diff options
Diffstat (limited to 'compiler/rustc_mir_transform/src')
| -rw-r--r-- | compiler/rustc_mir_transform/src/check_unsafety.rs | 23 |
1 files changed, 8 insertions, 15 deletions
diff --git a/compiler/rustc_mir_transform/src/check_unsafety.rs b/compiler/rustc_mir_transform/src/check_unsafety.rs index 1f73b7da815..ded1f0462cb 100644 --- a/compiler/rustc_mir_transform/src/check_unsafety.rs +++ b/compiler/rustc_mir_transform/src/check_unsafety.rs @@ -219,22 +219,15 @@ impl<'tcx> Visitor<'tcx> for UnsafetyChecker<'_, 'tcx> { // We have to check the actual type of the assignment, as that determines if the // old value is being dropped. let assigned_ty = place.ty(&self.body.local_decls, self.tcx).ty; - // To avoid semver hazard, we only consider `Copy` and `ManuallyDrop` non-dropping. - let manually_drop = assigned_ty - .ty_adt_def() - .map_or(false, |adt_def| adt_def.is_manually_drop()); - let nodrop = manually_drop - || assigned_ty.is_copy_modulo_regions( - self.tcx.at(self.source_info.span), - self.param_env, + if assigned_ty.needs_drop( + self.tcx, + self.tcx.param_env(base_ty.ty_adt_def().unwrap().did()), + ) { + // This would be unsafe, but should be outright impossible since we reject such unions. + self.tcx.sess.delay_span_bug( + self.source_info.span, + "union fields that need dropping should be impossible", ); - if !nodrop { - self.require_unsafe( - UnsafetyViolationKind::General, - UnsafetyViolationDetails::AssignToDroppingUnionField, - ); - } else { - // write to non-drop union field, safe } } else { self.require_unsafe( |