diff options
| -rw-r--r-- | src/librustc/mir/interpret/error.rs | 7 | ||||
| -rw-r--r-- | src/librustc_mir/interpret/operand.rs | 8 | ||||
| -rw-r--r-- | src/librustc_mir/interpret/place.rs | 16 | ||||
| -rw-r--r-- | src/librustc_mir/interpret/validity.rs | 2 | ||||
| -rw-r--r-- | src/test/ui/consts/const-eval/write-to-uninhabited-enum-variant.rs | 28 |
5 files changed, 48 insertions, 13 deletions
diff --git a/src/librustc/mir/interpret/error.rs b/src/librustc/mir/interpret/error.rs index ac99ccd45ea..d918b9ee673 100644 --- a/src/librustc/mir/interpret/error.rs +++ b/src/librustc/mir/interpret/error.rs @@ -363,6 +363,8 @@ pub enum UndefinedBehaviorInfo { UbExperimental(String), /// Unreachable code was executed. Unreachable, + /// An enum discriminant was set to a value which was outside the range of valid values. + InvalidDiscriminant(ScalarMaybeUndef), } impl fmt::Debug for UndefinedBehaviorInfo { @@ -373,6 +375,8 @@ impl fmt::Debug for UndefinedBehaviorInfo { write!(f, "{}", msg), Unreachable => write!(f, "entered unreachable code"), + InvalidDiscriminant(val) => + write!(f, "encountered invalid enum discriminant {}", val), } } } @@ -400,7 +404,6 @@ pub enum UnsupportedOpInfo<'tcx> { InvalidMemoryAccess, InvalidFunctionPointer, InvalidBool, - InvalidDiscriminant(ScalarMaybeUndef), PointerOutOfBounds { ptr: Pointer, msg: CheckInAllocMsg, @@ -485,8 +488,6 @@ impl fmt::Debug for UnsupportedOpInfo<'tcx> { write!(f, "incorrect alloc info: expected size {} and align {}, \ got size {} and align {}", size.bytes(), align.bytes(), size2.bytes(), align2.bytes()), - InvalidDiscriminant(val) => - write!(f, "encountered invalid enum discriminant {}", val), InvalidMemoryAccess => write!(f, "tried to access memory through an invalid pointer"), DanglingPointerDeref => diff --git a/src/librustc_mir/interpret/operand.rs b/src/librustc_mir/interpret/operand.rs index 4bdd71f9602..4d9be55945e 100644 --- a/src/librustc_mir/interpret/operand.rs +++ b/src/librustc_mir/interpret/operand.rs @@ -647,7 +647,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { let bits_discr = raw_discr .not_undef() .and_then(|raw_discr| self.force_bits(raw_discr, discr_val.layout.size)) - .map_err(|_| err_unsup!(InvalidDiscriminant(raw_discr.erase_tag())))?; + .map_err(|_| err_ub!(InvalidDiscriminant(raw_discr.erase_tag())))?; let real_discr = if discr_val.layout.ty.is_signed() { // going from layout tag type to typeck discriminant type // requires first sign extending with the discriminant layout @@ -677,7 +677,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { _ => bug!("tagged layout for non-adt non-generator"), }.ok_or_else( - || err_unsup!(InvalidDiscriminant(raw_discr.erase_tag())) + || err_ub!(InvalidDiscriminant(raw_discr.erase_tag())) )?; (real_discr, index.0) }, @@ -689,7 +689,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { let variants_start = niche_variants.start().as_u32(); let variants_end = niche_variants.end().as_u32(); let raw_discr = raw_discr.not_undef().map_err(|_| { - err_unsup!(InvalidDiscriminant(ScalarMaybeUndef::Undef)) + err_ub!(InvalidDiscriminant(ScalarMaybeUndef::Undef)) })?; match raw_discr.to_bits_or_ptr(discr_val.layout.size, self) { Err(ptr) => { @@ -697,7 +697,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { let ptr_valid = niche_start == 0 && variants_start == variants_end && !self.memory.ptr_may_be_null(ptr); if !ptr_valid { - throw_unsup!(InvalidDiscriminant(raw_discr.erase_tag().into())) + throw_ub!(InvalidDiscriminant(raw_discr.erase_tag().into())) } (dataful_variant.as_u32() as u128, dataful_variant) }, diff --git a/src/librustc_mir/interpret/place.rs b/src/librustc_mir/interpret/place.rs index 903eb3c1c44..0289c52fd37 100644 --- a/src/librustc_mir/interpret/place.rs +++ b/src/librustc_mir/interpret/place.rs @@ -1031,9 +1031,13 @@ where variant_index: VariantIdx, dest: PlaceTy<'tcx, M::PointerTag>, ) -> InterpResult<'tcx> { + let variant_scalar = Scalar::from_u32(variant_index.as_u32()).into(); + match dest.layout.variants { layout::Variants::Single { index } => { - assert_eq!(index, variant_index); + if index != variant_index { + throw_ub!(InvalidDiscriminant(variant_scalar)); + } } layout::Variants::Multiple { discr_kind: layout::DiscriminantKind::Tag, @@ -1041,7 +1045,9 @@ where discr_index, .. } => { - assert!(dest.layout.ty.variant_range(*self.tcx).unwrap().contains(&variant_index)); + if !dest.layout.ty.variant_range(*self.tcx).unwrap().contains(&variant_index) { + throw_ub!(InvalidDiscriminant(variant_scalar)); + } let discr_val = dest.layout.ty.discriminant_for_variant(*self.tcx, variant_index).unwrap().val; @@ -1064,9 +1070,9 @@ where discr_index, .. } => { - assert!( - variant_index.as_usize() < dest.layout.ty.ty_adt_def().unwrap().variants.len(), - ); + if !variant_index.as_usize() < dest.layout.ty.ty_adt_def().unwrap().variants.len() { + throw_ub!(InvalidDiscriminant(variant_scalar)); + } if variant_index != dataful_variant { let variants_start = niche_variants.start().as_u32(); let variant_index_relative = variant_index.as_u32() diff --git a/src/librustc_mir/interpret/validity.rs b/src/librustc_mir/interpret/validity.rs index 853fcb1beab..3444fb60f33 100644 --- a/src/librustc_mir/interpret/validity.rs +++ b/src/librustc_mir/interpret/validity.rs @@ -344,7 +344,7 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M> match self.walk_value(op) { Ok(()) => Ok(()), Err(err) => match err.kind { - err_unsup!(InvalidDiscriminant(val)) => + err_ub!(InvalidDiscriminant(val)) => throw_validation_failure!( val, self.path, "a valid enum discriminant" ), diff --git a/src/test/ui/consts/const-eval/write-to-uninhabited-enum-variant.rs b/src/test/ui/consts/const-eval/write-to-uninhabited-enum-variant.rs new file mode 100644 index 00000000000..cccb7879fc0 --- /dev/null +++ b/src/test/ui/consts/const-eval/write-to-uninhabited-enum-variant.rs @@ -0,0 +1,28 @@ +// run-pass + +#![allow(dead_code)] + +enum Empty { } +enum Test1 { + A(u8), + B(Empty), +} +enum Test2 { + A(u8), + B(Empty), + C, +} + +fn bar() -> Option<Empty> { + None +} + +fn main() { + if let Some(x) = bar() { + Test1::B(x); + } + + if let Some(x) = bar() { + Test2::B(x); + } +} |