diff options
| -rw-r--r-- | compiler/rustc_passes/src/check_const.rs | 44 | ||||
| -rw-r--r-- | src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-fail.rs (renamed from src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn.rs) | 6 | ||||
| -rw-r--r-- | src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-fail.stderr (renamed from src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn.stderr) | 6 | ||||
| -rw-r--r-- | src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-pass.rs | 34 |
4 files changed, 64 insertions, 26 deletions
diff --git a/compiler/rustc_passes/src/check_const.rs b/compiler/rustc_passes/src/check_const.rs index 4a82252a32b..a0ceb567f25 100644 --- a/compiler/rustc_passes/src/check_const.rs +++ b/compiler/rustc_passes/src/check_const.rs @@ -8,7 +8,6 @@ //! through, but errors for structured control flow in a `const` should be emitted here. use rustc_attr as attr; -use rustc_data_structures::stable_set::FxHashSet; use rustc_errors::struct_span_err; use rustc_hir as hir; use rustc_hir::def_id::LocalDefId; @@ -83,30 +82,39 @@ impl<'tcx> hir::itemlikevisit::ItemLikeVisitor<'tcx> for CheckConstTraitVisitor< let _: Option<_> = try { if let hir::ItemKind::Impl(ref imp) = item.kind { if let hir::Constness::Const = imp.constness { - let did = imp.of_trait.as_ref()?.trait_def_id()?; - let mut to_implement = FxHashSet::default(); - - for did in self.tcx.associated_item_def_ids(did) { + let trait_def_id = imp.of_trait.as_ref()?.trait_def_id()?; + let ancestors = self + .tcx + .trait_def(trait_def_id) + .ancestors(self.tcx, item.def_id.to_def_id()) + .ok()?; + let mut to_implement = Vec::new(); + + for trait_item in self.tcx.associated_items(trait_def_id).in_definition_order() + { if let ty::AssocItem { kind: ty::AssocKind::Fn, ident, defaultness, .. - } = self.tcx.associated_item(*did) + } = trait_item { // we can ignore functions that do not have default bodies: // if those are unimplemented it will be catched by typeck. - if defaultness.has_value() - && !self.tcx.has_attr(*did, sym::default_method_body_is_const) + if !defaultness.has_value() + || self + .tcx + .has_attr(trait_item.def_id, sym::default_method_body_is_const) { - to_implement.insert(ident); + continue; } - } - } - for it in imp - .items - .iter() - .filter(|it| matches!(it.kind, hir::AssocItemKind::Fn { .. })) - { - to_implement.remove(&it.ident); + let is_implemented = ancestors + .leaf_def(self.tcx, trait_item.ident, trait_item.kind) + .map(|node_item| !node_item.defining_node.is_from_trait()) + .unwrap_or(false); + + if !is_implemented { + to_implement.push(ident.to_string()); + } + } } // all nonconst trait functions (not marked with #[default_method_body_is_const]) @@ -118,7 +126,7 @@ impl<'tcx> hir::itemlikevisit::ItemLikeVisitor<'tcx> for CheckConstTraitVisitor< item.span, "const trait implementations may not use non-const default functions", ) - .note(&format!("`{}` not implemented", to_implement.into_iter().map(|id| id.to_string()).collect::<Vec<_>>().join("`, `"))) + .note(&format!("`{}` not implemented", to_implement.join("`, `"))) .emit(); } } diff --git a/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn.rs b/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-fail.rs index 59de9e95719..8eefb375b8c 100644 --- a/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn.rs +++ b/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-fail.rs @@ -1,4 +1,5 @@ #![feature(const_trait_impl)] +#![feature(const_fn_trait_bound)] trait Tr { fn req(&self); @@ -18,11 +19,6 @@ impl const Tr for S { fn req(&self) {} } //~^^ ERROR const trait implementations may not use non-const default functions -impl const Tr for u8 { - fn req(&self) {} - fn prov(&self) {} -} - impl const Tr for u16 { fn prov(&self) {} fn default() {} diff --git a/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn.stderr b/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-fail.stderr index 5301e0ad12e..a0916797041 100644 --- a/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn.stderr +++ b/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-fail.stderr @@ -1,5 +1,5 @@ error: const trait implementations may not use non-const default functions - --> $DIR/impl-with-default-fn.rs:17:1 + --> $DIR/impl-with-default-fn-fail.rs:18:1 | LL | / impl const Tr for S { LL | | fn req(&self) {} @@ -9,7 +9,7 @@ LL | | } = note: `prov` not implemented error: const trait implementations may not use non-const default functions - --> $DIR/impl-with-default-fn.rs:32:1 + --> $DIR/impl-with-default-fn-fail.rs:28:1 | LL | / impl const Tr for u32 { LL | | fn req(&self) {} @@ -20,7 +20,7 @@ LL | | } = note: `prov` not implemented error[E0046]: not all trait items implemented, missing: `req` - --> $DIR/impl-with-default-fn.rs:26:1 + --> $DIR/impl-with-default-fn-fail.rs:22:1 | LL | fn req(&self); | -------------- `req` from trait diff --git a/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-pass.rs b/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-pass.rs new file mode 100644 index 00000000000..ba3fec0882b --- /dev/null +++ b/src/test/ui/rfc-2632-const-trait-impl/impl-with-default-fn-pass.rs @@ -0,0 +1,34 @@ +// check-pass + +#![feature(const_trait_impl)] +#![feature(const_fn_trait_bound)] + +trait Tr { + fn req(&self); + + fn prov(&self) { + println!("lul"); + self.req(); + } + + #[default_method_body_is_const] + fn default() {} +} + +impl const Tr for u8 { + fn req(&self) {} + fn prov(&self) {} +} + +macro_rules! impl_tr { + ($ty: ty) => { + impl const Tr for $ty { + fn req(&self) {} + fn prov(&self) {} + } + } +} + +impl_tr!(u64); + +fn main() {} |