Can uint8_t be a non-character type?

Question

In this answer and the attached comments, Pavel Minaev makes the following argument that, in C, the only types to which uint8_t can be typedef\'d are char

Answer 1

If uint8_t exists, the no-padding requirement implies that CHAR_BIT is 8. However, there's no fundamental reason I can find why uint8_t could not be defined with an extended integer type. Moreover there is no guarantee that the representations are the same; for example, the bits could be interpreted in the opposite order.

While this seems silly and gratuitously unusual for uint8_t, it could make a lot of sense for int8_t. If a machine natively uses ones complement or sign/magnitude, then signed char is not suitable for int8_t. However, it could use an extended signed integer type that emulates twos complement to provide int8_t.