use rustc_hir as hir;
use rustc_hir::def_id::DefId;
use rustc_middle::mir::{
- Body, CastKind, NullOp, Operand, Place, ProjectionElem, Rvalue, Statement, StatementKind, Terminator,
- TerminatorKind,
+ Body, CastKind, NonDivergingIntrinsic, NullOp, Operand, Place, ProjectionElem, Rvalue, Statement, StatementKind,
+ Terminator, TerminatorKind,
};
use rustc_middle::ty::subst::GenericArgKind;
use rustc_middle::ty::{self, adjustment::PointerCast, Ty, TyCtxt};
use rustc_semver::RustcVersion;
use rustc_span::symbol::sym;
use rustc_span::Span;
-use rustc_target::spec::abi::Abi::RustIntrinsic;
use std::borrow::Cow;
type McfResult = Result<(), (Span, Cow<'static, str>)>;
| ty::PredicateKind::ConstEquate(..)
| ty::PredicateKind::Trait(..)
| ty::PredicateKind::TypeWellFormedFromEnv(..) => continue,
- ty::PredicateKind::ObjectSafe(_) => panic!("object safe predicate on function: {:#?}", predicate),
- ty::PredicateKind::ClosureKind(..) => panic!("closure kind predicate on function: {:#?}", predicate),
- ty::PredicateKind::Subtype(_) => panic!("subtype predicate on function: {:#?}", predicate),
- ty::PredicateKind::Coerce(_) => panic!("coerce predicate on function: {:#?}", predicate),
+ ty::PredicateKind::ObjectSafe(_) => panic!("object safe predicate on function: {predicate:#?}"),
+ ty::PredicateKind::ClosureKind(..) => panic!("closure kind predicate on function: {predicate:#?}"),
+ ty::PredicateKind::Subtype(_) => panic!("subtype predicate on function: {predicate:#?}"),
+ ty::PredicateKind::Coerce(_) => panic!("coerce predicate on function: {predicate:#?}"),
}
}
match predicates.parent {
body.local_decls.iter().next().unwrap().source_info.span,
)?;
- for bb in body.basic_blocks() {
+ for bb in body.basic_blocks.iter() {
check_terminator(tcx, body, bb.terminator(), msrv)?;
for stmt in &bb.statements {
check_statement(tcx, body, def_id, stmt)?;
ty::FnPtr(..) => {
return Err((span, "function pointers in const fn are unstable".into()));
},
- ty::Dynamic(preds, _) => {
+ ty::Dynamic(preds, _, _) => {
for pred in preds.iter() {
match pred.skip_binder() {
ty::ExistentialPredicate::AutoTrait(_) | ty::ExistentialPredicate::Projection(_) => {
) -> McfResult {
match rvalue {
Rvalue::ThreadLocalRef(_) => Err((span, "cannot access thread local storage in const fn".into())),
- Rvalue::Repeat(operand, _) | Rvalue::Use(operand) => check_operand(tcx, operand, span, body),
Rvalue::Len(place) | Rvalue::Discriminant(place) | Rvalue::Ref(_, _, place) | Rvalue::AddressOf(_, place) => {
check_place(tcx, *place, span, body)
},
- Rvalue::Cast(CastKind::Misc, operand, cast_ty) => {
- use rustc_middle::ty::cast::CastTy;
- let cast_in = CastTy::from_ty(operand.ty(body, tcx)).expect("bad input type for cast");
- let cast_out = CastTy::from_ty(*cast_ty).expect("bad output type for cast");
- match (cast_in, cast_out) {
- (CastTy::Ptr(_) | CastTy::FnPtr, CastTy::Int(_)) => {
- Err((span, "casting pointers to ints is unstable in const fn".into()))
- },
- _ => check_operand(tcx, operand, span, body),
- }
- },
- Rvalue::Cast(CastKind::Pointer(PointerCast::MutToConstPointer | PointerCast::ArrayToPointer), operand, _) => {
- check_operand(tcx, operand, span, body)
- },
+ Rvalue::CopyForDeref(place) => check_place(tcx, *place, span, body),
+ Rvalue::Repeat(operand, _)
+ | Rvalue::Use(operand)
+ | Rvalue::Cast(
+ CastKind::PointerFromExposedAddress
+ | CastKind::Misc
+ | CastKind::Pointer(PointerCast::MutToConstPointer | PointerCast::ArrayToPointer),
+ operand,
+ _,
+ ) => check_operand(tcx, operand, span, body),
Rvalue::Cast(
CastKind::Pointer(
PointerCast::UnsafeFnPointer | PointerCast::ClosureFnPointer(_) | PointerCast::ReifyFnPointer,
Err((span, "unsizing casts are not allowed in const fn".into()))
}
},
+ Rvalue::Cast(CastKind::PointerExposeAddress, _, _) => {
+ Err((span, "casting pointers to ints is unstable in const fn".into()))
+ },
+ Rvalue::Cast(CastKind::DynStar, _, _) => {
+ // FIXME(dyn-star)
+ unimplemented!()
+ },
// binops are fine on integers
Rvalue::BinaryOp(_, box (lhs, rhs)) | Rvalue::CheckedBinaryOp(_, box (lhs, rhs)) => {
check_operand(tcx, lhs, span, body)?;
check_place(tcx, **place, span, body)
},
- StatementKind::CopyNonOverlapping(box rustc_middle::mir::CopyNonOverlapping { dst, src, count }) => {
+ StatementKind::Intrinsic(box NonDivergingIntrinsic::Assume(op)) => check_operand(tcx, op, span, body),
+
+ StatementKind::Intrinsic(box NonDivergingIntrinsic::CopyNonOverlapping(
+ rustc_middle::mir::CopyNonOverlapping { dst, src, count },
+ )) => {
check_operand(tcx, dst, span, body)?;
check_operand(tcx, src, span, body)?;
check_operand(tcx, count, span, body)
}
},
ProjectionElem::ConstantIndex { .. }
+ | ProjectionElem::OpaqueCast(..)
| ProjectionElem::Downcast(..)
| ProjectionElem::Subslice { .. }
| ProjectionElem::Deref
args,
from_hir_call: _,
destination: _,
+ target: _,
cleanup: _,
fn_span: _,
} => {
span,
format!(
"can only call other `const fn` within a `const fn`, \
- but `{:?}` is not stable as `const fn`",
- func,
+ but `{func:?}` is not stable as `const fn`",
)
.into(),
));
// within const fns. `transmute` is allowed in all other const contexts.
// This won't really scale to more intrinsics or functions. Let's allow const
// transmutes in const fn before we add more hacks to this.
- if tcx.fn_sig(fn_def_id).abi() == RustIntrinsic && tcx.item_name(fn_def_id) == sym::transmute {
+ if tcx.is_intrinsic(fn_def_id) && tcx.item_name(fn_def_id) == sym::transmute {
return Err((
span,
"can only call `transmute` from const items, not `const fn`".into(),
fn is_const_fn(tcx: TyCtxt<'_>, def_id: DefId, msrv: Option<RustcVersion>) -> bool {
tcx.is_const_fn(def_id)
&& tcx.lookup_const_stability(def_id).map_or(true, |const_stab| {
- if let rustc_attr::StabilityLevel::Stable { since } = const_stab.level {
+ if let rustc_attr::StabilityLevel::Stable { since, .. } = const_stab.level {
// Checking MSRV is manually necessary because `rustc` has no such concept. This entire
// function could be removed if `rustc` provided a MSRV-aware version of `is_const_fn`.
// as a part of an unimplemented MSRV check https://github.com/rust-lang/rust/issues/65262.
+
+ // HACK(nilstrieb): CURRENT_RUSTC_VERSION can return versions like 1.66.0-dev. `rustc-semver`
+ // doesn't accept the `-dev` version number so we have to strip it
+ // off.
+ let short_version = since
+ .as_str()
+ .split('-')
+ .next()
+ .expect("rustc_attr::StabilityLevel::Stable::since` is empty");
+
+ let since = rustc_span::Symbol::intern(short_version);
+
crate::meets_msrv(
msrv,
- RustcVersion::parse(since.as_str())
- .expect("`rustc_attr::StabilityLevel::Stable::since` is ill-formatted"),
+ RustcVersion::parse(since.as_str()).unwrap_or_else(|err| {
+ panic!("`rustc_attr::StabilityLevel::Stable::since` is ill-formatted: `{since}`, {err:?}")
+ }),
)
} else {
// Unstable const fn with the feature enabled.