供以后参考，这是因为在包括...之前，我没有#defined UNW_LOCAL_ONLY ...将其保留为未定义会导致选择不同的函数签名(也许是随机的)

For future reference, it is because I had not #defined UNW_LOCAL_ONLY before including ... Leaving it undefined lead to different function signature getting picked (at random perhaps).

http://www.nongnu.org/libunwind/man/libunwind(3).html