Luca Fancellu - 2022-12-22

Hi,
I hope this is the right place to post this finding, the Xen project is starting to use cppcheck for MISRA analysis, we've found some false positive that we would like to report.

In this post I would like to report a false positive for the rule 20.7, in this example the misra addon is complaining about the lack of parenthesis for the "f" argument of the macro, but adding them will result in syntax errors.

I'm using Cppcheck 2.7

Report:

prova.c(6,0):misra-c2012-20.7:style:misra violation (use --rule-texts=<file> to get proper output)

prova.c

struct a_struct {
    int member;
};

#define ACCESS_MEMBER(a,f) ((a)->f)

int main(void)
{
    struct a_struct the_struct = {0};
    struct a_struct *pointer = &the_struct;
    int num;

    num = ACCESS_MEMBER(pointer,member);
    (void)num;
}

cppcheck-misra.json:

{
    "script": "misra.py",
    "args": []
}

Here the command line I've used to reproduce it:

cppcheck --cppcheck-build-dir=build-dir-cppcheck \
    --max-ctu-depth=10 \
    --enable=style,information,missingInclude \
    --template='{file}({line},{column}):{id}:{severity}:{message}' \
    --output-file=report.txt \
    --addon=cppcheck-misra.json \
    prova.c
 

Last edit: Luca Fancellu 2022-12-22