diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index f395488971..0ad533c045 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -1342,7 +1342,7 @@ static void write_pack_file(void)
 
 			if (write_bitmap_index) {
 				bitmap_writer_init(&bitmap_writer,
-						   the_repository);
+						   the_repository, &to_pack);
 				bitmap_writer_set_checksum(&bitmap_writer, hash);
 				bitmap_writer_build_type_index(&bitmap_writer,
 					&to_pack, written_list, nr_written);
diff --git a/midx-write.c b/midx-write.c
index a77ee73c68..62f507eb72 100644
--- a/midx-write.c
+++ b/midx-write.c
@@ -825,7 +825,7 @@ static int write_midx_bitmap(const char *midx_name,
 	for (i = 0; i < pdata->nr_objects; i++)
 		index[i] = &pdata->objects[i].idx;
 
-	bitmap_writer_init(&writer, the_repository);
+	bitmap_writer_init(&writer, the_repository, pdata);
 	bitmap_writer_show_progress(&writer, flags & MIDX_PROGRESS);
 	bitmap_writer_build_type_index(&writer, pdata, index,
 				       pdata->nr_objects);
diff --git a/pack-bitmap-write.c b/pack-bitmap-write.c
index bf96c80898..4a7d2d1370 100644
--- a/pack-bitmap-write.c
+++ b/pack-bitmap-write.c
@@ -41,13 +41,15 @@ static inline int bitmap_writer_nr_selected_commits(struct bitmap_writer *writer
 	return writer->selected_nr - writer->pseudo_merges_nr;
 }
 
-void bitmap_writer_init(struct bitmap_writer *writer, struct repository *r)
+void bitmap_writer_init(struct bitmap_writer *writer, struct repository *r,
+			struct packing_data *pdata)
 {
 	memset(writer, 0, sizeof(struct bitmap_writer));
 	if (writer->bitmaps)
 		BUG("bitmap writer already initialized");
 	writer->bitmaps = kh_init_oid_map();
 	writer->pseudo_merge_commits = kh_init_oid_map();
+	writer->to_pack = pdata;
 
 	string_list_init_dup(&writer->pseudo_merge_groups);
 
diff --git a/pack-bitmap.h b/pack-bitmap.h
index 1171e6d989..ab20d6a0b6 100644
--- a/pack-bitmap.h
+++ b/pack-bitmap.h
@@ -123,7 +123,8 @@ struct bitmap_writer {
 	unsigned char pack_checksum[GIT_MAX_RAWSZ];
 };
 
-void bitmap_writer_init(struct bitmap_writer *writer, struct repository *r);
+void bitmap_writer_init(struct bitmap_writer *writer, struct repository *r,
+			struct packing_data *pdata);
 void bitmap_writer_show_progress(struct bitmap_writer *writer, int show);
 void bitmap_writer_set_checksum(struct bitmap_writer *writer,
 				const unsigned char *sha1);