When executing ./configure for Gnatstudio I receive the following error. I have searched for references related to this but can't anything associated with it. Gprconfig has been configured without incident.

checking that your gnat compiler works with a simple example... GNAT-TEMP-000001.TMP:108:11: undefined attribute "bindfile_option_substitution" GNAT-TEMP-000001.TMP:109:11: undefined attribute "bindfile_option_substitution" gprbuild: processing of configuration project "/tmp/GNAT-TEMP-000001.TMP" failed

Locating variable "bindfile_option_substitution." Don't know where this is located.

I have a TREE_MODEL in GTK. One of the columns is a GTK.CELL_RENDERER_TOGGLE to determine which rows are selected. I've tried to configure a Callback to activate/desactivate each toggle independiently but i have only achieved a callback that activate/desactivate the whole column. Is it possible?

package Q_SUBMIT_CHECKBOX_CALLBACK is new
   GTK.HANDLERS.USER_CALLBACK
   (WIDGET_TYPE => GTK.CELL_RENDERER_TOGGLE.GTK_CELL_RENDERER_TOGGLE_RECORD,
   USER_TYPE   => INTEGER);

GTK.TREE_VIEW_COLUMN.GTK_NEW (TREE_COLUMN => V_TREE_VIEW_COLUMN);

V_NUM :=
       GTK.TREE_VIEW.APPEND_COLUMN
           (TREE_VIEW => V_TREE,
            COLUMN    => V_TREE_VIEW_COLUMN);

GTK.CELL_RENDERER_TOGGLE.GTK_NEW (SELF => V_TOGGLE_RENDER);

GLIB.PROPERTIES.SET_PROPERTY
       (OBJECT => V_TOGGLE_RENDER,
        NAME   => GTK.CELL_RENDERER_TOGGLE.ACTIVATABLE_PROPERTY,
        VALUE  => TRUE);

GTK.TREE_VIEW_COLUMN.PACK_START
        (CELL_LAYOUT => V_TREE_VIEW_COLUMN,
         CELL        => V_TOGGLE_RENDER,
         EXPAND      => V_EXPAND);

Q_SUBMIT_CHECKBOX_CALLBACK.CONNECT
       (WIDGET    => V_TOGGLE_RENDER,
        NAME      => "toogled",
        MARSH     => Q_SUBMIT_CHECKBOX_CALLBACK.TO_MARSHALLER
           (P_CHECKBOX_CALLBACK'ACCESS),
        USER_DATA => 0);

People are having much trouble with GtkAda on Big Sur, so I thought "why not try building Gtk?" - as here.

Unfortunately, it's just too complicated & runs into so many problems that I give up.