diff options
| -rw-r--r-- | src/librustc_mir/transform/check_unsafety.rs | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/src/librustc_mir/transform/check_unsafety.rs b/src/librustc_mir/transform/check_unsafety.rs index b124f8b1c0b..671ca355dbf 100644 --- a/src/librustc_mir/transform/check_unsafety.rs +++ b/src/librustc_mir/transform/check_unsafety.rs @@ -192,6 +192,12 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> { .ty(self.mir, self.tcx) .to_ty(self.tcx) .is_freeze(self.tcx, self.param_env, self.source_info.span); + // prevent + // * `&mut x.field` + // * `x.field = y;` + // * `&x.field` if `field`'s type has interior mutability + // because either of these would allow modifying the layout constrained field and + // insert values that violate the layout constraints. if context.is_mutating_use() || is_borrow_of_interior_mut { self.check_mut_borrowing_layout_constrained_field( place, context.is_mutating_use(), |