bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Migrate mir_build's borrow conflicts

Browse source
This commit is contained in:
mejrs 2023-01-17 13:48:43 +01:00
parent ae4d89dfb5
commit 6fe4cf795b
11 changed files with 303 additions and 274 deletions
Download patch file Download diff file Expand all files Collapse all files

50
compiler/rustc_mir_build/src/errors.rs
View file

@ -600,32 +600,56 @@ pub struct BorrowOfMovedValue<'tcx> {
pub struct MultipleMutBorrows {
#[primary_span]
pub span: Span,
#[label]
pub binding_span: Span,
#[subdiagnostic]
pub occurences: Vec<MultipleMutBorrowOccurence>,
pub name: Ident,
pub occurences: Vec<Conflict>,
}
#[derive(Diagnostic)]
#[diag(mir_build_already_borrowed)]
pub struct AlreadyBorrowed {
#[primary_span]
pub span: Span,
#[subdiagnostic]
pub occurences: Vec<Conflict>,
}
#[derive(Diagnostic)]
#[diag(mir_build_already_mut_borrowed)]
pub struct AlreadyMutBorrowed {
#[primary_span]
pub span: Span,
#[subdiagnostic]
pub occurences: Vec<Conflict>,
}
#[derive(Diagnostic)]
#[diag(mir_build_moved_while_borrowed)]
pub struct MovedWhileBorrowed {
#[primary_span]
pub span: Span,
#[subdiagnostic]
pub occurences: Vec<Conflict>,
}
#[derive(Subdiagnostic)]
pub enum MultipleMutBorrowOccurence {
#[label(mutable_borrow)]
Mutable {
pub enum Conflict {
#[label(mir_build_mutable_borrow)]
Mut {
#[primary_span]
span: Span,
name_mut: Ident,
name: Ident,
},
#[label(immutable_borrow)]
Immutable {
#[label(mir_build_borrow)]
Ref {
#[primary_span]
span: Span,
name_immut: Ident,
name: Ident,
},
#[label(moved)]
#[label(mir_build_moved)]
Moved {
#[primary_span]
span: Span,
name_moved: Ident,
name: Ident,
},
}

79
compiler/rustc_mir_build/src/thir/pattern/check_match.rs
View file

@ -914,58 +914,55 @@ fn check_borrow_conflicts_in_at_patterns(cx: &MatchVisitor<'_, '_, '_>, pat: &Pa
sub.each_binding(|_, hir_id, span, name| {
match typeck_results.extract_binding_mode(sess, hir_id, span) {
Some(ty::BindByReference(mut_inner)) => match (mut_outer, mut_inner) {
(Mutability::Not, Mutability::Not) => {} // Both sides are `ref`.
(Mutability::Mut, Mutability::Mut) => conflicts_mut_mut.push((span, name)), // 2x `ref mut`.
_ => conflicts_mut_ref.push((span, name)), // `ref` + `ref mut` in either direction.
// Both sides are `ref`.
(Mutability::Not, Mutability::Not) => {}
// 2x `ref mut`.
(Mutability::Mut, Mutability::Mut) => {
conflicts_mut_mut.push(Conflict::Mut { span, name })
}
(Mutability::Not, Mutability::Mut) => {
conflicts_mut_ref.push(Conflict::Mut { span, name })
}
(Mutability::Mut, Mutability::Not) => {
conflicts_mut_ref.push(Conflict::Ref { span, name })
}
},
Some(ty::BindByValue(_)) if is_binding_by_move(cx, hir_id) => {
conflicts_move.push((span, name)) // `ref mut?` + by-move conflict.
conflicts_move.push(Conflict::Moved { span, name }) // `ref mut?` + by-move conflict.
}
Some(ty::BindByValue(_)) | None => {} // `ref mut?` + by-copy is fine.
}
});
// Report errors if any.
if !conflicts_mut_mut.is_empty() {
// Report mutability conflicts for e.g. `ref mut x @ Some(ref mut y)`.
let mut occurences = vec![];
let report_mut_mut = !conflicts_mut_mut.is_empty();
let report_mut_ref = !conflicts_mut_ref.is_empty();
let report_move_conflict = !conflicts_move.is_empty();
for (span, name_mut) in conflicts_mut_mut {
occurences.push(MultipleMutBorrowOccurence::Mutable { span, name_mut });
}
for (span, name_immut) in conflicts_mut_ref {
occurences.push(MultipleMutBorrowOccurence::Immutable { span, name_immut });
}
for (span, name_moved) in conflicts_move {
occurences.push(MultipleMutBorrowOccurence::Moved { span, name_moved });
}
sess.emit_err(MultipleMutBorrows { span: pat.span, binding_span, occurences, name });
} else if !conflicts_mut_ref.is_empty() {
let mut occurences = match mut_outer {
Mutability::Mut => vec![Conflict::Mut { span: binding_span, name }],
Mutability::Not => vec![Conflict::Ref { span: binding_span, name }],
};
occurences.extend(conflicts_mut_mut);
occurences.extend(conflicts_mut_ref);
occurences.extend(conflicts_move);
// Report errors if any.
if report_mut_mut {
// Report mutability conflicts for e.g. `ref mut x @ Some(ref mut y)`.
sess.emit_err(MultipleMutBorrows { span: pat.span, occurences });
} else if report_mut_ref {
// Report mutability conflicts for e.g. `ref x @ Some(ref mut y)` or the converse.
let (primary, also) = match mut_outer {
Mutability::Mut => ("mutable", "immutable"),
Mutability::Not => ("immutable", "mutable"),
match mut_outer {
Mutability::Mut => {
sess.emit_err(AlreadyMutBorrowed { span: pat.span, occurences });
}
Mutability::Not => {
sess.emit_err(AlreadyBorrowed { span: pat.span, occurences });
}
};
let msg =
format!("cannot borrow value as {} because it is also borrowed as {}", also, primary);
let mut err = sess.struct_span_err(pat.span, &msg);
err.span_label(binding_span, format!("{} borrow, by `{}`, occurs here", primary, name));
for (span, name) in conflicts_mut_ref {
err.span_label(span, format!("{} borrow, by `{}`, occurs here", also, name));
}
for (span, name) in conflicts_move {
err.span_label(span, format!("also moved into `{}` here", name));
}
err.emit();
} else if !conflicts_move.is_empty() {
} else if report_move_conflict {
// Report by-ref and by-move conflicts, e.g. `ref x @ y`.
let mut err =
sess.struct_span_err(pat.span, "cannot move out of value because it is borrowed");
err.span_label(binding_span, format!("value borrowed, by `{}`, here", name));
for (span, name) in conflicts_move {
err.span_label(span, format!("value moved into `{}` here", name));
}
err.emit();
sess.emit_err(MovedWhileBorrowed { span: pat.span, occurences });
}
}