4 use crate::hir::map::definitions::DefPathData;
6 use crate::ty::{self, Ty, layout};
7 use crate::ty::layout::{Size, Align, LayoutError};
8 use rustc_target::spec::abi::Abi;
9 use rustc_macros::HashStable;
11 use super::{RawConst, Pointer, CheckInAllocMsg, ScalarMaybeUndef};
13 use backtrace::Backtrace;
15 use crate::ty::query::TyCtxtAt;
16 use errors::DiagnosticBuilder;
18 use syntax_pos::{Pos, Span};
19 use syntax::symbol::Symbol;
21 #[derive(Debug, Copy, Clone, PartialEq, Eq, HashStable, RustcEncodable, RustcDecodable)]
22 pub enum ErrorHandled {
23 /// Already reported a lint or an error for this evaluation.
25 /// Don't emit an error, the evaluation failed because the MIR was generic
26 /// and the substs didn't fully monomorphize it.
31 pub fn assert_reported(self) {
33 ErrorHandled::Reported => {},
34 ErrorHandled::TooGeneric => bug!("MIR interpretation failed without reporting an error \
35 even though it was fully monomorphized"),
40 CloneTypeFoldableImpls! {
44 pub type ConstEvalRawResult<'tcx> = Result<RawConst<'tcx>, ErrorHandled>;
45 pub type ConstEvalResult<'tcx> = Result<&'tcx ty::Const<'tcx>, ErrorHandled>;
47 #[derive(Clone, Debug, RustcEncodable, RustcDecodable)]
48 pub struct ConstEvalErr<'tcx> {
50 pub error: crate::mir::interpret::InterpError<'tcx>,
51 pub stacktrace: Vec<FrameInfo<'tcx>>,
54 #[derive(Clone, Debug, RustcEncodable, RustcDecodable, HashStable)]
55 pub struct FrameInfo<'tcx> {
56 /// This span is in the caller.
58 pub instance: ty::Instance<'tcx>,
59 pub lint_root: Option<hir::HirId>,
62 impl<'tcx> fmt::Display for FrameInfo<'tcx> {
63 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
65 if tcx.def_key(self.instance.def_id()).disambiguated_data.data
66 == DefPathData::ClosureExpr
68 write!(f, "inside call to closure")?;
70 write!(f, "inside call to `{}`", self.instance)?;
72 if !self.call_site.is_dummy() {
73 let lo = tcx.sess.source_map().lookup_char_pos(self.call_site.lo());
74 write!(f, " at {}:{}:{}", lo.file.name, lo.line, lo.col.to_usize() + 1)?;
81 impl<'tcx> ConstEvalErr<'tcx> {
86 ) -> Result<DiagnosticBuilder<'tcx>, ErrorHandled> {
87 self.struct_generic(tcx, message, None)
90 pub fn report_as_error(&self, tcx: TyCtxtAt<'tcx>, message: &str) -> ErrorHandled {
91 let err = self.struct_error(tcx, message);
95 ErrorHandled::Reported
101 pub fn report_as_lint(
105 lint_root: hir::HirId,
108 let lint = self.struct_generic(
115 if let Some(span) = span {
116 let primary_spans = lint.span.primary_spans().to_vec();
117 // point at the actual error as the primary span
118 lint.replace_span_with(span);
119 // point to the `const` statement as a secondary span
120 // they don't have any label
121 for sp in primary_spans {
123 lint.span_label(sp, "");
128 ErrorHandled::Reported
138 lint_root: Option<hir::HirId>,
139 ) -> Result<DiagnosticBuilder<'tcx>, ErrorHandled> {
141 InterpError::Layout(LayoutError::Unknown(_)) |
142 InterpError::TooGeneric => return Err(ErrorHandled::TooGeneric),
143 InterpError::Layout(LayoutError::SizeOverflow(_)) |
144 InterpError::TypeckError => return Err(ErrorHandled::Reported),
147 trace!("reporting const eval failure at {:?}", self.span);
148 let mut err = if let Some(lint_root) = lint_root {
149 let hir_id = self.stacktrace
152 .filter_map(|frame| frame.lint_root)
154 .unwrap_or(lint_root);
155 tcx.struct_span_lint_hir(
156 crate::rustc::lint::builtin::CONST_ERR,
162 struct_error(tcx, message)
164 err.span_label(self.span, self.error.to_string());
165 // Skip the last, which is just the environment of the constant. The stacktrace
166 // is sometimes empty because we create "fake" eval contexts in CTFE to do work
167 // on constant values.
168 if self.stacktrace.len() > 0 {
169 for frame_info in &self.stacktrace[..self.stacktrace.len()-1] {
170 err.span_label(frame_info.call_site, frame_info.to_string());
177 pub fn struct_error<'tcx>(tcx: TyCtxtAt<'tcx>, msg: &str) -> DiagnosticBuilder<'tcx> {
178 struct_span_err!(tcx.sess, tcx.span, E0080, "{}", msg)
181 /// Packages the kind of error we got from the const code interpreter
182 /// up with a Rust-level backtrace of where the error occured.
183 /// Thsese should always be constructed by calling `.into()` on
184 /// a `InterpError`. In `librustc_mir::interpret`, we have the `err!`
186 #[derive(Debug, Clone)]
187 pub struct InterpErrorInfo<'tcx> {
188 pub kind: InterpError<'tcx>,
189 backtrace: Option<Box<Backtrace>>,
193 impl fmt::Display for InterpErrorInfo<'_> {
194 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
195 write!(f, "{}", self.kind)
199 impl InterpErrorInfo<'_> {
200 pub fn print_backtrace(&mut self) {
201 if let Some(ref mut backtrace) = self.backtrace {
202 print_backtrace(&mut *backtrace);
207 fn print_backtrace(backtrace: &mut Backtrace) {
209 eprintln!("\n\nAn error occurred in miri:\n{:?}", backtrace);
212 impl<'tcx> From<InterpError<'tcx>> for InterpErrorInfo<'tcx> {
213 fn from(kind: InterpError<'tcx>) -> Self {
214 let backtrace = match env::var("RUST_CTFE_BACKTRACE") {
215 // Matching `RUST_BACKTRACE` -- we treat "0" the same as "not present".
216 Ok(ref val) if val != "0" => {
217 let mut backtrace = Backtrace::new_unresolved();
219 if val == "immediate" {
221 print_backtrace(&mut backtrace);
224 Some(Box::new(backtrace))
236 #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)]
237 pub enum PanicMessage<O> {
248 Overflow(mir::BinOp),
252 GeneratorResumedAfterReturn,
253 GeneratorResumedAfterPanic,
256 /// Type for MIR `Assert` terminator error messages.
257 pub type AssertMessage<'tcx> = PanicMessage<mir::Operand<'tcx>>;
259 impl<O> PanicMessage<O> {
260 /// Getting a description does not require `O` to be printable, and does not
261 /// require allocation.
262 /// The caller is expected to handle `Panic` and `BoundsCheck` separately.
263 pub fn description(&self) -> &'static str {
266 Overflow(mir::BinOp::Add) =>
267 "attempt to add with overflow",
268 Overflow(mir::BinOp::Sub) =>
269 "attempt to subtract with overflow",
270 Overflow(mir::BinOp::Mul) =>
271 "attempt to multiply with overflow",
272 Overflow(mir::BinOp::Div) =>
273 "attempt to divide with overflow",
274 Overflow(mir::BinOp::Rem) =>
275 "attempt to calculate the remainder with overflow",
277 "attempt to negate with overflow",
278 Overflow(mir::BinOp::Shr) =>
279 "attempt to shift right with overflow",
280 Overflow(mir::BinOp::Shl) =>
281 "attempt to shift left with overflow",
283 bug!("{:?} cannot overflow", op),
285 "attempt to divide by zero",
287 "attempt to calculate the remainder with a divisor of zero",
288 GeneratorResumedAfterReturn =>
289 "generator resumed after completion",
290 GeneratorResumedAfterPanic =>
291 "generator resumed after panicking",
292 Panic { .. } | BoundsCheck { .. } =>
293 bug!("Unexpected PanicMessage"),
298 impl<O: fmt::Debug> fmt::Debug for PanicMessage<O> {
299 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
302 Panic { ref msg, line, col, ref file } =>
303 write!(f, "the evaluated program panicked at '{}', {}:{}:{}", msg, file, line, col),
304 BoundsCheck { ref len, ref index } =>
305 write!(f, "index out of bounds: the len is {:?} but the index is {:?}", len, index),
307 write!(f, "{}", self.description()),
312 #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)]
313 pub enum InterpError<'tcx> {
314 /// This variant is used by machines to signal their own errors that do not
315 /// match an existing variant.
316 MachineError(String),
318 /// Not actually an interpreter error -- used to signal that execution has exited
319 /// with the given status code. Used by Miri, but not by CTFE.
322 FunctionAbiMismatch(Abi, Abi),
323 FunctionArgMismatch(Ty<'tcx>, Ty<'tcx>),
324 FunctionRetMismatch(Ty<'tcx>, Ty<'tcx>),
325 FunctionArgCountMismatch,
327 UnterminatedCString(Pointer),
328 DanglingPointerDeref,
331 InvalidFunctionPointer,
333 InvalidDiscriminant(ScalarMaybeUndef),
336 msg: CheckInAllocMsg,
337 allocation_size: Size,
339 InvalidNullPointerUsage,
344 ReadUndefBytes(Size),
346 InvalidBoolOp(mir::BinOp),
347 Unimplemented(String),
348 DerefFunctionPointer,
352 StackFrameLimitReached,
355 AbiViolation(String),
356 AlignmentCheckFailed {
360 ValidationFailure(String),
361 CalledClosureAsFunction,
362 VtableForArgumentlessMethod,
363 ModifiedConstantMemory,
367 TypeNotPrimitive(Ty<'tcx>),
368 ReallocatedWrongMemoryKind(String, String),
369 DeallocatedWrongMemoryKind(String, String),
370 ReallocateNonBasePtr,
371 DeallocateNonBasePtr,
372 IncorrectAllocationInformation(Size, Size, Align, Align),
373 Layout(layout::LayoutError<'tcx>),
375 HeapAllocNonPowerOfTwoAlignment(u64),
377 Panic(PanicMessage<u64>),
378 ReadFromReturnPointer,
379 PathNotFound(Vec<String>),
380 UnimplementedTraitSelection,
381 /// Abort in case type errors are reached
383 /// Resolution can fail if we are in a too generic context
385 /// Cannot compute this constant because it depends on another one
386 /// which already produced an error
391 pub type InterpResult<'tcx, T = ()> = Result<T, InterpErrorInfo<'tcx>>;
393 impl fmt::Display for InterpError<'_> {
394 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
395 // Forward `Display` to `Debug`
396 write!(f, "{:?}", self)
400 impl fmt::Debug for InterpError<'_> {
401 fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
404 PointerOutOfBounds { ptr, msg, allocation_size } => {
405 write!(f, "{} failed: pointer must be in-bounds at offset {}, \
406 but is outside bounds of allocation {} which has size {}",
407 msg, ptr.offset.bytes(), ptr.alloc_id, allocation_size.bytes())
409 ValidationFailure(ref err) => {
410 write!(f, "type validation failed: {}", err)
412 NoMirFor(ref func) => write!(f, "no mir for `{}`", func),
413 FunctionAbiMismatch(caller_abi, callee_abi) =>
414 write!(f, "tried to call a function with ABI {:?} using caller ABI {:?}",
415 callee_abi, caller_abi),
416 FunctionArgMismatch(caller_ty, callee_ty) =>
417 write!(f, "tried to call a function with argument of type {:?} \
418 passing data of type {:?}",
419 callee_ty, caller_ty),
420 FunctionRetMismatch(caller_ty, callee_ty) =>
421 write!(f, "tried to call a function with return type {:?} \
422 passing return place of type {:?}",
423 callee_ty, caller_ty),
424 FunctionArgCountMismatch =>
425 write!(f, "tried to call a function with incorrect number of arguments"),
426 ReallocatedWrongMemoryKind(ref old, ref new) =>
427 write!(f, "tried to reallocate memory from {} to {}", old, new),
428 DeallocatedWrongMemoryKind(ref old, ref new) =>
429 write!(f, "tried to deallocate {} memory but gave {} as the kind", old, new),
431 write!(f, "tried to interpret an invalid 32-bit value as a char: {}", c),
432 AlignmentCheckFailed { required, has } =>
433 write!(f, "tried to access memory with alignment {}, but alignment {} is required",
434 has.bytes(), required.bytes()),
435 TypeNotPrimitive(ty) =>
436 write!(f, "expected primitive type, got {}", ty),
438 write!(f, "rustc layout computation failed: {:?}", err),
439 PathNotFound(ref path) =>
440 write!(f, "Cannot find path {:?}", path),
441 IncorrectAllocationInformation(size, size2, align, align2) =>
442 write!(f, "incorrect alloc info: expected size {} and align {}, \
443 got size {} and align {}",
444 size.bytes(), align.bytes(), size2.bytes(), align2.bytes()),
445 InvalidDiscriminant(val) =>
446 write!(f, "encountered invalid enum discriminant {}", val),
448 write!(f, "exited with status code {}", code),
449 InvalidMemoryAccess =>
450 write!(f, "tried to access memory through an invalid pointer"),
451 DanglingPointerDeref =>
452 write!(f, "dangling pointer was dereferenced"),
454 write!(f, "tried to deallocate dangling pointer"),
455 InvalidFunctionPointer =>
456 write!(f, "tried to use a function pointer after offsetting it"),
458 write!(f, "invalid boolean value read"),
459 InvalidNullPointerUsage =>
460 write!(f, "invalid use of NULL pointer"),
461 ReadPointerAsBytes =>
462 write!(f, "a raw memory access tried to access part of a pointer value as raw \
464 ReadBytesAsPointer =>
465 write!(f, "a memory access tried to interpret some bytes as a pointer"),
467 write!(f, "tried to read from foreign (extern) static"),
468 InvalidPointerMath =>
469 write!(f, "attempted to do invalid arithmetic on pointers that would leak base \
470 addresses, e.g., comparing pointers into different allocations"),
472 write!(f, "tried to access a dead local variable"),
473 DerefFunctionPointer =>
474 write!(f, "tried to dereference a function pointer"),
476 write!(f, "tried to treat a memory pointer as a function pointer"),
477 StackFrameLimitReached =>
478 write!(f, "reached the configured maximum number of stack frames"),
480 write!(f, "reached the maximum number of representable TLS keys"),
482 write!(f, "accessed an invalid (unallocated) TLS key"),
483 CalledClosureAsFunction =>
484 write!(f, "tried to call a closure through a function pointer"),
485 VtableForArgumentlessMethod =>
486 write!(f, "tried to call a vtable function without arguments"),
487 ModifiedConstantMemory =>
488 write!(f, "tried to modify constant memory"),
490 write!(f, "tried to modify a static's initial value from another static's \
493 write!(f, "`assume` argument was false"),
495 write!(f, "miri does not support inline assembly"),
496 ReallocateNonBasePtr =>
497 write!(f, "tried to reallocate with a pointer not to the beginning of an \
499 DeallocateNonBasePtr =>
500 write!(f, "tried to deallocate with a pointer not to the beginning of an \
502 HeapAllocZeroBytes =>
503 write!(f, "tried to re-, de- or allocate zero bytes on the heap"),
505 write!(f, "entered unreachable code"),
506 ReadFromReturnPointer =>
507 write!(f, "tried to read from the return pointer"),
508 UnimplementedTraitSelection =>
509 write!(f, "there were unresolved type arguments during trait selection"),
511 write!(f, "encountered constants with type errors, stopping evaluation"),
513 write!(f, "encountered overly generic constant"),
514 ReferencedConstant =>
515 write!(f, "referenced constant has errors"),
517 write!(f, "duplicate interpreter state observed here, const evaluation will never \
520 write!(f, "invalid boolean operation"),
521 UnterminatedCString(_) =>
522 write!(f, "attempted to get length of a null terminated string, but no null \
523 found before end of allocation"),
525 write!(f, "attempted to read undefined bytes"),
526 HeapAllocNonPowerOfTwoAlignment(_) =>
527 write!(f, "tried to re-, de-, or allocate heap memory with alignment that is \
528 not a power of two"),
529 MachineError(ref msg) |
530 Unimplemented(ref msg) |
531 AbiViolation(ref msg) |
532 Intrinsic(ref msg) =>
533 write!(f, "{}", msg),
535 write!(f, "{:?}", msg),