long_int vs int byte sizes
Corinna Vinschen
corinna-cygwin@cygwin.com
Mon Apr 7 14:42:00 GMT 2014
On Apr 7 08:16, Eric Blake wrote:
> On 04/07/2014 02:47 AM, Corinna Vinschen wrote:
>
> >
> > There's no standard which restricts the sizes of the datatypes in
> > that way. There's only this rule to follow:
> >
> > sizeof (char) <= sizeof (short) <= sizeof (int) <= sizeof (long)
>
> Well, there IS the C rule that sizeof(char)==1, and also that char holds
> >= 8 bits, short holds >= 8 bits, int holds >= 16 bits, long holds >= 32
> bits. There is also a POSIX rule that CHAR_BITS==8 (so while C allows a
> 9-bit or 32-bit char [and yes, such machines exist, although rare],
> POSIX does not allow that).
Apart from POSIX, where is that defined? The old K&R rules only defined
the sizes of the datatypes in comparison to each other, but it never
defined minimum sizes. If you have a 7 bit machine and you only use
ASCII, you can be happy ever after. And while it *suggested* that short
< long, it didn't demand it.
> POSIX does not allow that). But in general, on most modern porting
> platforms, 'long' is a redundant type - it will either be equal in size
> to 'int' (typical for a 32-bit machine) or to a 'long long' (typical for
> a 64-bit machine); it only mattered on 16-bit machines which are now
> museum pieces.
Xstormy16?
Corinna
--
Corinna Vinschen Please, send mails regarding Cygwin to
Cygwin Maintainer cygwin AT cygwin DOT com
Red Hat
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: <http://cygwin.com/pipermail/cygwin/attachments/20140407/993c8021/attachment.sig>
More information about the Cygwin
mailing list