[PATCH] score: _Objects_Build_name() signed/unsigned char

[Gedare Bloom]

On Tue, Feb 2, 2021 at 9:57 AM Gedare Bloom <gedare at rtems.org> wrote:

>
>
> On Tue, Feb 2, 2021 at 9:44 AM Sebastian Huber <
> sebastian.huber at embedded-brains.de> wrote:
>
>> On 02/02/2021 17:22, Gedare Bloom wrote:
>>
>> > OK. This one surprised me (and I'm sure I'm not the only one.)
>> >
>> > On Tue, Feb 2, 2021 at 7:42 AM Sebastian Huber
>> > <sebastian.huber at embedded-brains.de
>> > <mailto:sebastian.huber at embedded-brains.de>> wrote:
>> >
>> >     Change _Objects_Build_name() so that the result is independent of
>> the
>> >     signedness of char.
>> >
>> >     Close #4228.
>> >
>> I don't think it is practically an issue, however, if you want to
>> specify this function, then it gets a problem. You would have to write
>> something like: Where the char is signed, ...
>>
>>
> Maybe. I wrote a simple program because I was curious about this behavior.
> int main(int argc, char *argv[])
> {
>   unsigned char a = 0xff;
>   signed char b = 0xff;
>
>   printf("(uint32_t)a: %u\n(uint32_t)b %u\n", (uint32_t)a, (uint32_t)b);
>
>   printf("(uint32_t)(uint8_t)a: %u\n(uint32_t)(uint8_t)b %u\n",
>       (uint32_t)(uint8_t)a, (uint32_t)(uint8_t)b);
>
>   return 0;
> }
>
> $ ./a.out
> (uint32_t)a: 255
> (uint32_t)b 4294967295
> (uint32_t)(uint8_t)a: 255
> (uint32_t)(uint8_t)b 255
>
>
> So, you would get some maybe unpleasant behavior if you have a signed char
> in the less-significant bytes that you end up sign-extending through the
> more significant bytes.
>
>
Only a problem if one uses non-ASCII (extended) characters though. So not a
real problem in practice.


>
>
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