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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: C23 thoughts and opinions
Date: Sat, 01 Jun 2024 17:26:41 -0700
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jak <nospam@please.ty> writes:

> bart ha scritto:
>
>> On 01/06/2024 02:37, jak wrote:
>>
>>> bart ha scritto:
>>>
>>>> I can see that the first two can be subtracted to give the sizes
>>>> of the data, which is 70 or 0x46. 0x46 is the last byte of the
>>>> address of _size, so what's happening there?  What's with the crap
>>>> in bits 16-47?
>>>>
>>>> I can extract the size using:
>>>>
>>>>  printf("%d\n", (unsigned short)&_binary_hello_c_size);
>>>>
>>>> But something is not right.  I've also asked what is the point of
>>>> the -size symbol if you can just do -end - -start, but nobody has
>>>> explained.
>>>
>>>  typedef unsigned char uchar;
>>>  extern uchar _binary_hello_c_size[];
>>>  long hello_c_size = _binary_hello_c_size - (uchar *)0;
>>
>> What result for the size did you get when you ran this?
>>
>> It seems people are just guessing what might be the right code and
>> posting random fragments!
>
> I wrote it that way precisely because I believed it was the clearest
> way.  [...]

What is most clear is that the expression used has undefined
behavior.