sizeof(uchar**) vs sizeof(uchar*)

[qihua wu]

In the source code of mysql,
sizeof(uchar**) is used like:
recbuffer= (uint) (reclength + sizeof(uchar**) - 1) & ~(sizeof(uchar**) - 1);

sizeof(uchar*) is used like:
keyseg->length= sizeof(uchar*);

In C, the size of a pointer should be the same. So the size of pointer to a uchar should be the same as the size of a pointer to a pointer (to a uchar). In this way, sizeof(uchar*) should be the same as sizeof(uchar**). Am I right?