diff --git a/tools/.gitignore b/tools/.gitignore
index 979f2dac0db949952ba7639a8af5db824add61d7..df3500d96530d37e9be2f0a8db774ee454f85a65 100644
--- a/tools/.gitignore
+++ b/tools/.gitignore
@@ -15,3 +15,4 @@
 /fdt_strerror.c
 /fdt_wip.c
 /libfdt_internal.h
+/zlib.h