从不兼容的指针类型传递“gtk_label_set_selectable”的参数 1

问：

我试图学习GTK编程。我用 c 编写了一个简单的程序。我正在尝试将指向标签的指针传递给 gtk_label_set_selectable（） 函数，但我收到此警告：

#include <gtk/gtk.h>
#include <stdlib.h>

long i = 1;

void showadd(short u,GtkWidget *l)
{
    char * s;
    s = (char*)malloc(20);
    sprintf(s,"%ld",++i);
    gtk_label_set_text(GTK_LABEL(l),s);
}

int main (int argc, char *argv[])
{
    gtk_init(&argc,&argv);
    GtkWidget * win,* lable, * addButton,* SubstractButton,*box;

    win = gtk_window_new(GTK_WINDOW_TOPLEVEL);

    addButton = gtk_button_new_with_label("+");
    lable = gtk_label_new("1");
    box = gtk_vbox_new(0,0);

    g_signal_connect(win,"delete-event",G_CALLBACK(exit),NULL);
    g_signal_connect(addButton,"clicked",G_CALLBACK(showadd),(gpointer)lable);
    gtk_label_set_selectable(lable,1); //getting warring here

    gtk_container_add(GTK_CONTAINER(win),box);
    gtk_box_pack_start(GTK_BOX(box),lable,1,0,0);
    gtk_box_pack_start(GTK_BOX(box),addButton,1,0,0);
    gtk_widget_show_all(win);

    gtk_main();
}

当我在eclipse CDT中编译它时，我在控制台中收到此警告：

../src/Calculator.c:35:28: warning: passing argument 1 of ‘gtk_label_set_selectable’ from incompatible pointer type [-Wincompatible-pointer-types]
   gtk_label_set_selectable(lable,1);
                            ^~~~~

我应该忽略此警告吗？如果没有，那么我能做些什么来让它消失？如果是，那么我怎样才能让日食消失。