stack/stack.go
func (c *Call) equal(r *Call) bool {
	return c.SrcPath == r.SrcPath && c.Line == r.Line && c.Func == r.Func && c.Args.equal(&r.Args)
}
func (c *Call) equal(r *Call) bool {
	return c.SrcPath == r.SrcPath && c.Line == r.Line && c.Func == r.Func && c.Args.equal(&r.Args)
}
// equal returns true only if both calls are exactly equal.