diff options
| -rw-r--r-- | compiler/rustc_mir/src/borrow_check/type_check/mod.rs | 78 |
1 files changed, 41 insertions, 37 deletions
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/mod.rs b/compiler/rustc_mir/src/borrow_check/type_check/mod.rs index 543b7e7ebaa..42cd050abc5 100644 --- a/compiler/rustc_mir/src/borrow_check/type_check/mod.rs +++ b/compiler/rustc_mir/src/borrow_check/type_check/mod.rs @@ -1988,44 +1988,48 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> { // If the length is larger than 1, the repeat expression will need to copy the // element, so we require the `Copy` trait. if len.try_eval_usize(tcx, self.param_env).map_or(true, |len| len > 1) { - if let Operand::Move(_) = operand { - // While this is located in `nll::typeck` this error is not an NLL error, it's - // a required check to make sure that repeated elements implement `Copy`. - let span = body.source_info(location).span; - let ty = operand.ty(body, tcx); - if !self.infcx.type_is_copy_modulo_regions(self.param_env, ty, span) { - let ccx = ConstCx::new_with_param_env(tcx, body, self.param_env); - // To determine if `const_in_array_repeat_expressions` feature gate should - // be mentioned, need to check if the rvalue is promotable. - let should_suggest = - should_suggest_const_in_array_repeat_expressions_attribute( - &ccx, operand, - ); - debug!("check_rvalue: should_suggest={:?}", should_suggest); - - let def_id = body.source.def_id().expect_local(); - self.infcx.report_selection_error( - &traits::Obligation::new( - ObligationCause::new( - span, - self.tcx().hir().local_def_id_to_hir_id(def_id), - traits::ObligationCauseCode::RepeatVec(should_suggest), - ), - self.param_env, - ty::Binder::bind(ty::TraitRef::new( - self.tcx().require_lang_item( - LangItem::Copy, - Some(self.last_span), + match operand { + Operand::Copy(..) | Operand::Constant(..) => { + // These are always okay: direct use of a const, or a value that can evidently be copied. + } + Operand::Move(_) => { + // Make sure that repeated elements implement `Copy`. + let span = body.source_info(location).span; + let ty = operand.ty(body, tcx); + if !self.infcx.type_is_copy_modulo_regions(self.param_env, ty, span) { + let ccx = ConstCx::new_with_param_env(tcx, body, self.param_env); + // To determine if `const_in_array_repeat_expressions` feature gate should + // be mentioned, need to check if the rvalue is promotable. + let should_suggest = + should_suggest_const_in_array_repeat_expressions_attribute( + &ccx, operand, + ); + debug!("check_rvalue: should_suggest={:?}", should_suggest); + + let def_id = body.source.def_id().expect_local(); + self.infcx.report_selection_error( + &traits::Obligation::new( + ObligationCause::new( + span, + self.tcx().hir().local_def_id_to_hir_id(def_id), + traits::ObligationCauseCode::RepeatVec(should_suggest), ), - tcx.mk_substs_trait(ty, &[]), - )) - .without_const() - .to_predicate(self.tcx()), - ), - &traits::SelectionError::Unimplemented, - false, - false, - ); + self.param_env, + ty::Binder::bind(ty::TraitRef::new( + self.tcx().require_lang_item( + LangItem::Copy, + Some(self.last_span), + ), + tcx.mk_substs_trait(ty, &[]), + )) + .without_const() + .to_predicate(self.tcx()), + ), + &traits::SelectionError::Unimplemented, + false, + false, + ); + } } } } |