diff --git a/decode.cc b/decode.cc
index ba967ae..18e19cf 100644
--- a/decode.cc
+++ b/decode.cc
@@ -60,4 +60,6 @@ int main(int argc, char** argv) {
     printf("Failed to write png.\n");
     return 1;
   }
+
+  return 0;
 }