Index: src/Concurrency/Keywords.cpp
===================================================================
--- src/Concurrency/Keywords.cpp	(revision 5f225f59101d268668c9c4862e607c9573860bfb)
+++ src/Concurrency/Keywords.cpp	(revision db19e1d0d4adcc296ca7022c295f441155d4b6dc)
@@ -1510,5 +1510,5 @@
 
 ast::ptr<ast::Type> MutexKeyword::generic_func =
-	new ast::FunctionType( ast::VariableArgs );
+	new ast::FunctionType( ast::FixedArgs );
 
 // --------------------------------------------------------------------------
Index: src/Concurrency/Waitfor.cpp
===================================================================
--- src/Concurrency/Waitfor.cpp	(revision 5f225f59101d268668c9c4862e607c9573860bfb)
+++ src/Concurrency/Waitfor.cpp	(revision db19e1d0d4adcc296ca7022c295f441155d4b6dc)
@@ -302,5 +302,5 @@
 	const ast::ObjectDecl * monitors = declMonitors( out, clause );
 	ast::Type * fptr_t = new ast::PointerType(
-			new ast::FunctionType( ast::VariableArgs ) );
+			new ast::FunctionType( ast::FixedArgs ) );
 
 	const ast::VariableExpr * variableExpr =