diff --git a/builtin/commit.c b/builtin/commit.c
index 877955e..829daac 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -31,6 +31,7 @@
 #include "object-name.h"
 #include "parse-options.h"
 #include "preload-index.h"
+#include "read-cache.h"
 #include "string-list.h"
 #include "rerere.h"
 #include "unpack-trees.h"