diff --git a/examples/simple_decoder.c b/examples/simple_decoder.c
index 08a2166..8ccc810 100644
--- a/examples/simple_decoder.c
+++ b/examples/simple_decoder.c
@@ -88,7 +88,7 @@
 
 static const char *exec_name;
 
-void usage_exit() {
+void usage_exit(void) {
   fprintf(stderr, "Usage: %s <infile> <outfile>\n", exec_name);
   exit(EXIT_FAILURE);
 }