diff --git a/third_party/giflib/lib/gif_hash.c b/third_party/giflib/lib/gif_hash.c
index 157569c3f..11bdd21e8 100644
--- a/third_party/giflib/lib/gif_hash.c
+++ b/third_party/giflib/lib/gif_hash.c
@@ -48,6 +48,7 @@
 #endif /* HAVE_FCNTL_H */
 #include <stdio.h>
 #include <string.h>
+#include <stdlib.h>
 #include "gif_lib.h"
 #include "gif_hash.h"
 #include "gif_lib_private.h"