diff --git a/.hgignore b/.hgignore
index a7bb07c5..d5895afe 100644
--- a/.hgignore
+++ b/.hgignore
@@ -21,6 +21,7 @@ lib/libgnu.a
 lib/unistd.h
 lib/stdbool.h
 lib/stdint.h
+lib/stdio.h
 lib/stdlib.h
 lib/string.h
 lib/wchar.h