The code in question had undefined behaviour in C.

--- ash-linux-0.2/mksyntax.c.jj	Tue Aug 24 11:12:52 1993
+++ ash-linux-0.2/mksyntax.c	Wed Jun 21 08:43:03 2000
@@ -107,7 +107,7 @@ int digit_contig;	/* true if digits are 
 
 main() {
 	char c;
-	char d;
+	unsigned char d, e;
 	int sign;
 	int i;
 	char buf[80];
@@ -132,9 +132,10 @@ main() {
 		sign = 1;
 	else
 		sign = 0;
-	for (nbits = 1 ; ; nbits++) {
+	e = -1;
+	for (nbits = 1 ; nbits < 31; nbits++) {
 		d = (1 << nbits) - 1;
-		if (d == c)
+		if (d == e)
 			break;
 	}
 	printf("%s %d bit chars\n", sign? "signed" : "unsigned", nbits);