| use super::{RawConst, Pointer, CheckInAllocMsg, ScalarMaybeUndef}; |
| |
| use crate::hir; |
| use crate::hir::map::definitions::DefPathData; |
| use crate::mir; |
| use crate::ty::{self, Ty, layout}; |
| use crate::ty::layout::{Size, Align, LayoutError}; |
| use crate::ty::query::TyCtxtAt; |
| |
| use backtrace::Backtrace; |
| use errors::DiagnosticBuilder; |
| use rustc_macros::HashStable; |
| use rustc_target::spec::abi::Abi; |
| use syntax_pos::{Pos, Span}; |
| use syntax::symbol::Symbol; |
| |
| use std::{fmt, env}; |
| |
| #[derive(Debug, Copy, Clone, PartialEq, Eq, HashStable, RustcEncodable, RustcDecodable)] |
| pub enum ErrorHandled { |
| /// Already reported a lint or an error for this evaluation. |
| Reported, |
| /// Don't emit an error, the evaluation failed because the MIR was generic |
| /// and the substs didn't fully monomorphize it. |
| TooGeneric, |
| } |
| |
| impl ErrorHandled { |
| pub fn assert_reported(self) { |
| match self { |
| ErrorHandled::Reported => {}, |
| ErrorHandled::TooGeneric => bug!("MIR interpretation failed without reporting an error \ |
| even though it was fully monomorphized"), |
| } |
| } |
| } |
| |
| CloneTypeFoldableImpls! { |
| ErrorHandled, |
| } |
| |
| pub type ConstEvalRawResult<'tcx> = Result<RawConst<'tcx>, ErrorHandled>; |
| pub type ConstEvalResult<'tcx> = Result<&'tcx ty::Const<'tcx>, ErrorHandled>; |
| |
| #[derive(Clone, Debug, RustcEncodable, RustcDecodable)] |
| pub struct ConstEvalErr<'tcx> { |
| pub span: Span, |
| pub error: crate::mir::interpret::InterpError<'tcx>, |
| pub stacktrace: Vec<FrameInfo<'tcx>>, |
| } |
| |
| #[derive(Clone, Debug, RustcEncodable, RustcDecodable, HashStable)] |
| pub struct FrameInfo<'tcx> { |
| /// This span is in the caller. |
| pub call_site: Span, |
| pub instance: ty::Instance<'tcx>, |
| pub lint_root: Option<hir::HirId>, |
| } |
| |
| impl<'tcx> fmt::Display for FrameInfo<'tcx> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| ty::tls::with(|tcx| { |
| if tcx.def_key(self.instance.def_id()).disambiguated_data.data |
| == DefPathData::ClosureExpr |
| { |
| write!(f, "inside call to closure")?; |
| } else { |
| write!(f, "inside call to `{}`", self.instance)?; |
| } |
| if !self.call_site.is_dummy() { |
| let lo = tcx.sess.source_map().lookup_char_pos(self.call_site.lo()); |
| write!(f, " at {}:{}:{}", lo.file.name, lo.line, lo.col.to_usize() + 1)?; |
| } |
| Ok(()) |
| }) |
| } |
| } |
| |
| impl<'tcx> ConstEvalErr<'tcx> { |
| pub fn struct_error( |
| &self, |
| tcx: TyCtxtAt<'tcx>, |
| message: &str, |
| ) -> Result<DiagnosticBuilder<'tcx>, ErrorHandled> { |
| self.struct_generic(tcx, message, None) |
| } |
| |
| pub fn report_as_error(&self, tcx: TyCtxtAt<'tcx>, message: &str) -> ErrorHandled { |
| let err = self.struct_error(tcx, message); |
| match err { |
| Ok(mut err) => { |
| err.emit(); |
| ErrorHandled::Reported |
| }, |
| Err(err) => err, |
| } |
| } |
| |
| pub fn report_as_lint( |
| &self, |
| tcx: TyCtxtAt<'tcx>, |
| message: &str, |
| lint_root: hir::HirId, |
| span: Option<Span>, |
| ) -> ErrorHandled { |
| let lint = self.struct_generic( |
| tcx, |
| message, |
| Some(lint_root), |
| ); |
| match lint { |
| Ok(mut lint) => { |
| if let Some(span) = span { |
| let primary_spans = lint.span.primary_spans().to_vec(); |
| // point at the actual error as the primary span |
| lint.replace_span_with(span); |
| // point to the `const` statement as a secondary span |
| // they don't have any label |
| for sp in primary_spans { |
| if sp != span { |
| lint.span_label(sp, ""); |
| } |
| } |
| } |
| lint.emit(); |
| ErrorHandled::Reported |
| }, |
| Err(err) => err, |
| } |
| } |
| |
| fn struct_generic( |
| &self, |
| tcx: TyCtxtAt<'tcx>, |
| message: &str, |
| lint_root: Option<hir::HirId>, |
| ) -> Result<DiagnosticBuilder<'tcx>, ErrorHandled> { |
| let must_error = match self.error { |
| err_inval!(Layout(LayoutError::Unknown(_))) | |
| err_inval!(TooGeneric) => |
| return Err(ErrorHandled::TooGeneric), |
| err_inval!(TypeckError) => |
| return Err(ErrorHandled::Reported), |
| err_inval!(Layout(LayoutError::SizeOverflow(_))) => true, |
| _ => false, |
| }; |
| trace!("reporting const eval failure at {:?}", self.span); |
| let mut err = if let (Some(lint_root), false) = (lint_root, must_error) { |
| let hir_id = self.stacktrace |
| .iter() |
| .rev() |
| .filter_map(|frame| frame.lint_root) |
| .next() |
| .unwrap_or(lint_root); |
| tcx.struct_span_lint_hir( |
| crate::rustc::lint::builtin::CONST_ERR, |
| hir_id, |
| tcx.span, |
| message, |
| ) |
| } else if must_error { |
| struct_error(tcx, &self.error.to_string()) |
| } else { |
| struct_error(tcx, message) |
| }; |
| if !must_error { |
| err.span_label(self.span, self.error.to_string()); |
| } |
| // Skip the last, which is just the environment of the constant. The stacktrace |
| // is sometimes empty because we create "fake" eval contexts in CTFE to do work |
| // on constant values. |
| if self.stacktrace.len() > 0 { |
| for frame_info in &self.stacktrace[..self.stacktrace.len()-1] { |
| err.span_label(frame_info.call_site, frame_info.to_string()); |
| } |
| } |
| Ok(err) |
| } |
| } |
| |
| pub fn struct_error<'tcx>(tcx: TyCtxtAt<'tcx>, msg: &str) -> DiagnosticBuilder<'tcx> { |
| struct_span_err!(tcx.sess, tcx.span, E0080, "{}", msg) |
| } |
| |
| /// Packages the kind of error we got from the const code interpreter |
| /// up with a Rust-level backtrace of where the error occured. |
| /// Thsese should always be constructed by calling `.into()` on |
| /// a `InterpError`. In `librustc_mir::interpret`, we have `throw_err_*` |
| /// macros for this. |
| #[derive(Debug, Clone)] |
| pub struct InterpErrorInfo<'tcx> { |
| pub kind: InterpError<'tcx>, |
| backtrace: Option<Box<Backtrace>>, |
| } |
| |
| |
| impl fmt::Display for InterpErrorInfo<'_> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| write!(f, "{}", self.kind) |
| } |
| } |
| |
| impl InterpErrorInfo<'_> { |
| pub fn print_backtrace(&mut self) { |
| if let Some(ref mut backtrace) = self.backtrace { |
| print_backtrace(&mut *backtrace); |
| } |
| } |
| } |
| |
| fn print_backtrace(backtrace: &mut Backtrace) { |
| backtrace.resolve(); |
| eprintln!("\n\nAn error occurred in miri:\n{:?}", backtrace); |
| } |
| |
| impl<'tcx> From<InterpError<'tcx>> for InterpErrorInfo<'tcx> { |
| fn from(kind: InterpError<'tcx>) -> Self { |
| let backtrace = match env::var("RUSTC_CTFE_BACKTRACE") { |
| // Matching `RUST_BACKTRACE` -- we treat "0" the same as "not present". |
| Ok(ref val) if val != "0" => { |
| let mut backtrace = Backtrace::new_unresolved(); |
| |
| if val == "immediate" { |
| // Print it now. |
| print_backtrace(&mut backtrace); |
| None |
| } else { |
| Some(Box::new(backtrace)) |
| } |
| }, |
| _ => None, |
| }; |
| InterpErrorInfo { |
| kind, |
| backtrace, |
| } |
| } |
| } |
| |
| #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)] |
| pub enum PanicInfo<O> { |
| Panic { |
| msg: Symbol, |
| line: u32, |
| col: u32, |
| file: Symbol, |
| }, |
| BoundsCheck { |
| len: O, |
| index: O, |
| }, |
| Overflow(mir::BinOp), |
| OverflowNeg, |
| DivisionByZero, |
| RemainderByZero, |
| GeneratorResumedAfterReturn, |
| GeneratorResumedAfterPanic, |
| } |
| |
| /// Type for MIR `Assert` terminator error messages. |
| pub type AssertMessage<'tcx> = PanicInfo<mir::Operand<'tcx>>; |
| |
| impl<O> PanicInfo<O> { |
| /// Getting a description does not require `O` to be printable, and does not |
| /// require allocation. |
| /// The caller is expected to handle `Panic` and `BoundsCheck` separately. |
| pub fn description(&self) -> &'static str { |
| use PanicInfo::*; |
| match self { |
| Overflow(mir::BinOp::Add) => |
| "attempt to add with overflow", |
| Overflow(mir::BinOp::Sub) => |
| "attempt to subtract with overflow", |
| Overflow(mir::BinOp::Mul) => |
| "attempt to multiply with overflow", |
| Overflow(mir::BinOp::Div) => |
| "attempt to divide with overflow", |
| Overflow(mir::BinOp::Rem) => |
| "attempt to calculate the remainder with overflow", |
| OverflowNeg => |
| "attempt to negate with overflow", |
| Overflow(mir::BinOp::Shr) => |
| "attempt to shift right with overflow", |
| Overflow(mir::BinOp::Shl) => |
| "attempt to shift left with overflow", |
| Overflow(op) => |
| bug!("{:?} cannot overflow", op), |
| DivisionByZero => |
| "attempt to divide by zero", |
| RemainderByZero => |
| "attempt to calculate the remainder with a divisor of zero", |
| GeneratorResumedAfterReturn => |
| "generator resumed after completion", |
| GeneratorResumedAfterPanic => |
| "generator resumed after panicking", |
| Panic { .. } | BoundsCheck { .. } => |
| bug!("Unexpected PanicInfo"), |
| } |
| } |
| } |
| |
| impl<O: fmt::Debug> fmt::Debug for PanicInfo<O> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| use PanicInfo::*; |
| match self { |
| Panic { ref msg, line, col, ref file } => |
| write!(f, "the evaluated program panicked at '{}', {}:{}:{}", msg, file, line, col), |
| BoundsCheck { ref len, ref index } => |
| write!(f, "index out of bounds: the len is {:?} but the index is {:?}", len, index), |
| _ => |
| write!(f, "{}", self.description()), |
| } |
| } |
| } |
| |
| /// Error information for when the program we executed turned out not to actually be a valid |
| /// program. This cannot happen in stand-alone Miri, but it can happen during CTFE/ConstProp |
| /// where we work on generic code or execution does not have all information available. |
| #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)] |
| pub enum InvalidProgramInfo<'tcx> { |
| /// Resolution can fail if we are in a too generic context. |
| TooGeneric, |
| /// Cannot compute this constant because it depends on another one |
| /// which already produced an error. |
| ReferencedConstant, |
| /// Abort in case type errors are reached. |
| TypeckError, |
| /// An error occurred during layout computation. |
| Layout(layout::LayoutError<'tcx>), |
| } |
| |
| impl fmt::Debug for InvalidProgramInfo<'tcx> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| use InvalidProgramInfo::*; |
| match self { |
| TooGeneric => |
| write!(f, "encountered overly generic constant"), |
| ReferencedConstant => |
| write!(f, "referenced constant has errors"), |
| TypeckError => |
| write!(f, "encountered constants with type errors, stopping evaluation"), |
| Layout(ref err) => |
| write!(f, "{}", err), |
| } |
| } |
| } |
| |
| /// Error information for when the program caused Undefined Behavior. |
| #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)] |
| pub enum UndefinedBehaviorInfo { |
| /// Free-form case. Only for errors that are never caught! |
| Ub(String), |
| /// Free-form case for experimental UB. Only for errors that are never caught! |
| UbExperimental(String), |
| /// Unreachable code was executed. |
| Unreachable, |
| } |
| |
| impl fmt::Debug for UndefinedBehaviorInfo { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| use UndefinedBehaviorInfo::*; |
| match self { |
| Ub(msg) | UbExperimental(msg) => |
| write!(f, "{}", msg), |
| Unreachable => |
| write!(f, "entered unreachable code"), |
| } |
| } |
| } |
| |
| /// Error information for when the program did something that might (or might not) be correct |
| /// to do according to the Rust spec, but due to limitations in the interpreter, the |
| /// operation could not be carried out. These limitations can differ between CTFE and the |
| /// Miri engine, e.g., CTFE does not support casting pointers to "real" integers. |
| /// |
| /// Currently, we also use this as fall-back error kind for errors that have not been |
| /// categorized yet. |
| #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)] |
| pub enum UnsupportedOpInfo<'tcx> { |
| /// Free-form case. Only for errors that are never caught! |
| Unsupported(String), |
| |
| // -- Everything below is not categorized yet -- |
| FunctionAbiMismatch(Abi, Abi), |
| FunctionArgMismatch(Ty<'tcx>, Ty<'tcx>), |
| FunctionRetMismatch(Ty<'tcx>, Ty<'tcx>), |
| FunctionArgCountMismatch, |
| UnterminatedCString(Pointer), |
| DanglingPointerDeref, |
| DoubleFree, |
| InvalidMemoryAccess, |
| InvalidFunctionPointer, |
| InvalidBool, |
| InvalidDiscriminant(ScalarMaybeUndef), |
| PointerOutOfBounds { |
| ptr: Pointer, |
| msg: CheckInAllocMsg, |
| allocation_size: Size, |
| }, |
| InvalidNullPointerUsage, |
| ReadPointerAsBytes, |
| ReadBytesAsPointer, |
| ReadForeignStatic, |
| InvalidPointerMath, |
| ReadUndefBytes(Size), |
| DeadLocal, |
| InvalidBoolOp(mir::BinOp), |
| UnimplementedTraitSelection, |
| CalledClosureAsFunction, |
| NoMirFor(String), |
| DerefFunctionPointer, |
| ExecuteMemory, |
| InvalidChar(u128), |
| OutOfTls, |
| TlsOutOfBounds, |
| AlignmentCheckFailed { |
| required: Align, |
| has: Align, |
| }, |
| ValidationFailure(String), |
| VtableForArgumentlessMethod, |
| ModifiedConstantMemory, |
| ModifiedStatic, |
| TypeNotPrimitive(Ty<'tcx>), |
| ReallocatedWrongMemoryKind(String, String), |
| DeallocatedWrongMemoryKind(String, String), |
| ReallocateNonBasePtr, |
| DeallocateNonBasePtr, |
| IncorrectAllocationInformation(Size, Size, Align, Align), |
| HeapAllocZeroBytes, |
| HeapAllocNonPowerOfTwoAlignment(u64), |
| ReadFromReturnPointer, |
| PathNotFound(Vec<String>), |
| } |
| |
| impl fmt::Debug for UnsupportedOpInfo<'tcx> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| use UnsupportedOpInfo::*; |
| match self { |
| PointerOutOfBounds { ptr, msg, allocation_size } => { |
| write!(f, "{} failed: pointer must be in-bounds at offset {}, \ |
| but is outside bounds of allocation {} which has size {}", |
| msg, ptr.offset.bytes(), ptr.alloc_id, allocation_size.bytes()) |
| }, |
| ValidationFailure(ref err) => { |
| write!(f, "type validation failed: {}", err) |
| } |
| NoMirFor(ref func) => write!(f, "no MIR for `{}`", func), |
| FunctionAbiMismatch(caller_abi, callee_abi) => |
| write!(f, "tried to call a function with ABI {:?} using caller ABI {:?}", |
| callee_abi, caller_abi), |
| FunctionArgMismatch(caller_ty, callee_ty) => |
| write!(f, "tried to call a function with argument of type {:?} \ |
| passing data of type {:?}", |
| callee_ty, caller_ty), |
| FunctionRetMismatch(caller_ty, callee_ty) => |
| write!(f, "tried to call a function with return type {:?} \ |
| passing return place of type {:?}", |
| callee_ty, caller_ty), |
| FunctionArgCountMismatch => |
| write!(f, "tried to call a function with incorrect number of arguments"), |
| ReallocatedWrongMemoryKind(ref old, ref new) => |
| write!(f, "tried to reallocate memory from `{}` to `{}`", old, new), |
| DeallocatedWrongMemoryKind(ref old, ref new) => |
| write!(f, "tried to deallocate `{}` memory but gave `{}` as the kind", old, new), |
| InvalidChar(c) => |
| write!(f, "tried to interpret an invalid 32-bit value as a char: {}", c), |
| AlignmentCheckFailed { required, has } => |
| write!(f, "tried to access memory with alignment {}, but alignment {} is required", |
| has.bytes(), required.bytes()), |
| TypeNotPrimitive(ty) => |
| write!(f, "expected primitive type, got {}", ty), |
| PathNotFound(ref path) => |
| write!(f, "cannot find path {:?}", path), |
| IncorrectAllocationInformation(size, size2, align, align2) => |
| 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 => |
| write!(f, "dangling pointer was dereferenced"), |
| DoubleFree => |
| write!(f, "tried to deallocate dangling pointer"), |
| InvalidFunctionPointer => |
| write!(f, "tried to use a function pointer after offsetting it"), |
| InvalidBool => |
| write!(f, "invalid boolean value read"), |
| InvalidNullPointerUsage => |
| write!(f, "invalid use of NULL pointer"), |
| ReadPointerAsBytes => |
| write!(f, "a raw memory access tried to access part of a pointer value as raw \ |
| bytes"), |
| ReadBytesAsPointer => |
| write!(f, "a memory access tried to interpret some bytes as a pointer"), |
| ReadForeignStatic => |
| write!(f, "tried to read from foreign (extern) static"), |
| InvalidPointerMath => |
| write!(f, "attempted to do invalid arithmetic on pointers that would leak base \ |
| addresses, e.g., comparing pointers into different allocations"), |
| DeadLocal => |
| write!(f, "tried to access a dead local variable"), |
| DerefFunctionPointer => |
| write!(f, "tried to dereference a function pointer"), |
| ExecuteMemory => |
| write!(f, "tried to treat a memory pointer as a function pointer"), |
| OutOfTls => |
| write!(f, "reached the maximum number of representable TLS keys"), |
| TlsOutOfBounds => |
| write!(f, "accessed an invalid (unallocated) TLS key"), |
| CalledClosureAsFunction => |
| write!(f, "tried to call a closure through a function pointer"), |
| VtableForArgumentlessMethod => |
| write!(f, "tried to call a vtable function without arguments"), |
| ModifiedConstantMemory => |
| write!(f, "tried to modify constant memory"), |
| ModifiedStatic => |
| write!(f, "tried to modify a static's initial value from another static's \ |
| initializer"), |
| ReallocateNonBasePtr => |
| write!(f, "tried to reallocate with a pointer not to the beginning of an \ |
| existing object"), |
| DeallocateNonBasePtr => |
| write!(f, "tried to deallocate with a pointer not to the beginning of an \ |
| existing object"), |
| HeapAllocZeroBytes => |
| write!(f, "tried to re-, de- or allocate zero bytes on the heap"), |
| ReadFromReturnPointer => |
| write!(f, "tried to read from the return pointer"), |
| UnimplementedTraitSelection => |
| write!(f, "there were unresolved type arguments during trait selection"), |
| InvalidBoolOp(_) => |
| write!(f, "invalid boolean operation"), |
| UnterminatedCString(_) => |
| write!(f, "attempted to get length of a null-terminated string, but no null \ |
| found before end of allocation"), |
| ReadUndefBytes(_) => |
| write!(f, "attempted to read undefined bytes"), |
| HeapAllocNonPowerOfTwoAlignment(_) => |
| write!(f, "tried to re-, de-, or allocate heap memory with alignment that is \ |
| not a power of two"), |
| Unsupported(ref msg) => |
| write!(f, "{}", msg), |
| } |
| } |
| } |
| |
| /// Error information for when the program exhausted the resources granted to it |
| /// by the interpreter. |
| #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)] |
| pub enum ResourceExhaustionInfo { |
| /// The stack grew too big. |
| StackFrameLimitReached, |
| /// The program ran into an infinite loop. |
| InfiniteLoop, |
| } |
| |
| impl fmt::Debug for ResourceExhaustionInfo { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| use ResourceExhaustionInfo::*; |
| match self { |
| StackFrameLimitReached => |
| write!(f, "reached the configured maximum number of stack frames"), |
| InfiniteLoop => |
| write!(f, "duplicate interpreter state observed here, const evaluation will never \ |
| terminate"), |
| } |
| } |
| } |
| |
| #[derive(Clone, RustcEncodable, RustcDecodable, HashStable)] |
| pub enum InterpError<'tcx> { |
| /// The program panicked. |
| Panic(PanicInfo<u64>), |
| /// The program caused undefined behavior. |
| UndefinedBehavior(UndefinedBehaviorInfo), |
| /// The program did something the interpreter does not support (some of these *might* be UB |
| /// but the interpreter is not sure). |
| Unsupported(UnsupportedOpInfo<'tcx>), |
| /// The program was invalid (ill-typed, not sufficiently monomorphized, ...). |
| InvalidProgram(InvalidProgramInfo<'tcx>), |
| /// The program exhausted the interpreter's resources (stack/heap too big, |
| /// execution takes too long, ..). |
| ResourceExhaustion(ResourceExhaustionInfo), |
| /// Not actually an interpreter error -- used to signal that execution has exited |
| /// with the given status code. Used by Miri, but not by CTFE. |
| Exit(i32), |
| } |
| |
| pub type InterpResult<'tcx, T = ()> = Result<T, InterpErrorInfo<'tcx>>; |
| |
| impl fmt::Display for InterpError<'_> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| // Forward `Display` to `Debug`. |
| write!(f, "{:?}", self) |
| } |
| } |
| |
| impl fmt::Debug for InterpError<'_> { |
| fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { |
| use InterpError::*; |
| match *self { |
| Unsupported(ref msg) => |
| write!(f, "{:?}", msg), |
| InvalidProgram(ref msg) => |
| write!(f, "{:?}", msg), |
| UndefinedBehavior(ref msg) => |
| write!(f, "{:?}", msg), |
| ResourceExhaustion(ref msg) => |
| write!(f, "{:?}", msg), |
| Panic(ref msg) => |
| write!(f, "{:?}", msg), |
| Exit(code) => |
| write!(f, "exited with status code {}", code), |
| } |
| } |
| } |