Re: Strange behavior of my program

[onetmt <onetmt gmail com>]

Il 01/12/2013 21:01, Alberto Zichittella ha scritto:
> This message dialog causes a strange behavior on my program. It seems
> that the call to gtk_message_dialog_new() change the value of the const
> gchar* pointer, last parameter. 
>
> Furthermore, the value of the const gchar* variable "message" change
> from "Il risultato e' -number-" to "Il risult(", I don't know why. 
> I know that the call changes the value (and the address) of message
> because I use gdb.
>
> I develope on ubuntu gnome 13.10 using Code::Blocks , on a 64bit system,
> with gtk+-3.0
>
>
>     const gchar* message;
>     /*the function risolviFormat() create a gchar* pointer, using malloc
> to allocate memory */
>     message = espressione->risolviFormat();   //message is, for example,

Try this substitution:

    gchar *message;

    message = g_strdup_printf("Il risultato e': %f", result);
    dialog = gtk_message_dialog_new(NULL,
                                    GTK_DIALOG_DESTROY_WITH_PARENT,
                                    GTK_MESSAGE_INFO,
                                    GTK_BUTTONS_OK,
                                    (const gchar *)message);

>  "Il risultato e' 789"
>     dialog = gtk_message_dialog_new (NULL,
>                                   GTK_DIALOG_DESTROY_WITH_PARENT,
>                                   GTK_MESSAGE_INFO,
>                                   GTK_BUTTONS_OK,
>                                   message);
>    /*now message is "Il risult(" 
>    gtk_window_set_position(GTK_WINDOW(dialog),GTK_WIN_POS_CENTER_ALWAYS);
>    gtk_dialog_run (GTK_DIALOG (dialog));
>    gtk_widget_destroy (dialog);
>    /*this call causes a segfault because message pointer changed his
> value */
>     free(message);
>    return;
>
> -- 
>
>
> Mio blog: http://newbufferedwriter.blogspot.com/
> http://prodigious.altervista.org/Scrobblit/index.php
>
>
> _______________________________________________
> gtk-list mailing list
> gtk-list gnome org
> https://mail.gnome.org/mailman/listinfo/gtk-list


-- 
Hofstadter's Law:
"It always takes longer than you expect, even when you take into account
Hofstadter's Law."