add_buffer_overlay  680 src/buffer.c         add_buffer_overlay (to, XOVERLAY (copy), node->begin, node->end);
add_buffer_overlay 3589 src/buffer.c     add_buffer_overlay (b, XOVERLAY (ov), obeg, oend);
add_buffer_overlay 3672 src/buffer.c         add_buffer_overlay (XBUFFER (buffer), XOVERLAY (overlay), n_beg, n_end);