Question about -ansi flag, and different size of struct from C and C++
Oleg Ivanov
Belinus at zelax.ru
Mon Dec 15 15:34:15 UTC 2003
Ralf Corsepius пишет:
>On Mon, 2003-12-15 at 15:18, Oleg Ivanov wrote:
>
>
>> Thanks a lot!
>>
>> Yes, I also see #pragma warning: ignoring pragma: even if I compiling
>>with or without -ansi flag.
>> And another thing, I compile code under two targets Motorola 68360
>>and 860.
>> In one point compiler aligned all struct to 4, in other every struct
>>member.
>> That mean size of struct
>> struct dummy {
>> int var1;
>> short var2;
>> int var3;
>> short var4;
>> }
>> on motorola 68360 will be 12 byte, and on 860 - 16 byte...
>>Is it also target dependent ?
>>
>>
>Yes, it is.
>
>But what is your actual problem? Size (eg. allocating large arrays), or
>IO?
>
>Ralf
>
>
>
It's more IO, but and size too.
From Rtems I controle hardware that accept about 30 packets(each with
fix length) with several(to 32) commands with parameters(full packet
send even all or only one command is set), so I think that easy way to
handle this zoo is to make a struct to each packet. But as I say got
this problem, size changes and command rejected, and also packet work
only from C, from C++ it not work. It's work only when I ommit -ansi flag.
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