Strange "! Missing = inserted for \ifnum." Error

[huxuan]

Currently, we will encounter compile error like below.

! Missing = inserted for \ifnum.
<to be read again> 
                   0
l.5 \thesisauthor
                 {张三}{ZhangSan}
?

We should absolutely solve it.

[huxuan]

After some try, I found it‘s not related to thesisauthor itself but rightly after documentclass declaration.
Seems to be a really hidden bug.
@JosephPeng Do you have any progress or suggestions for this bug？

[JosephPeng]

呃，这个bug可真有些奇葩，我再测试几次吧，不行就把buaa@thesisauthor换个名字好了。

[huxuan]

@JosephPeng 我试过了，和buaa@thesisauthor没有关系，就算删掉了，也会报下一行的错，应该是运行documentclass就产生的问题，不过看了一会没看出来问题可能在哪