diff --git a/doc/doxygen/Makefile b/doc/doxygen/Makefile
index 2363ff6d8e4fccff85f86536d7c07985c3fa3119..9dad5f493276c951060770b23ab9fc14552451b6 100644
--- a/doc/doxygen/Makefile
+++ b/doc/doxygen/Makefile
@@ -2,4 +2,4 @@ doc:
 	doxygen riot.doxyfile
 
 clean:
-	@rm -rf latex man html
+	-@rm -rf latex man html