Core dumped... WHY?

[fahedsl]

Hello, I am teaching myself some programming, and Im working on a small program, on Geany with GTK+ 3, Mariadb and mysql++. I'm sure all of them are working fine.
I'm experimenting a bit with functions, because i'm new to the language, soo i did this(supossed to show an empty window, with an invisible grid):



// Cabeceras#include <mysql++/mysql++.h>
#include <iostream>
#include <iomanip>
#include <gtk/gtk.h>


// Nombres (evita ::)
using namespace std;
using namespace mysqlpp;


//Globales
GtkWidget *wventana;


//DEFINICIONES


int ventana(string titulo, int margen)
{
const char * tituloc = titulo.c_str();


wventana = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_position (GTK_WINDOW (wventana), GTK_WIN_POS_CENTER);
gtk_window_set_title (GTK_WINDOW (wventana), tituloc);
gtk_container_set_border_width(GTK_CONTAINER(wvent ana), margen);
return 0;
}


int grid()
{
GtkWidget *grid;


grid = gtk_grid_new();
gtk_container_add(GTK_CONTAINER(ventana), grid);
return 0;
}


//INICIO
int main(int argc, char *argv[])
{
//INICIO GTK
gtk_init (&argc, &argv);


//Widgets
ventana("ventana",10);
grid();


//mostrar todo gtk
gtk_widget_show_all (wventana);
gtk_main ();


return 0;
}


It compiles successfully with this instructions :


g++ -Wall -I/usr/include/mysql -I/usr/local/include/mysql++ -o "%e" "%f" `pkg-config --cflags --libs gtk+-3.0`

(%e and %f are file names completed automatically by Geany), but when I try to run the program, it shows:


Segmentation fault (core dumped)

Please, someone tell me why that is happening and/or how to fix it.
Thanks in advance.

[lisati]

Duplicate of http://ubuntuforums.org/showthread.php?t=2239459 closed in the interests of not diluting the community's ability to help.