diff --git a/ext/f2c_libs/lbitbits.c b/ext/f2c_libs/lbitbits.c
index 5b6ccf72d..2f44abf9d 100644
--- a/ext/f2c_libs/lbitbits.c
+++ b/ext/f2c_libs/lbitbits.c
@@ -44,11 +44,11 @@ lbit_cshift(integer a, integer b, integer len)
  full_len:
 		if (b >= 0) {
 			b %= LONGBITS;
-			return (integer)(x << b | x >> LONGBITS -b );
+			return (integer)(x << b | x >> (LONGBITS -b) );
 			}
 		b = -b;
 		b %= LONGBITS;
-		return (integer)(x << LONGBITS - b | x >> b);
+		return (integer)(x << (LONGBITS - b) | x >> b);
 		}
 	y = z = (unsigned long)-1;
 	y <<= len;
@@ -57,11 +57,11 @@ lbit_cshift(integer a, integer b, integer len)
 	x &= z;
 	if (b >= 0) {
 		b %= len;
-		return (integer)(y | z & (x << b | x >> len - b));
+		return (integer)((y) | (z & (x << b | x >> (len - b))));
 		}
 	b = -b;
 	b %= len;
-	return (integer)(y | z & (x >> b | x << len - b));
+	return (integer)((y) | (z & (x >> b | x << (len - b))));
 	}
 #ifdef __cplusplus
 }