diff --git a/include/git2/sys/filter.h b/include/git2/sys/filter.h
index d0e5d4d..8c6d7a5 100644
--- a/include/git2/sys/filter.h
+++ b/include/git2/sys/filter.h
@@ -271,7 +271,7 @@
 };
 
 #define GIT_FILTER_VERSION 1
-
+#define GIT_FILTER_INIT {GIT_FILTER_VERSION}
 /**
  * Register a filter under a given name with a given priority.
  *