diff --git a/makefiles b/makefiles
index b91c20d..6605d1b 160000
--- a/makefiles
+++ b/makefiles
@@ -1 +1 @@
-Subproject commit b91c20df9f759ec5962f96814a63ca936bdbae79
+Subproject commit 6605d1be88e7a73bf8f8954c486d6a411842866a
diff --git a/overview/Makefile b/overview/Makefile
index a32e9ff..e1d33c4 100644
--- a/overview/Makefile
+++ b/overview/Makefile
@@ -7,5 +7,10 @@ SRC+= 		contents.tex
 slides.pdf: ${SRC}
 
 
+.PHONY: clean
+clean:
+	${RM} slides.pdf
+
+
 INCLUDE_MAKEFILES=../makefiles
 include ${INCLUDE_MAKEFILES}/tex.mk