diff --git a/sha1_file.c b/sha1_file.c
index 4acbf8e..bf6c8da 100644
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -35,12 +35,21 @@
 /* The maximum size for an object header. */
 #define MAX_HEADER_LEN 32
 
+
+#define EMPTY_TREE_SHA1_BIN_LITERAL \
+	 "\x4b\x82\x5d\xc6\x42\xcb\x6e\xb9\xa0\x60" \
+	 "\xe5\x4b\xf8\xd6\x92\x88\xfb\xee\x49\x04"
+
+#define EMPTY_BLOB_SHA1_BIN_LITERAL \
+	"\xe6\x9d\xe2\x9b\xb2\xd1\xd6\x43\x4b\x8b" \
+	"\x29\xae\x77\x5a\xd8\xc2\xe4\x8c\x53\x91"
+
 const unsigned char null_sha1[GIT_MAX_RAWSZ];
 const struct object_id null_oid;
-const struct object_id empty_tree_oid = {
+static const struct object_id empty_tree_oid = {
 	EMPTY_TREE_SHA1_BIN_LITERAL
 };
-const struct object_id empty_blob_oid = {
+static const struct object_id empty_blob_oid = {
 	EMPTY_BLOB_SHA1_BIN_LITERAL
 };