Skip to content

Commit b4ea2b2

Browse files
matthiaskrgrmatthiaskrgr
authored
Rollup merge of rust-lang#135195 - oli-obk:push-toyoyrupruko, r=lcnr
Make `lit_to_mir_constant` and `lit_to_const` infallible My motivation for this change is just that it's annoying to check everywhere, especially since all but one call site was just ICEing on errors anyway right there. They can still fail, but now just return an error constant instead of having the caller handle the error. fixes rust-lang#114317 fixes rust-lang#126182
2 parents 614e17b + c92ed62 commit b4ea2b2

File tree

15 files changed

+143
-175
lines changed

15 files changed

+143
-175
lines changed

‎compiler/rustc_hir_analysis/src/hir_ty_lowering/mod.rs‎

Lines changed: 7 additions & 27 deletions
Original file line numberDiff line numberDiff line change
@@ -35,7 +35,7 @@ use rustc_hir::{self as hir, AnonConst, GenericArg, GenericArgs, HirId};
3535
use rustc_infer::infer::{InferCtxt, TyCtxtInferExt};
3636
use rustc_infer::traits::ObligationCause;
3737
use rustc_middle::middle::stability::AllowUnstable;
38-
use rustc_middle::mir::interpret::{LitToConstError, LitToConstInput};
38+
use rustc_middle::mir::interpret::LitToConstInput;
3939
use rustc_middle::ty::fold::fold_regions;
4040
use rustc_middle::ty::print::PrintPolyTraitRefExt as _;
4141
use rustc_middle::ty::{
@@ -2262,25 +2262,11 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
22622262
_ => None,
22632263
};
22642264

2265-
if let Some(lit_input) = lit_input {
2266-
// If an error occurred, ignore that it's a literal and leave reporting the error up to
2267-
// mir.
2268-
match tcx.at(expr.span).lit_to_const(lit_input) {
2269-
Ok(c) => return Some(c),
2270-
Err(_) if lit_input.ty.has_aliases() => {
2271-
// allow the `ty` to be an alias type, though we cannot handle it here
2272-
return None;
2273-
}
2274-
Err(e) => {
2275-
tcx.dcx().span_delayed_bug(
2276-
expr.span,
2277-
format!("try_lower_anon_const_lit: couldn't lit_to_const {e:?}"),
2278-
);
2279-
}
2280-
}
2281-
}
2282-
2283-
None
2265+
lit_input
2266+
// Allow the `ty` to be an alias type, though we cannot handle it here, we just go through
2267+
// the more expensive anon const code path.
2268+
.filter(|l| !l.ty.has_aliases())
2269+
.map(|l| tcx.at(expr.span).lit_to_const(l))
22842270
}
22852271

22862272
fn lower_delegation_ty(&self, idx: hir::InferDelegationKind) -> Ty<'tcx> {
@@ -2460,13 +2446,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
24602446
hir::ExprKind::Lit(lit) => {
24612447
let lit_input =
24622448
LitToConstInput { lit: &lit.node, ty, neg: neg.is_some() };
2463-
let ct = match tcx.lit_to_const(lit_input) {
2464-
Ok(c) => c,
2465-
Err(LitToConstError::Reported(err)) => {
2466-
ty::Const::new_error(tcx, err)
2467-
}
2468-
Err(LitToConstError::TypeError) => todo!(),
2469-
};
2449+
let ct = tcx.lit_to_const(lit_input);
24702450
(ct, ty)
24712451
}
24722452

‎compiler/rustc_middle/src/mir/interpret/mod.rs‎

Lines changed: 0 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -16,7 +16,6 @@ use rustc_abi::{AddressSpace, Align, Endian, HasDataLayout, Size};
1616
use rustc_ast::{LitKind, Mutability};
1717
use rustc_data_structures::fx::FxHashMap;
1818
use rustc_data_structures::sync::Lock;
19-
use rustc_errors::ErrorGuaranteed;
2019
use rustc_hir::def::DefKind;
2120
use rustc_hir::def_id::{DefId, LocalDefId};
2221
use rustc_macros::{HashStable, TyDecodable, TyEncodable, TypeFoldable, TypeVisitable};
@@ -84,16 +83,6 @@ pub struct LitToConstInput<'tcx> {
8483
pub neg: bool,
8584
}
8685

87-
/// Error type for `tcx.lit_to_const`.
88-
#[derive(Copy, Clone, Debug, Eq, PartialEq, HashStable)]
89-
pub enum LitToConstError {
90-
/// The literal's inferred type did not match the expected `ty` in the input.
91-
/// This is used for graceful error handling (`span_delayed_bug`) in
92-
/// type checking (`Const::from_anon_const`).
93-
TypeError,
94-
Reported(ErrorGuaranteed),
95-
}
96-
9786
#[derive(Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
9887
pub struct AllocId(pub NonZero<u64>);
9988

‎compiler/rustc_middle/src/query/erase.rs‎

Lines changed: 0 additions & 9 deletions
Original file line numberDiff line numberDiff line change
@@ -141,14 +141,6 @@ impl EraseType for Result<rustc_abi::TyAndLayout<'_, Ty<'_>>, &ty::layout::Layou
141141
>()];
142142
}
143143

144-
impl EraseType for Result<ty::Const<'_>, mir::interpret::LitToConstError> {
145-
type Result = [u8; size_of::<Result<ty::Const<'static>, mir::interpret::LitToConstError>>()];
146-
}
147-
148-
impl EraseType for Result<mir::Const<'_>, mir::interpret::LitToConstError> {
149-
type Result = [u8; size_of::<Result<mir::Const<'static>, mir::interpret::LitToConstError>>()];
150-
}
151-
152144
impl EraseType for Result<mir::ConstAlloc<'_>, mir::interpret::ErrorHandled> {
153145
type Result = [u8; size_of::<Result<mir::ConstAlloc<'static>, mir::interpret::ErrorHandled>>()];
154146
}
@@ -296,7 +288,6 @@ trivial! {
296288
rustc_middle::mir::interpret::AllocId,
297289
rustc_middle::mir::interpret::CtfeProvenance,
298290
rustc_middle::mir::interpret::ErrorHandled,
299-
rustc_middle::mir::interpret::LitToConstError,
300291
rustc_middle::thir::ExprId,
301292
rustc_middle::traits::CodegenObligationError,
302293
rustc_middle::traits::EvaluationResult,

‎compiler/rustc_middle/src/query/mod.rs‎

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -57,7 +57,7 @@ use crate::middle::resolve_bound_vars::{ObjectLifetimeDefault, ResolveBoundVars,
5757
use crate::middle::stability::{self, DeprecationEntry};
5858
use crate::mir::interpret::{
5959
EvalStaticInitializerRawResult, EvalToAllocationRawResult, EvalToConstValueResult,
60-
EvalToValTreeResult, GlobalId, LitToConstError, LitToConstInput,
60+
EvalToValTreeResult, GlobalId, LitToConstInput,
6161
};
6262
use crate::mir::mono::{CodegenUnit, CollectionMode, MonoItem};
6363
use crate::query::erase::{Erase, erase, restore};
@@ -1268,7 +1268,7 @@ rustc_queries! {
12681268
// FIXME get rid of this with valtrees
12691269
query lit_to_const(
12701270
key: LitToConstInput<'tcx>
1271-
) -> Result<ty::Const<'tcx>, LitToConstError> {
1271+
) -> ty::Const<'tcx> {
12721272
desc { "converting literal to const" }
12731273
}
12741274

‎compiler/rustc_mir_build/src/builder/expr/as_constant.rs‎

Lines changed: 21 additions & 31 deletions
Original file line numberDiff line numberDiff line change
@@ -3,13 +3,12 @@
33
use rustc_abi::Size;
44
use rustc_ast as ast;
55
use rustc_hir::LangItem;
6-
use rustc_middle::mir::interpret::{
7-
Allocation, CTFE_ALLOC_SALT, LitToConstError, LitToConstInput, Scalar,
8-
};
6+
use rustc_middle::mir::interpret::{Allocation, CTFE_ALLOC_SALT, LitToConstInput, Scalar};
97
use rustc_middle::mir::*;
108
use rustc_middle::thir::*;
119
use rustc_middle::ty::{
12-
self, CanonicalUserType, CanonicalUserTypeAnnotation, Ty, TyCtxt, UserTypeAnnotationIndex,
10+
self, CanonicalUserType, CanonicalUserTypeAnnotation, Ty, TyCtxt, TypeVisitableExt as _,
11+
UserTypeAnnotationIndex,
1312
};
1413
use rustc_middle::{bug, mir, span_bug};
1514
use tracing::{instrument, trace};
@@ -50,16 +49,7 @@ pub(crate) fn as_constant_inner<'tcx>(
5049
let Expr { ty, temp_lifetime: _, span, ref kind } = *expr;
5150
match *kind {
5251
ExprKind::Literal { lit, neg } => {
53-
let const_ = match lit_to_mir_constant(tcx, LitToConstInput { lit: &lit.node, ty, neg })
54-
{
55-
Ok(c) => c,
56-
Err(LitToConstError::Reported(guar)) => {
57-
Const::Ty(Ty::new_error(tcx, guar), ty::Const::new_error(tcx, guar))
58-
}
59-
Err(LitToConstError::TypeError) => {
60-
bug!("encountered type error in `lit_to_mir_constant`")
61-
}
62-
};
52+
let const_ = lit_to_mir_constant(tcx, LitToConstInput { lit: &lit.node, ty, neg });
6353

6454
ConstOperand { span, user_ty: None, const_ }
6555
}
@@ -108,11 +98,13 @@ pub(crate) fn as_constant_inner<'tcx>(
10898
}
10999

110100
#[instrument(skip(tcx, lit_input))]
111-
fn lit_to_mir_constant<'tcx>(
112-
tcx: TyCtxt<'tcx>,
113-
lit_input: LitToConstInput<'tcx>,
114-
) -> Result<Const<'tcx>, LitToConstError> {
101+
fn lit_to_mir_constant<'tcx>(tcx: TyCtxt<'tcx>, lit_input: LitToConstInput<'tcx>) -> Const<'tcx> {
115102
let LitToConstInput { lit, ty, neg } = lit_input;
103+
104+
if let Err(guar) = ty.error_reported() {
105+
return Const::Ty(Ty::new_error(tcx, guar), ty::Const::new_error(tcx, guar));
106+
}
107+
116108
let trunc = |n| {
117109
let width = match tcx.layout_of(ty::TypingEnv::fully_monomorphized().as_query_input(ty)) {
118110
Ok(layout) => layout.size,
@@ -123,7 +115,7 @@ fn lit_to_mir_constant<'tcx>(
123115
trace!("trunc {} with size {} and shift {}", n, width.bits(), 128 - width.bits());
124116
let result = width.truncate(n);
125117
trace!("trunc result: {}", result);
126-
Ok(ConstValue::Scalar(Scalar::from_uint(result, width)))
118+
ConstValue::Scalar(Scalar::from_uint(result, width))
127119
};
128120

129121
let value = match (lit, ty.kind()) {
@@ -154,20 +146,18 @@ fn lit_to_mir_constant<'tcx>(
154146
ConstValue::Scalar(Scalar::from_uint(*n, Size::from_bytes(1)))
155147
}
156148
(ast::LitKind::Int(n, _), ty::Uint(_)) | (ast::LitKind::Int(n, _), ty::Int(_)) => {
157-
trunc(if neg { (n.get() as i128).overflowing_neg().0 as u128 } else { n.get() })?
158-
}
159-
(ast::LitKind::Float(n, _), ty::Float(fty)) => parse_float_into_constval(*n, *fty, neg)
160-
.ok_or_else(|| {
161-
LitToConstError::Reported(
162-
tcx.dcx()
163-
.delayed_bug(format!("couldn't parse float literal: {:?}", lit_input.lit)),
164-
)
165-
})?,
149+
trunc(if neg { (n.get() as i128).overflowing_neg().0 as u128 } else { n.get() })
150+
}
151+
(ast::LitKind::Float(n, _), ty::Float(fty)) => {
152+
parse_float_into_constval(*n, *fty, neg).unwrap()
153+
}
166154
(ast::LitKind::Bool(b), ty::Bool) => ConstValue::Scalar(Scalar::from_bool(*b)),
167155
(ast::LitKind::Char(c), ty::Char) => ConstValue::Scalar(Scalar::from_char(*c)),
168-
(ast::LitKind::Err(guar), _) => return Err(LitToConstError::Reported(*guar)),
169-
_ => return Err(LitToConstError::TypeError),
156+
(ast::LitKind::Err(guar), _) => {
157+
return Const::Ty(Ty::new_error(tcx, *guar), ty::Const::new_error(tcx, *guar));
158+
}
159+
_ => bug!("invalid lit/ty combination in `lit_to_mir_constant`: {lit:?}: {ty:?}"),
170160
};
171161

172-
Ok(Const::Val(value, ty))
162+
Const::Val(value, ty)
173163
}

‎compiler/rustc_mir_build/src/thir/constant.rs‎

Lines changed: 11 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -1,7 +1,7 @@
11
use rustc_ast as ast;
22
use rustc_hir::LangItem;
33
use rustc_middle::bug;
4-
use rustc_middle::mir::interpret::{LitToConstError, LitToConstInput};
4+
use rustc_middle::mir::interpret::LitToConstInput;
55
use rustc_middle::ty::{self, ScalarInt, TyCtxt, TypeVisitableExt as _};
66
use tracing::trace;
77

@@ -10,11 +10,11 @@ use crate::builder::parse_float_into_scalar;
1010
pub(crate) fn lit_to_const<'tcx>(
1111
tcx: TyCtxt<'tcx>,
1212
lit_input: LitToConstInput<'tcx>,
13-
) -> Result<ty::Const<'tcx>, LitToConstError> {
13+
) -> ty::Const<'tcx> {
1414
let LitToConstInput { lit, ty, neg } = lit_input;
1515

1616
if let Err(guar) = ty.error_reported() {
17-
return Ok(ty::Const::new_error(tcx, guar));
17+
return ty::Const::new_error(tcx, guar);
1818
}
1919

2020
let trunc = |n| {
@@ -28,8 +28,8 @@ pub(crate) fn lit_to_const<'tcx>(
2828
let result = width.truncate(n);
2929
trace!("trunc result: {}", result);
3030

31-
Ok(ScalarInt::try_from_uint(result, width)
32-
.unwrap_or_else(|| bug!("expected to create ScalarInt from uint {:?}", result)))
31+
ScalarInt::try_from_uint(result, width)
32+
.unwrap_or_else(|| bug!("expected to create ScalarInt from uint {:?}", result))
3333
};
3434

3535
let valtree = match (lit, ty.kind()) {
@@ -57,20 +57,20 @@ pub(crate) fn lit_to_const<'tcx>(
5757
}
5858
(ast::LitKind::Int(n, _), ty::Uint(_)) | (ast::LitKind::Int(n, _), ty::Int(_)) => {
5959
let scalar_int =
60-
trunc(if neg { (n.get() as i128).overflowing_neg().0 as u128 } else { n.get() })?;
60+
trunc(if neg { (n.get() as i128).overflowing_neg().0 as u128 } else { n.get() });
6161
ty::ValTree::from_scalar_int(scalar_int)
6262
}
6363
(ast::LitKind::Bool(b), ty::Bool) => ty::ValTree::from_scalar_int((*b).into()),
6464
(ast::LitKind::Float(n, _), ty::Float(fty)) => {
65-
let bits = parse_float_into_scalar(*n, *fty, neg).ok_or_else(|| {
65+
let bits = parse_float_into_scalar(*n, *fty, neg).unwrap_or_else(|| {
6666
tcx.dcx().bug(format!("couldn't parse float literal: {:?}", lit_input.lit))
67-
})?;
67+
});
6868
ty::ValTree::from_scalar_int(bits)
6969
}
7070
(ast::LitKind::Char(c), ty::Char) => ty::ValTree::from_scalar_int((*c).into()),
71-
(ast::LitKind::Err(guar), _) => return Err(LitToConstError::Reported(*guar)),
72-
_ => return Err(LitToConstError::TypeError),
71+
(ast::LitKind::Err(guar), _) => return ty::Const::new_error(tcx, *guar),
72+
_ => return ty::Const::new_misc_error(tcx),
7373
};
7474

75-
Ok(ty::Const::new_value(tcx, valtree, ty))
75+
ty::Const::new_value(tcx, valtree, ty)
7676
}

‎compiler/rustc_mir_build/src/thir/pattern/mod.rs‎

Lines changed: 3 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -13,7 +13,7 @@ use rustc_hir::pat_util::EnumerateAndAdjustIterator;
1313
use rustc_hir::{self as hir, ByRef, Mutability, RangeEnd};
1414
use rustc_index::Idx;
1515
use rustc_lint as lint;
16-
use rustc_middle::mir::interpret::{LitToConstError, LitToConstInput};
16+
use rustc_middle::mir::interpret::LitToConstInput;
1717
use rustc_middle::thir::{
1818
Ascription, FieldPat, LocalVarId, Pat, PatKind, PatRange, PatRangeBoundary,
1919
};
@@ -682,11 +682,8 @@ impl<'a, 'tcx> PatCtxt<'a, 'tcx> {
682682

683683
let ct_ty = self.typeck_results.expr_ty(expr);
684684
let lit_input = LitToConstInput { lit: &lit.node, ty: ct_ty, neg };
685-
match self.tcx.at(expr.span).lit_to_const(lit_input) {
686-
Ok(constant) => self.const_to_pat(constant, ct_ty, expr.hir_id, lit.span).kind,
687-
Err(LitToConstError::Reported(e)) => PatKind::Error(e),
688-
Err(LitToConstError::TypeError) => bug!("lower_lit: had type error"),
689-
}
685+
let constant = self.tcx.at(expr.span).lit_to_const(lit_input);
686+
self.const_to_pat(constant, ct_ty, expr.hir_id, lit.span).kind
690687
}
691688
}
692689

‎compiler/rustc_ty_utils/src/consts.rs‎

Lines changed: 2 additions & 8 deletions
Original file line numberDiff line numberDiff line change
@@ -4,7 +4,7 @@ use rustc_abi::{FIRST_VARIANT, VariantIdx};
44
use rustc_errors::ErrorGuaranteed;
55
use rustc_hir::def::DefKind;
66
use rustc_hir::def_id::LocalDefId;
7-
use rustc_middle::mir::interpret::{LitToConstError, LitToConstInput};
7+
use rustc_middle::mir::interpret::LitToConstInput;
88
use rustc_middle::query::Providers;
99
use rustc_middle::thir::visit;
1010
use rustc_middle::thir::visit::Visitor;
@@ -118,13 +118,7 @@ fn recurse_build<'tcx>(
118118
}
119119
&ExprKind::Literal { lit, neg } => {
120120
let sp = node.span;
121-
match tcx.at(sp).lit_to_const(LitToConstInput { lit: &lit.node, ty: node.ty, neg }) {
122-
Ok(c) => c,
123-
Err(LitToConstError::Reported(guar)) => ty::Const::new_error(tcx, guar),
124-
Err(LitToConstError::TypeError) => {
125-
bug!("encountered type error in lit_to_const")
126-
}
127-
}
121+
tcx.at(sp).lit_to_const(LitToConstInput { lit: &lit.node, ty: node.ty, neg })
128122
}
129123
&ExprKind::NonHirLiteral { lit, user_ty: _ } => {
130124
let val = ty::ValTree::from_scalar_int(lit);

‎tests/crashes/114317.rs‎

Lines changed: 0 additions & 6 deletions
This file was deleted.

‎tests/crashes/126182.rs‎

Lines changed: 0 additions & 10 deletions
This file was deleted.

0 commit comments

Comments
 (0)