diff options
| -rw-r--r-- | src/librustc_mir/borrow_check/mod.rs | 44 |
1 files changed, 28 insertions, 16 deletions
diff --git a/src/librustc_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs index a8af5f5d32b..0f4585c8c04 100644 --- a/src/librustc_mir/borrow_check/mod.rs +++ b/src/librustc_mir/borrow_check/mod.rs @@ -655,8 +655,9 @@ enum WriteKind { /// - Take flow state into consideration in `is_assignable()` for local variables #[derive(Copy, Clone, PartialEq, Eq, Debug)] enum LocalMutationIsAllowed { + Move, Yes, - No, + No } #[derive(Copy, Clone)] @@ -946,7 +947,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> { context, (place, span), (Deep, Write(WriteKind::Move)), - LocalMutationIsAllowed::Yes, + LocalMutationIsAllowed::Move, flow_state, ); @@ -1368,7 +1369,8 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> { let local = &self.mir.local_decls[local]; match local.mutability { Mutability::Not => match is_local_mutation_allowed { - LocalMutationIsAllowed::Yes => Ok(()), + LocalMutationIsAllowed::Yes | + LocalMutationIsAllowed::Move => Ok(()), LocalMutationIsAllowed::No => Err(place), }, Mutability::Mut => Ok(()), @@ -1393,10 +1395,14 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> { // Mutably borrowed data is mutable, but only if we have a // unique path to the `&mut` hir::MutMutable => { - if self.is_upvar_field_projection(&proj.base).is_some() { - self.is_mutable(&proj.base, is_local_mutation_allowed) - } else { - self.is_unique(&proj.base) + match self.is_upvar_field_projection(&proj.base) { + Some(field) if { + self.mir.upvar_decls[field.index()].by_ref + } => { + self.is_mutable(&proj.base, + is_local_mutation_allowed) + } + _ => self.is_unique(&proj.base) } } } @@ -1412,7 +1418,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> { } // `Box<T>` owns its content, so mutable if its location is mutable _ if base_ty.is_box() => { - self.is_mutable(&proj.base, LocalMutationIsAllowed::No) + self.is_mutable(&proj.base, is_local_mutation_allowed) } // Deref should only be for reference, pointers or boxes _ => bug!("Deref of unexpected type: {:?}", base_ty), @@ -1429,14 +1435,17 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> { if let Some(field) = field_projection { let decl = &self.mir.upvar_decls[field.index()]; - - return match decl.mutability { - Mutability::Mut => self.is_unique(&proj.base), - Mutability::Not => Err(place), + debug!("decl.mutability={:?} local_mutation_is_allowed={:?} place={:?}", + decl, is_local_mutation_allowed, place); + return match (decl.mutability, is_local_mutation_allowed) { + (Mutability::Not, LocalMutationIsAllowed::No) | + (Mutability::Not, LocalMutationIsAllowed::Yes) => Err(place), + (Mutability::Not, LocalMutationIsAllowed::Move) | + (Mutability::Mut, _) => self.is_unique(&proj.base), }; } - self.is_mutable(&proj.base, LocalMutationIsAllowed::No) + self.is_mutable(&proj.base, is_local_mutation_allowed) } } } @@ -1450,9 +1459,12 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> { // Local variables are unique Ok(()) } - Place::Static(..) => { - // Static variables are not - Err(place) + Place::Static(ref static_) => { + if !self.tcx.is_static_mut(static_.def_id) { + Err(place) + } else { + Ok(()) + } } Place::Projection(ref proj) => { match proj.elem { |