diff --git a/fastafile.c b/fastafile.c
index 6c14b99..c9918dc 100644
--- a/fastafile.c
+++ b/fastafile.c
@@ -1,6 +1,7 @@
+#include <stdlib.h>
+#include <string.h>
 #include <stdio.h>
 #include <ctype.h>
-#include <malloc.h>
 
 #include "fastafile.h"
 
diff --git a/mdust.c b/mdust.c
index f2bae99..8249341 100644
--- a/mdust.c
+++ b/mdust.c
@@ -1,3 +1,4 @@
+#include <string.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <ctype.h>
