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64 bit data types?

Posted: Fri Sep 22, 2006 1:05 pm
by mhabermann
Hello!

Rule 6.3 of MISRA-C lists the typedefs for uint64_t and int64_t, which I believe are not used anymore in the standard and should be disallowed by C90.

Can you confirm that uint64_t and int64_t datatypes are not allowed?


Best Regards

Michael

Re: 64 bit data types?

Posted: Sat Sep 23, 2006 8:08 am
by phaedsys
Hi,
mhabermann wrote:Rule 6.3 of MISRA-C lists the typedefs for uint64_t and int64_t, which I believe are not used anymore in the standard and should be disallowed by C90.

Can you confirm that uint64_t and int64_t datatypes are not allowed?
My personal opinion is that if your environment has 64 bit ints then you can use uint64_t you can also use int128_t if there is one.

Whilst MISRA-C is based on C90 we are in a real world where there are 64 bit and 128 bit systems in use. There has been some discussion in other places where there are machines using 9 bits and 36 bits. The int**_t and uint**_t can cope with all of these.

MISRA-C is for the use for systems in the real world, not the theorectical world of ISO language standards.