Index: src/Parser/parser.yy
===================================================================
--- src/Parser/parser.yy	(revision d61d0347a13b953ca48c9a9bbd1d4e9c0906c5ed)
+++ src/Parser/parser.yy	(revision 997185e1a79d8e46351af7db167616c955086e6e)
@@ -2569,8 +2569,4 @@
 			$$ = DeclarationNode::newEnum( nullptr, $7, true, true, $3 )->addQualifiers( $5 );
 		}
-	| ENUM '(' ')' attribute_list_opt '{' enumerator_list comma_opt '}'
-		{
-			$$ = DeclarationNode::newEnum( nullptr, $6, true, true )->addQualifiers( $4 );
-		}
 	| ENUM '(' cfa_abstract_parameter_declaration ')' attribute_list_opt identifier attribute_list_opt
 		{
@@ -2582,18 +2578,8 @@
 			$$ = DeclarationNode::newEnum( $6, $11, true, true, $3, $9 )->addQualifiers( $5 )->addQualifiers( $7 );
 		}
-	| ENUM '(' ')' attribute_list_opt identifier attribute_list_opt
-	  hide_opt '{' enumerator_list comma_opt '}'
-		{
-			$$ = 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
@@ -2708,5 +2694,7 @@
 
 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