diff --git a/src/config/help.c b/src/config/help.c
index 2f0607d..181edbd 100644
--- a/src/config/help.c
+++ b/src/config/help.c
@@ -455,6 +455,7 @@ static void Usage (vlc_object_t *p_this, char const *psz_search)
                     psz_buffer[0] = '\0';
                     for( i = 0; i < p_item->list_count; i++ )
                     {
+                        if( p_item->list.psz[i] == NULL ) break;
                         if( i ) strcat( psz_buffer, "," );
                         strcat( psz_buffer, p_item->list.psz[i] );
                     }
@@ -483,6 +484,7 @@ static void Usage (vlc_object_t *p_this, char const *psz_search)
                     psz_buffer[0] = '\0';
                     for( i = 0; i < p_item->list_count; i++ )
                     {
+                        if( p_item->list_text[i] == NULL ) break;
                         if( i ) strcat( psz_buffer, ", " );
                         sprintf( psz_buffer + strlen(psz_buffer), "%i (%s)",
                                  p_item->list.i[i],