gccrs: Add feature gate for box syntax

The box syntax is experimental even though it is used in the standard
library. It should be feature gated to prevent anyone from using it in
stable rust.

gcc/rust/ChangeLog:

	* checks/errors/rust-feature-gate.cc (FeatureGate::visit): Allow
	visitor recursion in functions. Also add the gate for the box syntax.
	* checks/errors/rust-feature-gate.h: Remove several recursion fences
	in the feature gate visitor.
	* checks/errors/rust-feature.cc (Feature::create): Add a new feature.
	(Feature::as_name): Likewise.
	* checks/errors/rust-feature.h: Add box_syntax gate.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

diff --git a/gcc/rust/checks/errors/rust-feature-gate.cc b/gcc/rust/checks/errors/rust-feature-gate.cc
index 6ef2d1f710fb8c2103f48ea48f2274ea8ffeee3a..69348cb90e859ee37e7490c217f2b172ac760cbd 100644 (file)
--- a/gcc/rust/checks/errors/rust-feature-gate.cc
+++ b/gcc/rust/checks/errors/rust-feature-gate.cc
@@ -134,6 +134,8 @@ FeatureGate::visit (AST::Function &function)
 {
   if (!function.is_external ())
     check_rustc_attri (function.get_outer_attrs ());
+
+  AST::DefaultASTVisitor::visit (function);
 }
 
 void
@@ -153,4 +155,13 @@ FeatureGate::visit (AST::TraitImpl &impl)
          "negative_impls are not yet implemented");
 };
 
+void
+FeatureGate::visit (AST::BoxExpr &expr)
+{
+  gate (
+    Feature::Name::BOX_SYNTAX, expr.get_locus (),
+    "box expression syntax is experimental; you can call `Box::new` instead");
+  AST::DefaultASTVisitor::visit (expr);
+}
+
 } // namespace Rust

diff --git a/gcc/rust/checks/errors/rust-feature-gate.h b/gcc/rust/checks/errors/rust-feature-gate.h
index de48f22559871f2886907274733e00c0cc17fdf1..bef7cf1b449c1f020f1816335c0108d09ed71417 100644 (file)
--- a/gcc/rust/checks/errors/rust-feature-gate.h
+++ b/gcc/rust/checks/errors/rust-feature-gate.h
@@ -81,7 +81,6 @@ public:
   void visit (AST::MethodCallExpr &expr) override {}
   void visit (AST::FieldAccessExpr &expr) override {}
   void visit (AST::ClosureExprInner &expr) override {}
-  void visit (AST::BlockExpr &expr) override {}
   void visit (AST::ClosureExprInnerTyped &expr) override {}
   void visit (AST::ContinueExpr &expr) override {}
   void visit (AST::BreakExpr &expr) override {}
@@ -92,6 +91,7 @@ public:
   void visit (AST::RangeFromToInclExpr &expr) override {}
   void visit (AST::RangeToInclExpr &expr) override {}
   void visit (AST::ReturnExpr &expr) override {}
+  void visit (AST::BoxExpr &expr) override;
   void visit (AST::UnsafeBlockExpr &expr) override {}
   void visit (AST::LoopExpr &expr) override {}
   void visit (AST::WhileLoopExpr &expr) override {}
@@ -166,7 +166,6 @@ public:
   void visit (AST::SlicePattern &pattern) override {}
   void visit (AST::AltPattern &pattern) override {}
   void visit (AST::EmptyStmt &stmt) override {}
-  void visit (AST::LetStmt &stmt) override {}
   void visit (AST::ExprStmt &stmt) override {}
   void visit (AST::TraitBound &bound) override {}
   void visit (AST::ImplTraitType &type) override {}

diff --git a/gcc/rust/checks/errors/rust-feature.cc b/gcc/rust/checks/errors/rust-feature.cc
index 1e11bd541a58d9f21a23c4a25450e75814f74c70..f993bbb7245b40d3ae7892e4a5d6c4ae936c9dd5 100644 (file)
--- a/gcc/rust/checks/errors/rust-feature.cc
+++ b/gcc/rust/checks/errors/rust-feature.cc
@@ -45,6 +45,9 @@ Feature::create (Feature::Name name)
     case Feature::Name::NEGATIVE_IMPLS:
       return Feature (Feature::Name::NEGATIVE_IMPLS, Feature::State::ACTIVE,
                      "negative_impls", "1.0.0", 68318, tl::nullopt, "");
+    case Feature::Name::BOX_SYNTAX:
+      return Feature (Feature::Name::BOX_SYNTAX, Feature::State::ACTIVE,
+                     "box_syntax", "1.0.0", 49733, tl::nullopt, "");
     default:
       rust_unreachable ();
     }
@@ -62,6 +65,7 @@ const std::map<std::string, Feature::Name> Feature::name_hash_map = {
   {"extern_types", Feature::Name::EXTERN_TYPES},
   {"lang_items", Feature::Name::LANG_ITEMS},
   {"no_core", Feature::Name::NO_CORE},
+  {"box_syntax", Feature::Name::BOX_SYNTAX},
 }; // namespace Rust
 
 tl::optional<Feature::Name>
@@ -73,4 +77,4 @@ Feature::as_name (const std::string &name)
   return tl::nullopt;
 }
 
-} // namespace Rust
\ No newline at end of file
+} // namespace Rust

diff --git a/gcc/rust/checks/errors/rust-feature.h b/gcc/rust/checks/errors/rust-feature.h
index 611dceaa2c9445e4847deda951d610abed1daee8..736d97e1cde6eeeb07b13676991510b5e31652e0 100644 (file)
--- a/gcc/rust/checks/errors/rust-feature.h
+++ b/gcc/rust/checks/errors/rust-feature.h
@@ -46,6 +46,7 @@ public:
     EXTERN_TYPES,
     LANG_ITEMS,
     NO_CORE,
+    BOX_SYNTAX,
   };
 
   const std::string &as_string () { return m_name_str; }
@@ -79,4 +80,4 @@ private:
 };
 
 } // namespace Rust
-#endif
\ No newline at end of file
+#endif