diff --git a/m4/.gitignore b/m4/.gitignore
index 9edab25..776db74 100644
--- a/m4/.gitignore
+++ b/m4/.gitignore
@@ -54,6 +54,7 @@
 /stdio_h.m4
 /stdlib_h.m4
 /string_h.m4
+/sys_cdefs_h.m4
 /sys_socket_h.m4
 /sys_stat_h.m4
 /sys_time_h.m4