diff --git a/test/test_rewind.cxx b/test/test_rewind.cxx
index fa59b60d7..193eb905f 100644
--- a/test/test_rewind.cxx
+++ b/test/test_rewind.cxx
@@ -17,6 +17,7 @@
 #include <string>
 
 #include <string.h>
+#include <stdlib.h>
 
 class StringInputStream final : public InputStream {
 	const char *data;