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My question is if the code bellow is not compliance with misrac-2004

uint16_t GetSpeed (void);
void IncreaseSpeed (void);
void DecreaseSpeed (void);
void GoodSpeed (void);

enum tagSPEED
{
Low,
Medium,
High
};

void main (void)
{
uint16_t uSpeed;

uSpeed = GetSpeed();

switch (uSpeed)
{
case Low:
IncreaseSpeed();
break;

case Medium:
GoodSpeed (void);
break;

case High:
DecreaseSpeed (void);
break;

default:
break;
}
}

Is there any solution for this case?


Normative reference:
Ansi-Iso-9899-1990 (6.5.2.2)
Misra-c2004 (6.10.3)

I just want to know when a cast shall be performed between a pointer to void and any type or vice versa?

for example is this code compliance with misra-c?

void* GetNewObject (void);
void SetProperty (void*, uint8_t);

void main (void)
{
void* lpVoid;
OBJECT_T* lpObject;

lpVoid = NULL;
lpObject = NULL;

lpObject = GetNewObject ();
/* there is an explicit cast in
this function from OBJECT_T*
type to void* type, so GetNewObject
return an OBJECT_T* qualifier type */

lpVoid = lpObject;

SetProperty (lpVoid, 4U);

lpObject = lpVoid;

if (lpObject == lpVoid)
{
SetProperty (lpObject, 5U);
}

lpVoid = lpObject;
}

My question is why my code test program (lint) generate an error when read this line.

U16 u16value;
U8 u8value;

u16value = (U16) u8value / 10U;

I think that line is absolutly compliance with misrac.

but in other hand this other line does not generate an error, but i think that it is not misra compliance.

U16 u16value;
U8 u8value;

u8value = (U16) u8value / (U16)10U;

I would like to know how to represent a Violation of rule 12.12.
It is stated in C90 that bitwise operands are required to of integer type. Therefore bitwise operators can't be used with floats to demonstrate this rule as this would be a direct violation of rule 1.1.

Is maybe pointer indirection using an unsigned char the answer?

or are there implementations that allow bitwise operators to be used with floats?

Thanks for your help!

Hello,

I use a tool, which tested code to MISRA-C:2004 compliance.

Here is a code example, on which our analyse tool says, there is a breach of rule 21.1.

Hello

I use unions in the following example. And I want to know, if in such a situation the use of unions is compliant or not compliant to MISRA-C:2004. Or if somebody has a better idea for a good implementation.

Hi

Two questions about this rule:

1. Have somebody examples short for function-like macros?
2. When is a macro funktion-like?

best regards,
Manni

Hi

Question about Rule 12.9: The unary minus operator shall not be applied to an expression whose underlying type is unsigned.

Hi

I want to start writing a helping document and tutorial about MISRA-C:2004 rules. The document should contain the following points.

1. Reasons for specific MISRA-C rules. (Why is it important to observe the rule)
2. Howto handle specific rules
3. Howto conceive specific rules
4. Exampels for breaches of the specific rules, and how to solve it. (with example, too)

Are there any good sources and publications, which helping to write such a tutorial?

best regards,
Manni

EDIT:
I know that there are explanations like this in miscra-c rules included. But I mean more comprehensive explanation.

This new forum has been set up for asking questions about and discussing MISRA's \"Software Readiness for Production\" guidelines.