(merge_attributes): New function.

(merge_attributes): New function.  Move code from
common_type to here.
(common_type): Call merge_attributes instead of having inline code.

From-SVN: r10620

gcc/c-typeck.c

@@ -166,6 +166,43 @@ qualify_type (type, like)
   return c_build_type_variant (type, constflag, volflag);
 }
 
+/* Return an attribute list that is the union of a1 and a2.  */
+tree
+merge_attributes (a1, a2)
+     register tree a1, a2;
+{
+  tree attributes;
+
+  /* Either one unset?  Take the set one.  */
+
+  if (! (attributes = a1))
+    attributes = a2;
+
+  /* One that completely contains the other?  Take it.  */
+
+  else if (a2 && ! attribute_list_contained (a1, a2))
+    if (attribute_list_contained (a2, a1))
+      attributes = a2;
+    else
+      {
+	/* Pick the longest list, and hang on the other list.  */
+	/* ??? For the moment we punt on the issue of attrs with args.  */
+
+	if (list_length (a1) < list_length (a2))
+	  attributes = a2, a2 = a1;
+
+	for (; a2; a2 = TREE_CHAIN (a2))
+	  if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
+				attributes) == NULL_TREE)
+	    {
+	      a1 = copy_node (a2);
+	      TREE_CHAIN (a1) = attributes;
+	      attributes = a1;
+	    }
+      }
+  return attributes;
+}
+
 /* Return the common type of two types.
    We assume that comptypes has already been done and returned 1;
    if that isn't so, this may crash.  In particular, we assume that qualifiers
@@ -193,39 +230,7 @@ common_type (t1, t2)
     return t1;
 
   /* Merge the attributes */
-
-  { register tree a1, a2;
-    a1 = TYPE_ATTRIBUTES (t1);
-    a2 = TYPE_ATTRIBUTES (t2);
-
-    /* Either one unset?  Take the set one.  */
-
-    if (!(attributes = a1))
-       attributes = a2;
-
-    /* One that completely contains the other?  Take it.  */
-
-    else if (a2 && !attribute_list_contained (a1, a2))
-       if (attribute_list_contained (a2, a1))
-	  attributes = a2;
-       else
-	{
-	  /* Pick the longest list, and hang on the other list.  */
-	  /* ??? For the moment we punt on the issue of attrs with args.  */
-	
-	  if (list_length (a1) < list_length (a2))
-	     attributes = a2, a2 = a1;
-
-	  for (; a2; a2 = TREE_CHAIN (a2))
-	    if (lookup_attribute (IDENTIFIER_POINTER (TREE_PURPOSE (a2)),
-				  attributes) == NULL_TREE)
-	      {
-		a1 = copy_node (a2);
-		TREE_CHAIN (a1) = attributes;
-		attributes = a1;
-	      }
-	}
-  }
+  attributes = merge_attributes (TYPE_ATTRIBUTES (t1), TYPE_ATTRIBUTES (t2));
 
   /* Treat an enum type as the unsigned integer type of the same width.  */