diff --git a/src/bool/rpo/module.make b/src/bool/rpo/module.make
index 5c07110c9..711a348dc 100644
--- a/src/bool/rpo/module.make
+++ b/src/bool/rpo/module.make
@@ -1 +1 @@
-SRC +=    src/bool/rpo/rpo.c
\ No newline at end of file
+SRC += src/bool/rpo/rpo.c
\ No newline at end of file