(), self); + // Get layout for Rust's str type. let layout = self.layout_of(self.tcx.types.str_).unwrap(); + + // Combine pointer and metadata into a wide pointer. interp_ok(self.ptr_with_meta_to_mplace( ptr.into(), MemPlaceMeta::Meta(meta), diff --git a/compiler/rustc_const_eval/src/interpret/projection.rs b/compiler/rustc_const_eval/src/interpret/projection.rs index 65a93784e2c..996142d7b03 100644 --- a/compiler/rustc_const_eval/src/interpret/projection.rs +++ b/compiler/rustc_const_eval/src/interpret/projection.rs @@ -325,7 +325,7 @@ where let actual_to = if from_end { if from.checked_add(to).is_none_or(|to| to > len) { // This can only be reached in ConstProp and non-rustc-MIR. - throw_ub!(BoundsCheckFailed { len: len, index: from.saturating_add(to) }); + throw_ub!(BoundsCheckFailed { len, index: from.saturating_add(to) }); } len.checked_sub(to).unwrap() } else { diff --git a/compiler/rustc_const_eval/src/interpret/stack.rs b/compiler/rustc_const_eval/src/interpret/stack.rs index 50c0446b3cd..6512675530a 100644 --- a/compiler/rustc_const_eval/src/interpret/stack.rs +++ b/compiler/rustc_const_eval/src/interpret/stack.rs @@ -10,7 +10,7 @@ use rustc_index::IndexVec; use rustc_middle::ty::layout::{LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, Ty, TyCtxt}; use rustc_middle::{bug, mir}; -use rustc_mir_dataflow::storage::always_storage_live_locals; +use rustc_mir_dataflow::impls::always_storage_live_locals; use rustc_span::Span; use tracing::{info_span, instrument, trace}; @@ -379,7 +379,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { for &const_ in body.required_consts() { let c = self.instantiate_from_current_frame_and_normalize_erasing_regions(const_.const_)?; - c.eval(*self.tcx, self.param_env, const_.span).map_err(|err| { + c.eval(*self.tcx, self.typing_env, const_.span).map_err(|err| { err.emit_note(*self.tcx); err })?; @@ -584,8 +584,10 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { interp_ok(()) } + /// This is public because it is used by [Aquascope](https://github.com/cognitive-engineering-lab/aquascope/) + /// to analyze all the locals in a stack frame. #[inline(always)] - pub(super) fn layout_of_local( + pub fn layout_of_local( &self, frame: &Frame<'tcx, M::Provenance, M::FrameExtra>, local: mir::Local, @@ -596,13 +598,12 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { return interp_ok(layout); } - let layout = - from_known_layout(self.tcx, self.typing_mode(), self.param_env, layout, || { - let local_ty = frame.body.local_decls[local].ty; - let local_ty = - self.instantiate_from_frame_and_normalize_erasing_regions(frame, local_ty)?; - self.layout_of(local_ty).into() - })?; + let layout = from_known_layout(self.tcx, self.typing_env, layout, || { + let local_ty = frame.body.local_decls[local].ty; + let local_ty = + self.instantiate_from_frame_and_normalize_erasing_regions(frame, local_ty)?; + self.layout_of(local_ty).into() + })?; // Layouts of locals are requested a lot, so we cache them. state.layout.set(Some(layout)); diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs index 18cff2c5e0f..a26c2eca107 100644 --- a/compiler/rustc_const_eval/src/interpret/step.rs +++ b/compiler/rustc_const_eval/src/interpret/step.rs @@ -9,6 +9,7 @@ use rustc_middle::ty::layout::FnAbiOf; use rustc_middle::ty::{self, Instance, Ty}; use rustc_middle::{bug, mir, span_bug}; use rustc_span::source_map::Spanned; +use rustc_span::{DesugaringKind, Span}; use rustc_target::callconv::FnAbi; use tracing::{info, instrument, trace}; @@ -80,7 +81,9 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { use rustc_middle::mir::StatementKind::*; match &stmt.kind { - Assign(box (place, rvalue)) => self.eval_rvalue_into_place(rvalue, *place)?, + Assign(box (place, rvalue)) => { + self.eval_rvalue_into_place(rvalue, *place, stmt.source_info.span)? + } SetDiscriminant { place, variant_index } => { let dest = self.eval_place(**place)?; @@ -143,6 +146,9 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { // Defined to do nothing. These are added by optimization passes, to avoid changing the // size of MIR constantly. Nop => {} + + // Only used for temporary lifetime lints + BackwardIncompatibleDropHint { .. } => {} } interp_ok(()) @@ -156,6 +162,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { &mut self, rvalue: &mir::Rvalue<'tcx>, place: mir::Place<'tcx>, + span: Span, ) -> InterpResult<'tcx> { let dest = self.eval_place(place)?; // FIXME: ensure some kind of non-aliasing between LHS and RHS? @@ -247,8 +254,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { let src = self.eval_place(place)?; let place = self.force_allocation(&src)?; let mut val = ImmTy::from_immediate(place.to_ref(self), dest.layout); - if !place_base_raw { + if !place_base_raw + && span.desugaring_kind() != Some(DesugaringKind::IndexBoundsCheckReborrow) + { // If this was not already raw, it needs retagging. + // As a special hack, we exclude the desugared `PtrMetadata(&raw const *_n)` + // from indexing. (Really we should not do any retag on `&raw` but that does not + // currently work with Stacked Borrows.) val = M::retag_ptr_value(self, mir::RetagKind::Raw, &val)?; } self.write_immediate(*val, &dest)?; @@ -418,7 +430,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> { .collect::<InterpResult<'tcx, Vec<_>>>()?; let fn_sig_binder = func.layout.ty.fn_sig(*self.tcx); - let fn_sig = self.tcx.normalize_erasing_late_bound_regions(self.param_env, fn_sig_binder); + let fn_sig = self.tcx.normalize_erasing_late_bound_regions(self.typing_env, fn_sig_binder); let extra_args = &args[fn_sig.inputs().len()..]; let extra_args = self.tcx.mk_type_list_from_iter(extra_args.iter().map(|arg| arg.layout().ty)); diff --git a/compiler/rustc_const_eval/src/interpret/util.rs b/compiler/rustc_const_eval/src/interpret/util.rs index 8bb5f173a56..ecb7c3fc93c 100644 --- a/compiler/rustc_const_eval/src/interpret/util.rs +++ b/compiler/rustc_const_eval/src/interpret/util.rs @@ -14,10 +14,8 @@ use crate::const_eval::{CompileTimeInterpCx, CompileTimeMachine, InterpretationR /// Checks whether a type contains generic parameters which must be instantiated. /// -/// In case it does, returns a `TooGeneric` const eval error. Note that due to polymorphization -/// types may be "concrete enough" even though they still contain generic parameters in -/// case these parameters are unused. -pub(crate) fn ensure_monomorphic_enough<'tcx, T>(tcx: TyCtxt<'tcx>, ty: T) -> InterpResult<'tcx> +/// In case it does, returns a `TooGeneric` const eval error. +pub(crate) fn ensure_monomorphic_enough<'tcx, T>(_tcx: TyCtxt<'tcx>, ty: T) -> InterpResult<'tcx> where T: TypeVisitable<TyCtxt<'tcx>>, { @@ -27,11 +25,9 @@ where } struct FoundParam; - struct UsedParamsNeedInstantiationVisitor<'tcx> { - tcx: TyCtxt<'tcx>, - } + struct UsedParamsNeedInstantiationVisitor {} - impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for UsedParamsNeedInstantiationVisitor<'tcx> { + impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for UsedParamsNeedInstantiationVisitor { type Result = ControlFlow<FoundParam>; fn visit_ty(&mut self, ty: Ty<'tcx>) -> Self::Result { @@ -41,25 +37,7 @@ where match *ty.kind() { ty::Param(_) => ControlFlow::Break(FoundParam), - ty::Closure(def_id, args) - | ty::CoroutineClosure(def_id, args, ..) - | ty::Coroutine(def_id, args, ..) - | ty::FnDef(def_id, args) => { - let instance = ty::InstanceKind::Item(def_id); - let unused_params = self.tcx.unused_generic_params(instance); - for (index, arg) in args.into_iter().enumerate() { - let index = index - .try_into() - .expect("more generic parameters than can fit into a `u32`"); - // Only recurse when generic parameters in fns, closures and coroutines - // are used and have to be instantiated. - // - // Just in case there are closures or coroutines within this arg, - // recurse. - if unused_params.is_used(index) && arg.has_param() { - return arg.visit_with(self); - } - } + ty::Closure(..) | ty::CoroutineClosure(..) | ty::Coroutine(..) | ty::FnDef(..) => { ControlFlow::Continue(()) } _ => ty.super_visit_with(self), @@ -74,7 +52,7 @@ where } } - let mut vis = UsedParamsNeedInstantiationVisitor { tcx }; + let mut vis = UsedParamsNeedInstantiationVisitor {}; if matches!(ty.visit_with(&mut vis), ControlFlow::Break(FoundParam)) { throw_inval!(TooGeneric); } else { diff --git a/compiler/rustc_const_eval/src/interpret/validity.rs b/compiler/rustc_const_eval/src/interpret/validity.rs index cd2c1ef3613..6f101395ccf 100644 --- a/compiler/rustc_const_eval/src/interpret/validity.rs +++ b/compiler/rustc_const_eval/src/interpret/validity.rs @@ -26,13 +26,13 @@ use rustc_middle::mir::interpret::{ }; use rustc_middle::ty::layout::{LayoutCx, LayoutOf, TyAndLayout}; use rustc_middle::ty::{self, Ty}; -use rustc_span::symbol::{Symbol, sym}; +use rustc_span::{Symbol, sym}; use tracing::trace; use super::machine::AllocMap; use super::{ - AllocId, AllocKind, CheckInAllocMsg, GlobalAlloc, ImmTy, Immediate, InterpCx, InterpResult, - MPlaceTy, Machine, MemPlaceMeta, PlaceTy, Pointer, Projectable, Scalar, ValueVisitor, err_ub, + AllocId, CheckInAllocMsg, GlobalAlloc, ImmTy, Immediate, InterpCx, InterpResult, MPlaceTy, + Machine, MemPlaceMeta, PlaceTy, Pointer, Projectable, Scalar, ValueVisitor, err_ub, format_interp_error, }; @@ -302,7 +302,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { }; } } - Variants::Single { .. } => {} + Variants::Single { .. } | Variants::Empty => {} } // Now we know we are projecting to a field, so figure out which one. @@ -344,6 +344,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { // Inside a variant PathElem::Field(def.variant(index).fields[FieldIdx::from_usize(field)].name) } + Variants::Empty => panic!("there is no field in Variants::Empty types"), Variants::Multiple { .. } => bug!("we handled variants above"), } } @@ -448,7 +449,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { meta: MemPlaceMeta<M::Provenance>, pointee: TyAndLayout<'tcx>, ) -> InterpResult<'tcx> { - let tail = self.ecx.tcx.struct_tail_for_codegen(pointee.ty, self.ecx.param_env); + let tail = self.ecx.tcx.struct_tail_for_codegen(pointee.ty, self.ecx.typing_env); match tail.kind() { ty::Dynamic(data, _, ty::Dyn) => { let vtable = meta.unwrap_meta().to_pointer(self.ecx)?; @@ -557,9 +558,20 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { if let Ok((alloc_id, _offset, _prov)) = self.ecx.ptr_try_get_alloc_id(place.ptr(), 0) { - if let Some(GlobalAlloc::Static(did)) = - self.ecx.tcx.try_get_global_alloc(alloc_id) - { + // Everything should be already interned. + let Some(global_alloc) = self.ecx.tcx.try_get_global_alloc(alloc_id) else { + assert!(self.ecx.memory.alloc_map.get(alloc_id).is_none()); + // We can't have *any* references to non-existing allocations in const-eval + // as the rest of rustc isn't happy with them... so we throw an error, even + // though for zero-sized references this isn't really UB. + // A potential future alternative would be to resurrect this as a zero-sized allocation + // (which codegen will then compile to an aligned dummy pointer anyway). + throw_validation_failure!(self.path, DanglingPtrUseAfterFree { ptr_kind }); + }; + let (size, _align) = + global_alloc.size_and_align(*self.ecx.tcx, self.ecx.typing_env); + + if let GlobalAlloc::Static(did) = global_alloc { let DefKind::Static { nested, .. } = self.ecx.tcx.def_kind(did) else { bug!() }; @@ -593,17 +605,6 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } } - // Dangling and Mutability check. - let (size, _align, alloc_kind) = self.ecx.get_alloc_info(alloc_id); - if alloc_kind == AllocKind::Dead { - // This can happen for zero-sized references. We can't have *any* references to - // non-existing allocations in const-eval though, interning rejects them all as - // the rest of rustc isn't happy with them... so we throw an error, even though - // this isn't really UB. - // A potential future alternative would be to resurrect this as a zero-sized allocation - // (which codegen will then compile to an aligned dummy pointer anyway). - throw_validation_failure!(self.path, DanglingPtrUseAfterFree { ptr_kind }); - } // If this allocation has size zero, there is no actual mutability here. if size != Size::ZERO { // Determine whether this pointer expects to be pointing to something mutable. @@ -618,7 +619,8 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } }; // Determine what it actually points to. - let alloc_actual_mutbl = mutability(self.ecx, alloc_id); + let alloc_actual_mutbl = + global_alloc.mutability(*self.ecx.tcx, self.ecx.typing_env); // Mutable pointer to immutable memory is no good. if ptr_expected_mutbl == Mutability::Mut && alloc_actual_mutbl == Mutability::Not @@ -842,9 +844,16 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } fn in_mutable_memory(&self, val: &PlaceTy<'tcx, M::Provenance>) -> bool { + debug_assert!(self.ctfe_mode.is_some()); if let Some(mplace) = val.as_mplace_or_local().left() { if let Some(alloc_id) = mplace.ptr().provenance.and_then(|p| p.get_alloc_id()) { - mutability(self.ecx, alloc_id).is_mut() + let tcx = *self.ecx.tcx; + // Everything must be already interned. + let mutbl = tcx.global_alloc(alloc_id).mutability(tcx, self.ecx.typing_env); + if let Some((_, alloc)) = self.ecx.memory.alloc_map.get(alloc_id) { + assert_eq!(alloc.mutability, mutbl); + } + mutbl.is_mut() } else { // No memory at all. false @@ -947,7 +956,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { ) -> Cow<'e, RangeSet> { assert!(layout.ty.is_union()); assert!(layout.is_sized(), "there are no unsized unions"); - let layout_cx = LayoutCx::new(*ecx.tcx, ecx.param_env); + let layout_cx = LayoutCx::new(*ecx.tcx, ecx.typing_env); return M::cached_union_data_range(ecx, layout.ty, || { let mut out = RangeSet(Vec::new()); union_data_range_uncached(&layout_cx, layout, Size::ZERO, &mut out); @@ -1002,7 +1011,7 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } // Don't forget potential other variants. match &layout.variants { - Variants::Single { .. } => { + Variants::Single { .. } | Variants::Empty => { // Fully handled above. } Variants::Multiple { variants, .. } => { @@ -1016,53 +1025,6 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValidityVisitor<'rt, 'tcx, M> { } } -/// Returns whether the allocation is mutable, and whether it's actually a static. -/// For "root" statics we look at the type to account for interior -/// mutability; for nested statics we have no type and directly use the annotated mutability. -fn mutability<'tcx>(ecx: &InterpCx<'tcx, impl Machine<'tcx>>, alloc_id: AllocId) -> Mutability { - // Let's see what kind of memory this points to. - // We're not using `try_global_alloc` since dangling pointers have already been handled. - match ecx.tcx.global_alloc(alloc_id) { - GlobalAlloc::Static(did) => { - let DefKind::Static { safety: _, mutability, nested } = ecx.tcx.def_kind(did) else { - bug!() - }; - if nested { - assert!( - ecx.memory.alloc_map.get(alloc_id).is_none(), - "allocations of nested statics are already interned: {alloc_id:?}, {did:?}" - ); - // Nested statics in a `static` are never interior mutable, - // so just use the declared mutability. - mutability - } else { - let mutability = match mutability { - Mutability::Not - if !ecx - .tcx - .type_of(did) - .no_bound_vars() - .expect("statics should not have generic parameters") - .is_freeze(*ecx.tcx, ty::ParamEnv::reveal_all()) => - { - Mutability::Mut - } - _ => mutability, - }; - if let Some((_, alloc)) = ecx.memory.alloc_map.get(alloc_id) { - assert_eq!(alloc.mutability, mutability); - } - mutability - } - } - GlobalAlloc::Memory(alloc) => alloc.inner().mutability, - GlobalAlloc::Function { .. } | GlobalAlloc::VTable(..) => { - // These are immutable, we better don't allow mutable pointers here. - Mutability::Not - } - } -} - impl<'rt, 'tcx, M: Machine<'tcx>> ValueVisitor<'tcx, M> for ValidityVisitor<'rt, 'tcx, M> { type V = PlaceTy<'tcx, M::Provenance>; @@ -1124,7 +1086,8 @@ impl<'rt, 'tcx, M: Machine<'tcx>> ValueVisitor<'tcx, M> for ValidityVisitor<'rt, ) -> InterpResult<'tcx> { // Special check for CTFE validation, preventing `UnsafeCell` inside unions in immutable memory. if self.ctfe_mode.is_some_and(|c| !c.allow_immutable_unsafe_cell()) { - if !val.layout.is_zst() && !val.layout.ty.is_freeze(*self.ecx.tcx, self.ecx.param_env) { + if !val.layout.is_zst() && !val.layout.ty.is_freeze(*self.ecx.tcx, self.ecx.typing_env) + { if !self.in_mutable_memory(val) { throw_validation_failure!(self.path, UnsafeCellInImmutable); } diff --git a/compiler/rustc_const_eval/src/interpret/visitor.rs b/compiler/rustc_const_eval/src/interpret/visitor.rs index 76ab0bb544f..3647c109a6e 100644 --- a/compiler/rustc_const_eval/src/interpret/visitor.rs +++ b/compiler/rustc_const_eval/src/interpret/visitor.rs @@ -218,8 +218,8 @@ pub trait ValueVisitor<'tcx, M: Machine<'tcx>>: Sized { // recurse with the inner type self.visit_variant(v, idx, &inner)?; } - // For single-variant layouts, we already did anything there is to do. - Variants::Single { .. } => {} + // For single-variant layouts, we already did everything there is to do. + Variants::Single { .. } | Variants::Empty => {} } interp_ok(()) diff --git a/compiler/rustc_const_eval/src/lib.rs b/compiler/rustc_const_eval/src/lib.rs index 0490195caf4..b5adf06b300 100644 --- a/compiler/rustc_const_eval/src/lib.rs +++ b/compiler/rustc_const_eval/src/lib.rs @@ -10,6 +10,7 @@ #![feature(never_type)] #![feature(rustdoc_internals)] #![feature(slice_ptr_get)] +#![feature(strict_overflow_ops)] #![feature(trait_alias)] #![feature(try_blocks)] #![feature(unqualified_local_imports)] @@ -40,14 +41,13 @@ pub fn provide(providers: &mut Providers) { providers.eval_to_allocation_raw = const_eval::eval_to_allocation_raw_provider; providers.eval_static_initializer = const_eval::eval_static_initializer_provider; providers.hooks.const_caller_location = util::caller_location::const_caller_location_provider; - providers.eval_to_valtree = |tcx, param_env_and_value| { - let (param_env, raw) = param_env_and_value.into_parts(); - const_eval::eval_to_valtree(tcx, param_env, raw) + providers.eval_to_valtree = |tcx, ty::PseudoCanonicalInput { typing_env, value }| { + const_eval::eval_to_valtree(tcx, typing_env, value) }; providers.hooks.try_destructure_mir_constant_for_user_output = const_eval::try_destructure_mir_constant_for_user_output; providers.valtree_to_const_val = |tcx, (ty, valtree)| { - const_eval::valtree_to_const_value(tcx, ty::ParamEnv::empty().and(ty), valtree) + const_eval::valtree_to_const_value(tcx, ty::TypingEnv::fully_monomorphized(), ty, valtree) }; providers.check_validity_requirement = |tcx, (init_kind, param_env_and_ty)| { util::check_validity_requirement(tcx, init_kind, param_env_and_ty) diff --git a/compiler/rustc_const_eval/src/util/alignment.rs b/compiler/rustc_const_eval/src/util/alignment.rs index 6fa7d369229..9507b24f603 100644 --- a/compiler/rustc_const_eval/src/util/alignment.rs +++ b/compiler/rustc_const_eval/src/util/alignment.rs @@ -9,7 +9,7 @@ use tracing::debug; pub fn is_disaligned<'tcx, L>( tcx: TyCtxt<'tcx>, local_decls: &L, - param_env: ty::ParamEnv<'tcx>, + typing_env: ty::TypingEnv<'tcx>, place: Place<'tcx>, ) -> bool where @@ -22,8 +22,8 @@ where }; let ty = place.ty(local_decls, tcx).ty; - let unsized_tail = || tcx.struct_tail_for_codegen(ty, param_env); - match tcx.layout_of(param_env.and(ty)) { + let unsized_tail = || tcx.struct_tail_for_codegen(ty, typing_env); + match tcx.layout_of(typing_env.as_query_input(ty)) { Ok(layout) if layout.align.abi <= pack && (layout.is_sized() diff --git a/compiler/rustc_const_eval/src/util/caller_location.rs b/compiler/rustc_const_eval/src/util/caller_location.rs index 7f4c36835e4..6dd9447cf5a 100644 --- a/compiler/rustc_const_eval/src/util/caller_location.rs +++ b/compiler/rustc_const_eval/src/util/caller_location.rs @@ -1,9 +1,9 @@ use rustc_hir::LangItem; use rustc_middle::query::TyCtxtAt; use rustc_middle::ty::layout::LayoutOf; -use rustc_middle::ty::{self, Mutability}; +use rustc_middle::ty::{self}; use rustc_middle::{bug, mir}; -use rustc_span::symbol::Symbol; +use rustc_span::Symbol; use tracing::trace; use crate::const_eval::{CanAccessMutGlobal, CompileTimeInterpCx, mk_eval_cx_to_read_const_val}; @@ -20,12 +20,9 @@ fn alloc_caller_location<'tcx>( // This can fail if rustc runs out of memory right here. Trying to emit an error would be // pointless, since that would require allocating more memory than these short strings. let file = if loc_details.file { - ecx.allocate_str(filename.as_str(), MemoryKind::CallerLocation, Mutability::Not).unwrap() + ecx.allocate_str_dedup(filename.as_str()).unwrap() } else { - // FIXME: This creates a new allocation each time. It might be preferable to - // perform this allocation only once, and re-use the `MPlaceTy`. - // See https://github.com/rust-lang/rust/pull/89920#discussion_r730012398 - ecx.allocate_str("<redacted>", MemoryKind::CallerLocation, Mutability::Not).unwrap() + ecx.allocate_str_dedup("<redacted>").unwrap() }; let file = file.map_provenance(CtfeProvenance::as_immutable); let line = if loc_details.line { Scalar::from_u32(line) } else { Scalar::from_u32(0) }; @@ -60,7 +57,7 @@ pub(crate) fn const_caller_location_provider( let mut ecx = mk_eval_cx_to_read_const_val( tcx.tcx, tcx.span, - ty::ParamEnv::reveal_all(), + ty::TypingEnv::fully_monomorphized(), CanAccessMutGlobal::No, ); diff --git a/compiler/rustc_const_eval/src/util/check_validity_requirement.rs b/compiler/rustc_const_eval/src/util/check_validity_requirement.rs index f743525f359..a729d9325c8 100644 --- a/compiler/rustc_const_eval/src/util/check_validity_requirement.rs +++ b/compiler/rustc_const_eval/src/util/check_validity_requirement.rs @@ -3,7 +3,7 @@ use rustc_middle::bug; use rustc_middle::ty::layout::{ HasTyCtxt, LayoutCx, LayoutError, LayoutOf, TyAndLayout, ValidityRequirement, }; -use rustc_middle::ty::{ParamEnvAnd, Ty, TyCtxt}; +use rustc_middle::ty::{PseudoCanonicalInput, Ty, TyCtxt}; use crate::const_eval::{CanAccessMutGlobal, CheckAlignment, CompileTimeMachine}; use crate::interpret::{InterpCx, MemoryKind}; @@ -23,16 +23,16 @@ use crate::interpret::{InterpCx, MemoryKind}; pub fn check_validity_requirement<'tcx>( tcx: TyCtxt<'tcx>, kind: ValidityRequirement, - param_env_and_ty: ParamEnvAnd<'tcx, Ty<'tcx>>, + input: PseudoCanonicalInput<'tcx, Ty<'tcx>>, ) -> Result<bool, &'tcx LayoutError<'tcx>> { - let layout = tcx.layout_of(param_env_and_ty)?; + let layout = tcx.layout_of(input)?; // There is nothing strict or lax about inhabitedness. if kind == ValidityRequirement::Inhabited { return Ok(!layout.is_uninhabited()); } - let layout_cx = LayoutCx::new(tcx, param_env_and_ty.param_env); + let layout_cx = LayoutCx::new(tcx, input.typing_env); if kind == ValidityRequirement::Uninit || tcx.sess.opts.unstable_opts.strict_init_checks { check_validity_requirement_strict(layout, &layout_cx, kind) } else { @@ -49,7 +49,7 @@ fn check_validity_requirement_strict<'tcx>( ) -> Result<bool, &'tcx LayoutError<'tcx>> { let machine = CompileTimeMachine::new(CanAccessMutGlobal::No, CheckAlignment::Error); - let mut cx = InterpCx::new(cx.tcx(), rustc_span::DUMMY_SP, cx.param_env, machine); + let mut cx = InterpCx::new(cx.tcx(), rustc_span::DUMMY_SP, cx.typing_env, machine); let allocated = cx .allocate(ty, MemoryKind::Machine(crate::const_eval::MemoryKind::Heap)) @@ -155,6 +155,7 @@ fn check_validity_requirement_lax<'tcx>( } match &this.variants { + Variants::Empty => return Ok(false), Variants::Single { .. } => { // All fields of this single variant have already been checked above, there is nothing // else to do. diff --git a/compiler/rustc_const_eval/src/util/compare_types.rs b/compiler/rustc_const_eval/src/util/compare_types.rs index 0cf27d30c36..9eed1a20f15 100644 --- a/compiler/rustc_const_eval/src/util/compare_types.rs +++ b/compiler/rustc_const_eval/src/util/compare_types.rs @@ -5,18 +5,17 @@ use rustc_infer::infer::TyCtxtInferExt; use rustc_middle::traits::ObligationCause; -use rustc_middle::ty::{ParamEnv, Ty, TyCtxt, TypingMode, Variance}; +use rustc_middle::ty::{Ty, TyCtxt, TypingEnv, Variance}; use rustc_trait_selection::traits::ObligationCtxt; /// Returns whether `src` is a subtype of `dest`, i.e. `src <: dest`. pub fn sub_types<'tcx>( tcx: TyCtxt<'tcx>, - typing_mode: TypingMode<'tcx>, - param_env: ParamEnv<'tcx>, + typing_env: TypingEnv<'tcx>, src: Ty<'tcx>, dest: Ty<'tcx>, ) -> bool { - relate_types(tcx, typing_mode, param_env, Variance::Covariant, src, dest) + relate_types(tcx, typing_env, Variance::Covariant, src, dest) } /// Returns whether `src` is a subtype of `dest`, i.e. `src <: dest`. @@ -26,8 +25,7 @@ pub fn sub_types<'tcx>( /// because we want to check for type equality. pub fn relate_types<'tcx>( tcx: TyCtxt<'tcx>, - typing_mode: TypingMode<'tcx>, - param_env: ParamEnv<'tcx>, + typing_env: TypingEnv<'tcx>, variance: Variance, src: Ty<'tcx>, dest: Ty<'tcx>, @@ -36,8 +34,7 @@ pub fn relate_types<'tcx>( return true; } - let mut builder = tcx.infer_ctxt().ignoring_regions(); - let infcx = builder.build(typing_mode); + let (infcx, param_env) = tcx.infer_ctxt().ignoring_regions().build_with_typing_env(typing_env); let ocx = ObligationCtxt::new(&infcx); let cause = ObligationCause::dummy(); let src = ocx.normalize(&cause, param_env, src); |