From b2ebf1c23f93886ba7d3738878f04e275add4ead Mon Sep 17 00:00:00 2001 From: Ralf Jung Date: Sun, 27 Aug 2023 18:12:34 +0200 Subject: const_eval and codegen: audit uses of is_zst --- compiler/rustc_codegen_ssa/src/base.rs | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) (limited to 'compiler/rustc_codegen_ssa/src/base.rs') diff --git a/compiler/rustc_codegen_ssa/src/base.rs b/compiler/rustc_codegen_ssa/src/base.rs index aa003e4e898..cd19885faa0 100644 --- a/compiler/rustc_codegen_ssa/src/base.rs +++ b/compiler/rustc_codegen_ssa/src/base.rs @@ -202,7 +202,7 @@ pub fn unsize_ptr<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( (src, unsized_info(bx, a, b, old_info)) } (&ty::Adt(def_a, _), &ty::Adt(def_b, _)) => { - assert_eq!(def_a, def_b); + assert_eq!(def_a, def_b); // implies same number of fields let src_layout = bx.cx().layout_of(src_ty); let dst_layout = bx.cx().layout_of(dst_ty); if src_ty == dst_ty { @@ -211,7 +211,8 @@ pub fn unsize_ptr<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( let mut result = None; for i in 0..src_layout.fields.count() { let src_f = src_layout.field(bx.cx(), i); - if src_f.is_zst() { + if src_f.is_1zst() { + // We are looking for the one non-1-ZST field; this is not it. continue; } @@ -272,13 +273,14 @@ pub fn coerce_unsized_into<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>( } (&ty::Adt(def_a, _), &ty::Adt(def_b, _)) => { - assert_eq!(def_a, def_b); + assert_eq!(def_a, def_b); // implies same number of fields for i in def_a.variant(FIRST_VARIANT).fields.indices() { let src_f = src.project_field(bx, i.as_usize()); let dst_f = dst.project_field(bx, i.as_usize()); if dst_f.layout.is_zst() { + // No data here, nothing to copy/coerce. continue; } -- cgit 1.4.1-3-g733a5