Marking live symbol for struct construction.

Comment iterate_type_ribs of UnusedScan in order to resolve multiple struct unused report.

7 files changed, 88 insertions, 38 deletions

diff --git a/gcc/rust/lint/rust-lint-marklive.cc b/gcc/rust/lint/rust-lint-marklive.cc
index 0d4963c..5cdb5d4 100644
--- a/gcc/rust/lint/rust-lint-marklive.cc
+++ b/gcc/rust/lint/rust-lint-marklive.cc
@@ -91,31 +91,39 @@ MarkLive::go (HIR::Crate &crate)
 void
 MarkLive::visit (HIR::PathInExpression &expr)
 {
-  NodeId ast_node_id = expr.get_mappings ().get_nodeid ();
-  NodeId ref_node_id = UNKNOWN_NODEID;
-  if (resolver->lookup_resolved_name (ast_node_id, &ref_node_id))
-    {
-      Resolver::Definition def;
-      if (!resolver->lookup_definition (ref_node_id, &def))
-	{
-	  rust_error_at (expr.get_locus (),
-			 "unknown reference for resolved name");
-	  return;
-	}
-      ref_node_id = def.parent;
-      HirId ref;
-      if (!mappings->lookup_node_to_hir (expr.get_mappings ().get_crate_num (),
-					 ref_node_id, &ref))
-	{
-	  rust_error_at (expr.get_locus (), "reverse lookup failure");
-	  return;
-	}
-      if (scannedSymbols.find (ref) == scannedSymbols.end ())
-	{
-	  worklist.push_back (ref);
-	}
-      liveSymbols.emplace (ref);
-    }
+  expr.iterate_path_segments ([&] (HIR::PathExprSegment &seg) -> bool {
+    NodeId ast_node_id = seg.get_mappings ().get_nodeid ();
+    NodeId ref_node_id = UNKNOWN_NODEID;
+    HirId ref;
+    if (resolver->lookup_resolved_name (ast_node_id, &ref_node_id))
+      {
+	Resolver::Definition def;
+	if (!resolver->lookup_definition (ref_node_id, &def))
+	  {
+	    rust_error_at (seg.get_locus (),
+			   "unknown reference for resolved name");
+	    return false;
+	  }
+	ref_node_id = def.parent;
+      }
+    else if (!resolver->lookup_resolved_type (ast_node_id, &ref_node_id))
+      {
+	return false;
+      }
+
+    if (!mappings->lookup_node_to_hir (seg.get_mappings ().get_crate_num (),
+				       ref_node_id, &ref))
+      {
+	rust_error_at (seg.get_locus (), "reverse lookup failure");
+	return false;
+      }
+    if (scannedSymbols.find (ref) == scannedSymbols.end ())
+      {
+	worklist.push_back (ref);
+      }
+    liveSymbols.emplace (ref);
+    return true;
+  });
 }
 
 void
diff --git a/gcc/rust/lint/rust-lint-marklive.h b/gcc/rust/lint/rust-lint-marklive.h
index d34587d..673639a 100644
--- a/gcc/rust/lint/rust-lint-marklive.h
+++ b/gcc/rust/lint/rust-lint-marklive.h
@@ -201,12 +201,19 @@ public:
       }
   }
 
+  void visit (HIR::StructExprStruct &stct) override
+  {
+    stct.get_struct_name ().accept_vis (*this);
+  }
+
   void visit (HIR::StructExprStructFields &stct) override
   {
     stct.iterate ([&] (HIR::StructExprField *field) -> bool {
       field->accept_vis (*this);
       return true;
     });
+
+    stct.get_struct_name ().accept_vis (*this);
     if (stct.has_struct_base ())
       {
 	stct.struct_base->base_struct.get ()->accept_vis (*this);
diff --git a/gcc/rust/lint/rust-lint-scan-deadcode.h b/gcc/rust/lint/rust-lint-scan-deadcode.h
index 264b753..1dee18a 100644
--- a/gcc/rust/lint/rust-lint-scan-deadcode.h
+++ b/gcc/rust/lint/rust-lint-scan-deadcode.h
@@ -46,20 +46,34 @@ public:
   void visit (HIR::Function &function) override
   {
     HirId hirId = function.get_mappings ().get_hirid ();
-    if (live_symbols.find (hirId) == live_symbols.end ())
-      {
-	rust_warning_at (function.get_locus (), 0,
-			 "function is never used: %<%s%>",
-			 function.get_function_name ().c_str ());
-	return;
-      }
+    warning (hirId, function.get_locus (), "function",
+	     function.get_function_name (), "used");
+  }
+
+  void visit (HIR::StructStruct &stct) override
+  {
+    HirId hirId = stct.get_mappings ().get_hirid ();
+    warning (hirId, stct.get_locus (), "struct", stct.get_identifier (),
+	     "constructed");
   }
 
 private:
   std::set<HirId> live_symbols;
-  // std::set<HirId> dead_codes;
+  Resolver::Resolver *resolver;
 
-  ScanDeadcode (std::set<HirId> &live_symbols) : live_symbols (live_symbols){};
+  ScanDeadcode (std::set<HirId> &live_symbols)
+    : live_symbols (live_symbols), resolver (Resolver::Resolver::get ()){};
+
+  void warning (HirId hirId, Location loc, const std::string &span,
+		const std::string &name, const std::string &participle) const
+  {
+    if (live_symbols.find (hirId) == live_symbols.end ())
+      {
+	rust_warning_at (loc, 0, "%s is never %s: %<%s%>", span.c_str (),
+			 participle.c_str (), name.c_str ());
+	return;
+      }
+  }
 };
 
 } // namespace Analysis
diff --git a/gcc/rust/resolve/rust-ast-resolve-unused.h b/gcc/rust/resolve/rust-ast-resolve-unused.h
index 432776c..f60093c 100644
--- a/gcc/rust/resolve/rust-ast-resolve-unused.h
+++ b/gcc/rust/resolve/rust-ast-resolve-unused.h
@@ -19,6 +19,7 @@
 #ifndef RUST_AST_RESOLVE_UNUSED_H
 #define RUST_AST_RESOLVE_UNUSED_H
 
+#include "rust-hir-map.h"
 #include "rust-ast-resolve-base.h"
 
 namespace Rust {
@@ -35,8 +36,20 @@ public:
       bool ok = r->lookup_canonical_path (decl_node_id, &ident);
       rust_assert (ok);
 
+      Analysis::Mappings *map = Analysis::Mappings::get ();
+      HirId decl_hir_id;
+      // ScanUnused is conflicting with the dead code analysis here on types and
+      // functions. So just ignoring the warnings of item which will be handled
+      // by dead code analysis.
+      HIR::Item *found_item = nullptr;
+      if (map->lookup_node_to_hir (r->get_crate_num (), decl_node_id,
+				   &decl_hir_id))
+	{
+	  found_item = map->lookup_hir_item (r->get_crate_num (), decl_hir_id);
+	}
+
       if (!r->have_references_for_node (decl_node_id)
-	  && ident.get ().at (0) != '_')
+	  && ident.get ().at (0) != '_' && !found_item)
 	{
 	  rust_warning_at (locus, 0, "unused name '%s'", ident.get ().c_str ());
 	}
@@ -48,7 +61,8 @@ public:
   {
     auto resolver = Resolver::get ();
     resolver->iterate_name_ribs ([&] (Rib *r) -> void { ScanRib (r); });
-    resolver->iterate_type_ribs ([&] (Rib *r) -> void { ScanRib (r); });
+    // ScanUnused is conflicting with the dead code analysis here on types.
+    // resolver->iterate_type_ribs ([&] (Rib *r) -> void { ScanRib (r); });
     resolver->iterate_label_ribs ([&] (Rib *r) -> void { ScanRib (r); });
   }
 };
diff --git a/gcc/testsuite/rust/compile/torture/cfg_attr.rs b/gcc/testsuite/rust/compile/torture/cfg_attr.rs
index 1915f34..885221f 100644
--- a/gcc/testsuite/rust/compile/torture/cfg_attr.rs
+++ b/gcc/testsuite/rust/compile/torture/cfg_attr.rs
@@ -2,7 +2,7 @@ use std::env; // Add one line so gccrs doesn't believe we're parsing a shebang
 
 #[cfg_attr(feature = "somefeature", attribute = "someattr")]
 struct Feature;
-// { dg-warning "unused name" "" { target *-*-* } .-1 }
+// { dg-warning "struct is never constructed" "" { target *-*-* } .-1 }
 
 fn main() {
 }
diff --git a/gcc/testsuite/rust/compile/torture/unused1.rs b/gcc/testsuite/rust/compile/torture/unused1.rs
index 74297e0..db7eb8f 100644
--- a/gcc/testsuite/rust/compile/torture/unused1.rs
+++ b/gcc/testsuite/rust/compile/torture/unused1.rs
@@ -4,7 +4,6 @@ fn test() -> i32 {
 
 fn unused() -> i32 {
     // { dg-warning "function is never used: 'unused'" "" { target *-*-* } .-1 }
-    // { dg-warning "unused name" "" { target *-*-* } .-2 }
     2
 }
 
diff --git a/gcc/testsuite/rust/compile/torture/unused_struct.rs b/gcc/testsuite/rust/compile/torture/unused_struct.rs
new file mode 100644
index 0000000..3a20d6b
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/unused_struct.rs
@@ -0,0 +1,8 @@
+struct Foo {
+// { dg-warning "struct is never constructed" "" { target *-*-* } .-1 }
+    one: i32,
+    two: i32
+}
+
+fn main() {
+}
\ No newline at end of file