add: gdk_gc_unref(local_gc);
context: gerbv_draw_prim1(GdkPixmap *pixmap, GdkGC *gc, stack_t *s, int scale,		 gint x, gint y){    const int diameter_idx = 2;    /*      * Non filled circle      */    gerbv_draw_circle(pixmap, gc, 0, x, y,		      s->stack[diameter_idx] * scale);    return;} /* gerbv_draw_prim1 */