diff --git a/string_list.c b/string_list.c
index 72128434c8..646b0b3b1a 100644
--- a/string_list.c
+++ b/string_list.c
@@ -21,6 +21,7 @@
 #include "miscellaneous.h"
 #include "compat/strl.h"
 #include "string_list.h"
+#include "compat/posix_string.h"
 
 void string_list_free(struct string_list *list)
 {