diff --git a/src/asm/yaccprt3.y b/src/asm/yaccprt3.y
index b531e1a0..aa9f736f 100644
--- a/src/asm/yaccprt3.y
+++ b/src/asm/yaccprt3.y
@@ -47,6 +47,7 @@ macro			:	T_ID
 
 						if( !fstk_RunMacro($1) )
 						{
+							fprintf(stderr, "Macro '%s' not defined", $1);
 							yyerror( "No such macro" );
 						}
 					}