数组衰减为指针的异常？

Sure.

In C99 there are three fundamental cases, namely:

1. when it's the argument of the & (address-of) operator.

2. when it's the argument of the sizeof operator.

3. When it's a string literal of type char [N + 1] or a wide string literal of type wchar_t [N + 1] (N is the length of the string) which is used to initialize an array, as in char str[] = "foo"; or wchar_t wstr[] = L"foo";.

Furthermore, in C11, the newly introduced alignof operator doesn't let its array argument decay into a pointer either.

In C++, there are additional rules, for example, when it's passed by reference.