fix build if TinyUSB not present (#631)
diff --git a/test/kitchen_sink/CMakeLists.txt b/test/kitchen_sink/CMakeLists.txt
index 52067b8..024d42c 100644
--- a/test/kitchen_sink/CMakeLists.txt
+++ b/test/kitchen_sink/CMakeLists.txt
@@ -97,7 +97,12 @@
pico_add_extra_outputs(kitchen_sink)
add_executable(kitchen_sink_extra_stdio)
-suppress_tinyusb_warnings() # suppress warnings explicitly in TinyUSB files which have them
+if (COMMAND suppress_tinyusb_warnings)
+ # Explicitly suppress warnings in TinyUSB files which have them (this has to be done
+ # from the project that uses them per CMake "feature"). Note the function comes from
+ # TinyUSB itself, so we have to guard against TinyUSB not being present with the above if
+ suppress_tinyusb_warnings()
+endif()
target_link_libraries(kitchen_sink_extra_stdio kitchen_sink_libs kitchen_sink_options)
pico_add_extra_outputs(kitchen_sink_extra_stdio)
pico_enable_stdio_usb(kitchen_sink_extra_stdio 1)
