diff --git a/tests/.gitignore b/tests/.gitignore
index 8f7315d..07ac5d6 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -11,6 +11,7 @@
 include/test/instrument_record_status.h
 
 src/*.o
+src/test_helpers/*.o
 src/drivers/*.o
 src/libmbed*