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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: remark on defining size of basic types
Date: Thu, 04 Apr 2024 22:22:23 -0700
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James Kuyper <jameskuyper@alumni.caltech.edu> writes:
> On 4/4/24 13:04, Michael S wrote:
>> On Thu, 4 Apr 2024 12:02:16 -0400
>> James Kuyper <jameskuyper@alumni.caltech.edu> wrote:
>> 
>>> On 4/4/24 09:15, Janis Papanagnou wrote:
>>> ...
>>>> Since I remember C had always just defined a '<=' (or '>=') relation
>>>> between the unsized basic integral data types.  
> ...
>> He meant sizeof(short) <= sizeof(int) <= sizeof(long) <= sizeof(long
>> long)
>
> That's not actually the case. In the above, you are not using <= as the
> C operator, but simply to indicate relative order over multiple items; I
> will do the same. What is specified is equivalent to the following
>
> LONGLONG_MIN <= LONG_MIN <= INT_MIN <= SHORT_MIN <= SCHAR_MAX
> SCHAR_MAX <= SHORT_MAX <= INT_MAX <= LONG_MAX <= LONGLONG_MAX
> UCHAR_MAX <= USHORT_MAX <= UINT_MAX <= ULONG_MAX <= ULONGLONG_MAX
>
> SCHAR_MAX <= UCHAR_MAX
> INT_MAX <= UINT_MAX
> LONG_MAX <= ULONG_MAX
> LONGLONG_MAX <= ULONGLONG_MAX

SHRT, not SHORT.
LLONG, not LONGLONG.

> The sizes are not required to be in the same order as the maximum
> values, nor in the opposite order of the minimum values. If they were in
> a different order, it would imply a lot of padding bits, which would be
> very odd, but not prohibited.

For completeness, the way it's described in the standard (quoting N3220
6.2.5p10-11) is :

    For any two integer types with the same signedness and different
    integer conversion rank (see 6.3.1.1), the range of values of the
    type with smaller integer conversion rank is a subrange of the
    values of the other type.

    The range of nonnegative values of a signed integer type is a
    subrange of the corresponding unsigned integer type, and the
    representation of the same value in each type is the same.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Medtronic
void Void(void) { Void(); } /* The recursive call of the void */