diff --git a/builtin/pull.c b/builtin/pull.c
index 3ecb881b0b..a9f7553f30 100644
--- a/builtin/pull.c
+++ b/builtin/pull.c
@@ -335,16 +335,16 @@ static void get_merge_heads(struct sha1_array *merge_heads)
 	const char *filename = git_path("FETCH_HEAD");
 	FILE *fp;
 	struct strbuf sb = STRBUF_INIT;
-	unsigned char sha1[GIT_SHA1_RAWSZ];
+	struct object_id oid;
 
 	if (!(fp = fopen(filename, "r")))
 		die_errno(_("could not open '%s' for reading"), filename);
 	while (strbuf_getline_lf(&sb, fp) != EOF) {
-		if (get_sha1_hex(sb.buf, sha1))
+		if (get_oid_hex(sb.buf, &oid))
 			continue;  /* invalid line: does not start with SHA1 */
 		if (starts_with(sb.buf + GIT_SHA1_HEXSZ, "\tnot-for-merge\t"))
 			continue;  /* ref is not-for-merge */
-		sha1_array_append(merge_heads, sha1);
+		sha1_array_append(merge_heads, oid.hash);
 	}
 	fclose(fp);
 	strbuf_release(&sb);