rust: negative polarity removes restrictions on validation of impl bl…

…ocks Negative polarity means we can just ignore if any trait items are not implemented. Fxies #3030 gcc/rust/ChangeLog: * hir/rust-ast-lower-item.cc (ASTLoweringItem::visit): the polarity was reversed * typecheck/rust-hir-type-check-item.cc: check the polarity gcc/testsuite/ChangeLog: * rust/compile/nr2/exclude: nr2 cant handle this * rust/compile/issue-3030.rs: New test. Signed-off-by: Philip Herron <[email protected]>
Rust-GCC · Sep 20, 2024 · 9e7b042 · 9e7b042
1 parent d65c6c9
commit 9e7b042
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Showing 4 changed files with 21 additions and 3 deletions.
diff --git a/gcc/rust/hir/rust-ast-lower-item.cc b/gcc/rust/hir/rust-ast-lower-item.cc
@@ -690,8 +690,8 @@ ASTLoweringItem::visit (AST::TraitImpl &impl_block)
     }
 
   BoundPolarity polarity = impl_block.is_exclam ()
-			     ? BoundPolarity::RegularBound
-			     : BoundPolarity::NegativeBound;
+			     ? BoundPolarity::NegativeBound
+			     : BoundPolarity::RegularBound;
   HIR::ImplBlock *hir_impl_block = new HIR::ImplBlock (
     mapping, std::move (impl_items), std::move (generic_params),
     std::unique_ptr<HIR::Type> (impl_type),

diff --git a/gcc/rust/typecheck/rust-hir-type-check-item.cc b/gcc/rust/typecheck/rust-hir-type-check-item.cc
@@ -734,7 +734,8 @@ TypeCheckItem::validate_trait_impl_block (
   bool impl_block_missing_trait_items
     = !specified_bound.is_error ()
       && trait_reference->size () != trait_item_refs.size ();
-  if (impl_block_missing_trait_items)
+  if (impl_block_missing_trait_items
+      && impl_block.get_polarity () == BoundPolarity::RegularBound)
     {
       // filter the missing impl_items
       std::vector<std::reference_wrapper<const TraitItemReference>>

diff --git a/gcc/testsuite/rust/compile/issue-3030.rs b/gcc/testsuite/rust/compile/issue-3030.rs
@@ -0,0 +1,16 @@
+#![feature(negative_impls)]
+
+#[lang = "sized"]
+pub trait Sized {}
+
+pub trait Deref {}
+
+pub trait DerefMut: Deref {
+    type Target;
+
+    /// Mutably dereferences the value.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    fn deref_mut(&mut self) -> &mut Self::Target;
+}
+
+impl<T: ?Sized> !DerefMut for &T {}
diff --git a/gcc/testsuite/rust/compile/nr2/exclude b/gcc/testsuite/rust/compile/nr2/exclude
@@ -291,3 +291,4 @@ unknown-associated-item.rs
 box_syntax_feature_gate.rs
 dropck_eyepatch_feature_gate.rs
 inline_asm_parse_output_operand.rs
+issue-3030.rs