pub enum UndefinedBehaviorInfo {
Show 28 variants Ub(String), Unreachable, BoundsCheckFailed { len: u64, index: u64, }, DivisionByZero, RemainderByZero, DivisionOverflow, RemainderOverflow, PointerArithOverflow, InvalidMeta(&'static str), UnterminatedCString(Pointer<AllocId>), PointerUseAfterFree(AllocId), PointerOutOfBounds { alloc_id: AllocId, alloc_size: Size, ptr_offset: i64, ptr_size: Size, msg: CheckInAllocMsg, }, DanglingIntPointer(u64CheckInAllocMsg), AlignmentCheckFailed { required: Align, has: Align, }, WriteToReadOnly(AllocId), DerefFunctionPointer(AllocId), DerefVTablePointer(AllocId), ValidationFailure { path: Option<String>, msg: String, }, InvalidBool(u8), InvalidChar(u32), InvalidTag(Scalar<AllocId>), InvalidFunctionPointer(Pointer<AllocId>), InvalidVTablePointer(Pointer<AllocId>), InvalidStr(Utf8Error), InvalidUninitBytes(Option<(AllocId, UninitBytesAccess)>), DeadLocal, ScalarSizeMismatch(ScalarSizeMismatch), UninhabitedEnumVariantWritten,
}
Expand description

Error information for when the program caused Undefined Behavior.

Variants

Ub(String)

Free-form case. Only for errors that are never caught!

Unreachable

Unreachable code was executed.

BoundsCheckFailed

Fields

len: u64
index: u64

A slice/array index projection went out-of-bounds.

DivisionByZero

Something was divided by 0 (x / 0).

RemainderByZero

Something was “remainded” by 0 (x % 0).

DivisionOverflow

Signed division overflowed (INT_MIN / -1).

RemainderOverflow

Signed remainder overflowed (INT_MIN % -1).

PointerArithOverflow

Overflowing inbounds pointer arithmetic.

InvalidMeta(&'static str)

Invalid metadata in a wide pointer (using str to avoid allocations).

UnterminatedCString(Pointer<AllocId>)

Reading a C string that does not end within its allocation.

PointerUseAfterFree(AllocId)

Dereferencing a dangling pointer after it got freed.

PointerOutOfBounds

Fields

alloc_id: AllocId
alloc_size: Size
ptr_offset: i64
ptr_size: Size

Used a pointer outside the bounds it is valid for. (If ptr_size > 0, determines the size of the memory range that was expected to be in-bounds.)

DanglingIntPointer(u64CheckInAllocMsg)

Using an integer as a pointer in the wrong way.

AlignmentCheckFailed

Fields

required: Align
has: Align

Used a pointer with bad alignment.

WriteToReadOnly(AllocId)

Writing to read-only memory.

DerefFunctionPointer(AllocId)

DerefVTablePointer(AllocId)

ValidationFailure

Fields

path: Option<String>

The “path” to the value in question, e.g. .0[5].field for a struct field in the 6th element of an array that is the first element of a tuple.

msg: String

The value validity check found a problem. Should only be thrown by validity.rs and always point out which part of the value is the problem.

InvalidBool(u8)

Using a non-boolean u8 as bool.

InvalidChar(u32)

Using a non-character u32 as character.

InvalidTag(Scalar<AllocId>)

The tag of an enum does not encode an actual discriminant.

InvalidFunctionPointer(Pointer<AllocId>)

Using a pointer-not-to-a-function as function pointer.

InvalidVTablePointer(Pointer<AllocId>)

Using a pointer-not-to-a-vtable as vtable pointer.

InvalidStr(Utf8Error)

Using a string that is not valid UTF-8,

InvalidUninitBytes(Option<(AllocId, UninitBytesAccess)>)

Using uninitialized data where it is not allowed.

DeadLocal

Working with a local that is not currently live.

ScalarSizeMismatch(ScalarSizeMismatch)

Data size is not equal to target size.

UninhabitedEnumVariantWritten

A discriminant of an uninhabited enum variant is written.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Converts the given value to a String. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference’s “Type Layout” chapter for details on type layout guarantees.

Size: 56 bytes

Size for each variant:

  • Ub: 31 bytes
  • Unreachable: 0 bytes
  • BoundsCheckFailed: 23 bytes
  • DivisionByZero: 0 bytes
  • RemainderByZero: 0 bytes
  • DivisionOverflow: 0 bytes
  • RemainderOverflow: 0 bytes
  • PointerArithOverflow: 0 bytes
  • InvalidMeta: 23 bytes
  • UnterminatedCString: 23 bytes
  • PointerUseAfterFree: 15 bytes
  • PointerOutOfBounds: 39 bytes
  • DanglingIntPointer: 15 bytes
  • AlignmentCheckFailed: 2 bytes
  • WriteToReadOnly: 15 bytes
  • DerefFunctionPointer: 15 bytes
  • DerefVTablePointer: 15 bytes
  • ValidationFailure: 55 bytes
  • InvalidBool: 1 byte
  • InvalidChar: 7 bytes
  • InvalidTag: 31 bytes
  • InvalidFunctionPointer: 23 bytes
  • InvalidVTablePointer: 23 bytes
  • InvalidStr: 23 bytes
  • InvalidUninitBytes: 47 bytes
  • DeadLocal: 0 bytes
  • ScalarSizeMismatch: 23 bytes
  • UninhabitedEnumVariantWritten: 0 bytes