Long Chars

[Alan J Rosenthal]

I, flaps at dgp.toronto.edu (Alan J Rosenthal) wrote:

>>Why do you need to make sizeof(char) == 2 just to make chars 16 bits?
>>Make chars 16 bits, keep sizeof(char) == 1, make sizeof(int) == 1, ...

gwyn at brl.arpa (Doug Gwyn) responded:

>The idea is that you not only need to handle fat chars, you also
>have applications that need to handle smaller objects (bytes, or
>bits).  Therefore there would have to be some object type smaller
>than a char (e.g. a "short char").

I now respond:

First of all, why would you possibly want to access bytes?  Bytes are
machine-dependent things with no high-level analogue.  You certainly
might want to access some object which is small enough to use for
traversing an arbitrary object.  16-bit chars would still have this
property so long as all objects were a multiple of 16 bits long.

As for being able to access bits, sizeof(char) would have to be equal
to 8 or 16 for that, not just 2.  Also, creating smaller objects than
chars will cause a lot of other problems, such as requiring either
introducing the concept of alignment into the language (e.g. arguments
to memcpy must be char-aligned) or making the arguments to routines
like memcpy be pointers to this smaller object at the expense that that
incurs.

ajr
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