How to provide #defines to misra checking in cppcheck?

I'm trying to utilize misra C:2012 checking in from cppcheck (v2.9). However, when executing on a particular file I get the following violations:

vehicle_controller.c:1494:2: style: All identifiers used in the controlling expression of #if or #elif preprocessing directives shall be #define’d before evaluation. [misra-c2012-20.9] #if OS == LINUX_OS ^ src/emb/bwk/

I'm using the following command to execute:

$ cppcheck -DOS=LINUX_OS --addon=misra.json vehicle_controller.c

Is there a different way to pass #define to be properly picked up by the misra checking?

Solution

As per the examples within Rule 20.9, an undefined identifier results in a zero value:

#if OS == 0    /* Non-compliant - OS may be zero or undefined */
...
#endif

The MISRA compliant approach is to ensure that the identifier is defined before use. Thus:

#ifndef OS
...                   /* OS is undefined           */
#else
  #if OS == 0
  ...                 /* OS is defined as zero     */
  #else
  ...                 /* OS is defined as non-zero */
  #endif
#endif