diff --git a/kexmlkem768x25519.c b/kexmlkem768x25519.c
index 18730ff8a..679446e97 100644
--- a/kexmlkem768x25519.c
+++ b/kexmlkem768x25519.c
@@ -28,7 +28,9 @@
 #include <sys/types.h>
 
 #include <stdio.h>
+#ifdef HAVE_STDINT_H
 #include <stdint.h>
+#endif
 #include <stdbool.h>
 #include <string.h>
 #include <signal.h>