diff --git a/src/cc65/datatype.c b/src/cc65/datatype.c
index 5baf53269..0d3edba74 100644
--- a/src/cc65/datatype.c
+++ b/src/cc65/datatype.c
@@ -6,10 +6,10 @@
 /*                                                                           */
 /*                                                                           */
 /*                                                                           */
-/* (C) 1998     Ullrich von Bassewitz                                        */
-/*              Wacholderweg 14                                              */
-/*              D-70597 Stuttgart                                            */
-/* EMail:       uz@musoftware.de                                             */
+/* (C) 1998-2000 Ullrich von Bassewitz                                       */
+/*               Wacholderweg 14                                             */
+/*               D-70597 Stuttgart                                           */
+/* EMail:        uz@musoftware.de                                            */
 /*                                                                           */
 /*                                                                           */
 /* This software is provided 'as-is', without any expressed or implied       */
@@ -342,6 +342,7 @@ unsigned SizeOf (const type* tarray)
     switch (*tarray) {
 
 	case T_VOID:
+	    Error (ERR_ILLEGAL_SIZE);
 	    return 0;
 
 	case T_CHAR: