--- numbers.c.~1.181.~	2003-05-04 09:09:49.000000000 +1000
+++ numbers.c	2003-05-04 09:34:56.000000000 +1000
@@ -1387,7 +1387,7 @@
         {
           mpz_t z_n;
           mpz_init (z_n);
-          mpz_neg (z_n, SCM_I_BIG_MPZ (n));
+          mpz_com (z_n, SCM_I_BIG_MPZ (n));
           scm_remember_upto_here_1 (n);
           count = mpz_popcount (z_n);
           mpz_clear (z_n);