diff options
Diffstat (limited to 'compiler/rustc_codegen_ssa/src')
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/mir/place.rs | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/compiler/rustc_codegen_ssa/src/mir/place.rs b/compiler/rustc_codegen_ssa/src/mir/place.rs index 2b8fa3be56d..17cfb6c5dfb 100644 --- a/compiler/rustc_codegen_ssa/src/mir/place.rs +++ b/compiler/rustc_codegen_ssa/src/mir/place.rs @@ -441,11 +441,19 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { .find(|elem| matches!(elem.1, mir::ProjectionElem::Deref)) { base = elem.0 + 1; - self.codegen_consume( + let cg_base = self.codegen_consume( bx, mir::PlaceRef { projection: &place_ref.projection[..elem.0], ..place_ref }, - ) - .deref(bx.cx()) + ); + + // a box with a non-zst allocator should not be directly dereferenced + if cg_base.layout.ty.is_box() && !cg_base.layout.field(cx, 1).is_zst() { + let ptr = cg_base.extract_field(bx, 0).extract_field(bx, 0); + + ptr.deref(bx.cx()) + } else { + cg_base.deref(bx.cx()) + } } else { bug!("using operand local {:?} as place", place_ref); } @@ -454,10 +462,8 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> { for elem in place_ref.projection[base..].iter() { cg_base = match elem.clone() { mir::ProjectionElem::Deref => { - // custom allocators can change box's abi, making it unable to be derefed directly - if cg_base.layout.ty.is_box() - && matches!(cg_base.layout.abi, Abi::Aggregate { .. } | Abi::Uninhabited) - { + // a box with a non-zst allocator should not be directly dereferenced + if cg_base.layout.ty.is_box() && !cg_base.layout.field(cx, 1).is_zst() { let ptr = cg_base.project_field(bx, 0).project_field(bx, 0); bx.load_operand(ptr).deref(bx.cx()) |