diff --git a/programs/pkey/gen_key.c b/programs/pkey/gen_key.c
index 194a5cb..4ad1629 100644
--- a/programs/pkey/gen_key.c
+++ b/programs/pkey/gen_key.c
@@ -39,7 +39,7 @@
 
 #define DEV_RANDOM_THRESHOLD        32
 
-int dev_random_entropy_poll(void *data, unsigned char *output,
+static int dev_random_entropy_poll(void *data, unsigned char *output,
                             size_t len, size_t *olen)
 {
     FILE *file;