I am running cppcheck with misra_c2012 on my project and I have an issue with the :preprocessor: part in cppCheck.yml. All the code is analysed on my .c file, even the part only defined under certain conditions (#ifdef MACRO1) but I dont have the same behaviour on the header, where only the code common to every MACRO is analysed.

I made an small piece of code to illustrate my problem:

test.h

void test_noConfiguration(void);

#if defined(CONFIG_1) 
void test_configuration1(void);
#endif

#if defined(CONFIG_2)
void test_configuration2(void);
#endif

test.c

#include "test.h"

static uint8_t localFunction(void)
{
    return 0U;
}

void test_noConfiguration()
{
    localFunction();
    uint8_t u8_var = 0U;
}

#if defined(CONFIG_1)
void test_configuration1()
{
    localFunction();
    uint8_t u8_var = 0U;
}
#endif

#if defined(CONFIG_2)
void test_configuration2()
{
    localFunction();
    uint8_t u8_var = 0U;
}
#endif

When the analyse is launched with the macro CONFIG_1 defined on the :preprocessor: part of the cppCheck.yml, all the issues are raised except for the one between #if defined(CONFIG_2), both in the .c and .h files, as expected.

When the analyse is launched without any macro defined on the :preprocessor: part of the cppCheck.yml, all the issues of test.c are raised but in test.h, only the one outside #ifdef CONFIG_1 or #ifdef CONFIG_2 are raised (here, only the line with declaration of void test_noConfiguration(void); raised the error misra-c2012-8.2 in test.h)

I was wondering, when there is not any macro defined in the cppCheck.yml, if it was supposed to :

• analyse all the code.
• analyse only the code ouside of all the #ifdef.

Either way, it seems odd that the behaviour is not the same in the .c and .h.

Thank you for you help