From: david.brown@hesbynett.no
On 11/01/2026 17:19, Michael S wrote:
> On Sun, 11 Jan 2026 16:34:28 +0100
> David Brown wrote:
>
>> On 11/01/2026 14:32, Michael S wrote:
>>> On Sun, 11 Jan 2026 04:59:47 -0800
>>> Keith Thompson wrote:
>>>
>>>> Michael S writes:
>>>>> On Sat, 10 Jan 2026 22:02:03 -0500
>>>>> "James Russell Kuyper Jr."
>>>>> wrote:
>>>>>> On 2026-01-09 07:18, Michael S wrote:
>>>>>>> On Thu, 8 Jan 2026 19:31:13 -0500
>>>>>>> "James Russell Kuyper Jr."
>>>>>>> wrote:
>>>>>> ...
>>>>>>>> I'd have no problem with your approach if you hadn't falsely
>>>>>>>> claimed that "It is correct on all platforms".
>>>>>>>
>>>>>>> Which I didn't.
>>>>>>
>>>>>> On 2026-01-07 19:38, Michael S wrote:
>>>>>> ...
>>>>>> > No, it is correct on all implementation.
>>>>>
>>>>> The quote is taken out of context.
>>>>> The context was that on platforms that have properties (a) and (b)
>>>>> (see below) printing variables declared as uint32_t via %u is
>>>>> probably UB according to the Standard (I don't know for sure,
>>>>> however it is probable),
>>>>
>>>> I'm sure. uint32_t is an alias for some predefined integer type.
>>>>
>>>> This:
>>>> uint32_t n = 42;
>>>> printf("%u\n", n);
>>>> has undefined behavior *unless* uint32_t happens to an alias for
>>>> unsigned int in the current implementation -- not just any 32-bit
>>>> unsigned integer type, only unsigned int.
>>>>
>>>> If uint32_t is an alias for unsigned long (which implies that
>>>> unsigned long is exactly 32 bits), then the call's behavior is
>>>> undefined. (It might happen to "work".)
>>>>
>>>
>>> What exactly, assuming that conditions (a) and (b) fulfilled, should
>>> implementation do to prevent it from working?
>>> I mean short of completely crazy things that will make maintainer
>>> immediately fired?
>>
>> If an architecture has 32-bit "unsigned long", then "unsigned int" is
>> necessarily also 32-bit (since "unsigned int" is always at least
>> 32-bit,
>
> I am pretty sure that it is wrong.
> C Standard does not require for 'unsigned int' to be above 16 bits.
>
Sorry, I jumbled that. It is unsigned long that must be at least 32
bits, so your second requirement is not redundant.
>> and "unsigned long" cannot be smaller than "unsigned int").
>> The very fact that you listed "unsigned int is at least 32-bit wide"
>> as an assumption shows you are not well versed with the basics of C
>> standards in this area.
>>
>
> I am not well versed in the Standard. But in this particular case you
> are the one who doesn't know it.
>
I know it, but I still got it wrong here :-(
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* Origin: you cannot sedate... all the things you hate (1:229/2)
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