Hi,
in fact , the problem was the $oeuvre variable, for it is an array
i had to write :
$term_taxonomy_ids = wp_set_object_terms( $oeuvre->ID, $term_id, ‘statut_oeuvre’);
in steadof
$term_taxonomy_ids = wp_set_object_terms( $oeuvre, $term_id, ‘statut_oeuvre’);
Thanks for help
Fred