int i, num_paths, needsep, show_log_first, num_parent = parents->nr;
 
        diffopts = *opt;
+       diff_tree_setup_paths(diffopts.pathspec.raw, &diffopts);
        diffopts.output_format = DIFF_FORMAT_NO_OUTPUT;
        DIFF_OPT_SET(&diffopts, RECURSIVE);
        DIFF_OPT_CLR(&diffopts, ALLOW_EXTERNAL);
                paths = paths->next;
                free(tmp);
        }
+
+       diff_tree_release_paths(&diffopts);
 }
 
 void diff_tree_combined_merge(const struct commit *commit, int dense,