1 files changed, 1 insertions, 1 deletions

diff --git a/src/bignum.c b/src/bignum.c
index 859896cdcf7..669df4d9ee3 100644
--- a/src/bignum.c
+++ b/src/bignum.c
@@ -465,5 +465,5 @@ int
 check_int_nonnegative (Lisp_Object x)
 {
   CHECK_INTEGER (x);
-  return Fnatnump (x) ? check_integer_range (x, 0, INT_MAX) : 0;
+  return NILP (Fnatnump (x)) ? 0 : check_integer_range (x, 0, INT_MAX);
 }