Add a new error for situations when a switch expression doesn't have a default case

Author: Daniel-Cortez

source/compiler/sc3.c

@@ -1807,6 +1807,7 @@ static int hier2(value *lval)
     setlabel(lbl_table);
     assert(swdefault==FALSE || swdefault==TRUE);
     if (swdefault==FALSE) {
+      error(95);    /* switch expression must contain a "default" case */
       /* store lbl_exit as the "none-matched" label in the switch table */
       strcpy(labelname,itoh(lbl_exit));
     } else {

source/compiler/sc5.c

@@ -133,7 +133,8 @@ static char *errmsg[] = {
 /*091*/  "ambiguous constant; tag override is required (symbol \"%s\")\n",
 /*092*/  "functions may not return arrays of unknown size (symbol \"%s\")\n",
 /*093*/  "\"__addressof\" operator is invalid in preprocessor expressions\n",
-/*094*/  "division by zero\n"
+/*094*/  "division by zero\n",
+/*095*/  "switch expression must contain a \"default\" case\n"
 };
 
 static char *fatalmsg[] = {