diff --git a/components/storage/blockdevice/COMPONENT_SD/TESTS/filesystem/fopen/fopen.cpp b/components/storage/blockdevice/COMPONENT_SD/TESTS/filesystem/fopen/fopen.cpp
index 5c18d2c5fa..f0bcea0e0d 100644
--- a/components/storage/blockdevice/COMPONENT_SD/TESTS/filesystem/fopen/fopen.cpp
+++ b/components/storage/blockdevice/COMPONENT_SD/TESTS/filesystem/fopen/fopen.cpp
@@ -928,7 +928,7 @@ control_t fsfat_fopen_test_08(const size_t call_count)
     fclose(fp);
     return CaseNext;
 }
-#endif
+#endif // !defined(__MICROLIB)
 
 /** @brief  test for operation of ftell()
  *