diff --git a/tests/Makefile b/tests/Makefile
index b62efab8..eb4c4e05 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -100,5 +100,5 @@ scan-build:
 	scan-build -o ./mlib-report make check XCFLAGS="-std=c99"
 
 sanitize:
-	make check XCFLAGS="-fsanitize=address,undefined"
-	make check XCFLAGS="-fsanitize=thread -pie -fPIE"
+	make clean check XCFLAGS="-fsanitize=address,undefined"
+	make clean check XCFLAGS="-fsanitize=thread -pie -fPIE"