diff --git a/client/cmdhfmfhard.c b/client/cmdhfmfhard.c
index f7c2f650d..95a6f8d7f 100644
--- a/client/cmdhfmfhard.c
+++ b/client/cmdhfmfhard.c
@@ -1304,7 +1304,7 @@ static void generate_candidates(uint16_t sum_a0, uint16_t sum_a8)
 			}
 		}
 	}
-	printf("Number of possible keys with Sum(a0) = %d: %lld (2^%1.1f)\n", sum_a0, maximum_states, log(maximum_states)/log(2.0));
+	printf("Number of possible keys with Sum(a0) = %d: %"PRIu64" (2^%1.1f)\n", sum_a0, maximum_states, log(maximum_states)/log(2.0));
 	
 	init_statelist_cache();
 	
@@ -1353,7 +1353,7 @@ static void generate_candidates(uint16_t sum_a0, uint16_t sum_a8)
 	for (statelist_t *sl = candidates; sl != NULL; sl = sl->next) {
 		maximum_states += (uint64_t)sl->len[ODD_STATE] * sl->len[EVEN_STATE];
 	}
-	printf("Number of remaining possible keys: %lld (2^%1.1f)\n", maximum_states, log(maximum_states)/log(2.0));
+	printf("Number of remaining possible keys: %"PRIu64" (2^%1.1f)\n", maximum_states, log(maximum_states)/log(2.0));
 	if (write_stats) {
 		if (maximum_states != 0) {
 			fprintf(fstats, "%1.1f;", log(maximum_states)/log(2.0));