diff --git a/programs/x509/cert_app.c b/programs/x509/cert_app.c
index 2c8a88d..d7cacdb 100644
--- a/programs/x509/cert_app.c
+++ b/programs/x509/cert_app.c
@@ -67,7 +67,7 @@
     int permissive;             /* permissive parsing                   */
 } opt;
 
-void my_debug( void *ctx, int level, const char *str )
+static void my_debug( void *ctx, int level, const char *str )
 {
     if( level < opt.debug_level )
     {
@@ -76,7 +76,7 @@
     }
 }
 
-int my_verify( void *data, x509_cert *crt, int depth, int *flags )
+static int my_verify( void *data, x509_cert *crt, int depth, int *flags )
 {
     char buf[1024];
     ((void) data);