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I need to solve misra related issues and cert related issues

uint8_t      globalRegion;
uint8_t      tcc;
uint16_t     paramId;
globalRegion = 9U;

If I remove U i get misra etype assign error stating that usgined int is compared with signed value .

globalRegion = 9;

But if i add U I am getting error STRONG.TYPE.ASSIGN.CONST A value '9U' is assigned to the strongly typed variable 'globalRegion' of type 'uint8_t'

globalRegion = 9U;

If TYPECASTED will get another error porting.cast.size Cast of an expression to a type of potentially incompatible size

globalRegion = ((unit8_t)9U);

how to resolve this error without getting any new error

Andrew
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swethasree
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    The message you claim to get doesn't match the code. Are you sure the message (about *comparison*) is for that line (with the *assignment*)? What tool are you using for the MISRA checks? Please try to create a proper [mre] to show us, and copy-paste the exact messages you get into the question. – Some programmer dude Aug 24 '22 at 07:22
  • We are checking the code against MISRA C 2012 and cert C coding standard. how to represent 9 as bit without adding U to it . If I add U klocwork will treat U as 32 bit and gives me error. – swethasree Aug 24 '22 at 07:55

1 Answers1

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globalRegion = 9U; is MISRA compliant. An uint8_t belong to the type group "essentially unsigned" so it is correct and required by MISRA to use U suffix when assigning an integer constant to that variable.

It would appear that some Klocwork-specific thing STRONG.TYPE.ASSIGN.CONST is meant to warn about using so-called "magic numbers". It doesn't seem to have anything to do with the 'U' as such. It is widely recognised that using magic numbers in code is considered bad practice, though I can't recall that MISRA or CERT has an explicit rule against them.

You could try to do globalRegion = meaningful_name; instead, where meaningful_name should be replaced some sensibly named constant. You could try to either do it in the form #define meaningful_name 9U or const uint8_t meaningful_name = 9U;.

On the other hand, the Klocwork manual is babbling about "ANSI" as if it's still the year 1989, so that manual isn't exactly building up confidence in the correctness and usefulness of that tool...

Lundin
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