PR middle-end/97840 - Bogus -Wmaybe-uninitialized passing an empty object to a function

gcc/ChangeLog:
	* tree-ssa-uninit.c (maybe_warn_operand): Call is_empty_type.
	* tree.c (default_is_empty_type): Rename...
	(is_empty_type): ...to this.
	* tree.h (is_empty_type): Declare.

diff --git a/gcc/tree-ssa-uninit.c b/gcc/tree-ssa-uninit.c
index c94831b..516a7bd 100644 (file)
--- a/gcc/tree-ssa-uninit.c
+++ b/gcc/tree-ssa-uninit.c
@@ -404,10 +404,7 @@ maybe_warn_operand (ao_ref &ref, gimple *stmt, tree lhs, tree rhs,
   tree rhstype = TREE_TYPE (rhs);
   if (POINTER_TYPE_P (rhstype))
     rhstype = TREE_TYPE (rhstype);
-  if (TYPE_EMPTY_P (rhstype)
-      || (RECORD_OR_UNION_TYPE_P (rhstype)
-         && (!first_field (rhstype)
-             || default_is_empty_record (rhstype))))
+  if (is_empty_type (rhstype))
     return NULL_TREE;
 
   bool warned = false;

diff --git a/gcc/tree.c b/gcc/tree.c
index 1ad4ad5..0fe9097 100644 (file)
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -15136,22 +15136,22 @@ get_nonnull_args (const_tree fntype)
 /* Returns true if TYPE is a type where it and all of its subobjects
    (recursively) are of structure, union, or array type.  */
 
-static bool
-default_is_empty_type (tree type)
+bool
+is_empty_type (const_tree type)
 {
   if (RECORD_OR_UNION_TYPE_P (type))
     {
       for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
        if (TREE_CODE (field) == FIELD_DECL
            && !DECL_PADDING_P (field)
-           && !default_is_empty_type (TREE_TYPE (field)))
+           && !is_empty_type (TREE_TYPE (field)))
          return false;
       return true;
     }
   else if (TREE_CODE (type) == ARRAY_TYPE)
     return (integer_minus_onep (array_type_nelts (type))
            || TYPE_DOMAIN (type) == NULL_TREE
-           || default_is_empty_type (TREE_TYPE (type)));
+           || is_empty_type (TREE_TYPE (type)));
   return false;
 }
 
@@ -15170,7 +15170,7 @@ default_is_empty_record (const_tree type)
   if (TREE_ADDRESSABLE (type))
     return false;
 
-  return default_is_empty_type (TYPE_MAIN_VARIANT (type));
+  return is_empty_type (TYPE_MAIN_VARIANT (type));
 }
 
 /* Determine whether TYPE is a structure with a flexible array member,

diff --git a/gcc/tree.h b/gcc/tree.h
index 9a713cd..5c0e3cc 100644 (file)
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -6233,6 +6233,7 @@ extern void gt_pch_nx (tree &);
 extern void gt_pch_nx (tree &, gt_pointer_operator, void *);
 
 extern bool nonnull_arg_p (const_tree);
+extern bool is_empty_type (const_tree);
 extern bool default_is_empty_record (const_tree);
 extern bool flexible_array_type_p (const_tree);
 extern HOST_WIDE_INT arg_int_size_in_bytes (const_tree);