diff --git a/samples/main.cc b/samples/main.cc
index 900cb03..c7c9999 100644
--- a/samples/main.cc
+++ b/samples/main.cc
@@ -912,6 +912,8 @@
 
   return true;
 #else
+  (void)program;
+  (void)options;
   std::cerr << "GLSL writer not enabled in tint build" << std::endl;
   return false;
 #endif  // TINT_BUILD_GLSL_WRITER