handle intorcard_type better in case statements

lang/m2/comp/chk_expr.c

@@ -832,13 +832,11 @@ ChkBinOper(expp)
 	tpl = BaseType(expp->nd_left->nd_type);
 	tpr = BaseType(expp->nd_right->nd_type);
 
-	if (tpl == intorcard_type) {
-		if (tpr == int_type || tpr == card_type) {
+	if (intorcard(tpl, tpr) != 0) {
+		if (tpl == intorcard_type) {
 			 expp->nd_left->nd_type = tpl = tpr;
 		}
-	}
-	if (tpr == intorcard_type) {
-		if (tpl == int_type || tpl == card_type) {
+		if (tpr == intorcard_type) {
 			expp->nd_right->nd_type = tpr = tpl;
 		}
 	}

lang/m2/comp/declar.g

@@ -400,7 +400,11 @@ CaseLabels(t_type **ptp; register t_node **pnd;)
 }:
 	ConstExpression(pnd)
 			{ 
-			  if (*ptp != 0 && ChkCompat(pnd, *ptp, "case label")) {
+			  if (*ptp != 0) {
+				t_type *tp = intorcard(*ptp,
+					BaseType((*pnd)->nd_type), 0);
+				if (tp) *ptp = tp;
+				ChkCompat(pnd, *ptp, "case label");
 			  }
 			  nd = *pnd;
 			  nd->nd_type = BaseType(nd->nd_type);	/* ??? */

lang/m2/comp/type.H

@@ -187,6 +187,7 @@ extern t_type
 	*proc_type(),
 	*enum_type(),
 	*qualified_type(),
+	*intorcard(),
 	*RemoveEqual();	/* All from type.c */
 
 #define NULLTYPE ((t_type *) 0)

lang/m2/comp/type.c

@@ -795,6 +795,23 @@ lcm(m, n)
 	return m * (n / gcd(m, n));
 }
 
+t_type *
+intorcard(left, right)
+	register t_type *left, *right;
+{
+	if (left == intorcard_type) {
+		if (right == int_type || right == card_type) {
+			return right;
+		}
+	}
+	else if (right == intorcard_type) {
+		if (left == int_type || left == card_type) {
+			return left;
+		}
+	}
+	return 0;
+}
+
 #ifdef DEBUG
 DumpType(tp)
 	register t_type *tp;