Index: src/Parser/parser.yy
===================================================================
--- src/Parser/parser.yy	(revision 2d0f918fccda13d7214a5f8726ab517b71632108)
+++ src/Parser/parser.yy	(revision 3982384b9c4ea1f8724897508e84041d2ab66cf1)
@@ -2687,8 +2687,4 @@
 			$$ = DeclarationNode::newEnum( nullptr, $7, true, true, $3 )->addQualifiers( $5 );
 		}
-	| ENUM '(' ')' attribute_list_opt '{' enumerator_list comma_opt '}'
-		{
-			$$ = DeclarationNode::newEnum( nullptr, $6, true, true )->addQualifiers( $4 );
-		}
 	| ENUM '(' cfa_abstract_parameter_declaration ')' attribute_list_opt identifier attribute_list_opt
 		{
@@ -2700,18 +2696,8 @@
 			$$ = DeclarationNode::newEnum( $6, $11, true, true, $3, $9 )->addQualifiers( $5 )->addQualifiers( $7 );
 		}
-	| ENUM '(' ')' attribute_list_opt identifier attribute_list_opt
-	  hide_opt '{' enumerator_list comma_opt '}'
-		{
-			$$ = DeclarationNode::newEnum( $5, $9, true, true, nullptr, $7 )->addQualifiers( $4 )->addQualifiers( $6 );
-		}
 	| ENUM '(' cfa_abstract_parameter_declaration ')' attribute_list_opt typedef_name attribute_list_opt
 	  hide_opt '{' enumerator_list comma_opt '}'
 		{
 			$$ = DeclarationNode::newEnum( $6->name, $10, true, true, $3, $8 )->addQualifiers( $5 )->addQualifiers( $7 );
-		}
-	| ENUM '(' ')' attribute_list_opt typedef_name attribute_list_opt
-	  hide_opt '{' enumerator_list comma_opt '}'
-		{
-			$$ = DeclarationNode::newEnum( $5->name, $9, true, true, nullptr, $7 )->addQualifiers( $4 )->addQualifiers( $6 );
 		}
 	| enum_type_nobody
@@ -2826,5 +2812,7 @@
 
 cfa_abstract_parameter_declaration:						// CFA, new & old style parameter declaration
-	abstract_parameter_declaration
+	// empty
+		{ $$ = nullptr; }
+	| abstract_parameter_declaration
 	| cfa_identifier_parameter_declarator_no_tuple
 	| cfa_abstract_tuple