diff --git a/.gitignore b/.gitignore
index 7c2fe53..787a967 100644
--- a/.gitignore
+++ b/.gitignore
@@ -20,7 +20,8 @@ install-sh
 libbsdiff.la
 libtool
 ltmain.sh
-m4/
+m4/*
+!m4/.gitignore
 missing
 src/.dirstamp
 src/*.gcda
diff --git a/m4/.gitignore b/m4/.gitignore
new file mode 100644
index 0000000..e69de29