evaluate: sizeof(bool) could be larger than sizeof(char)

The C standard doesn't require that the size of a _Bool is 1,
its size is implementation defined.

However, in evaluate_sizeof() the assumption is made that
a bool is the same size as a char.

Fix this wrong assumption by using the existing bits_in_bool.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
1 file changed