python exception in MISRA rule 8.12

[Richard Smith]

I'm receving the follwing execption using MISRA checker in d4d9bb4830a9198c161e82ef81dd1d0d6c6cef92
I've not yet dug into what source code is generating the exception.

Traceback (most recent call last):
File "/usr/bin/misra.py", line 2497, in <module>
main()
File "/usr/bin/misra.py", line 2440, in main
checker.parseDump(item)
File "/usr/bin/misra.py", line 2280, in parseDump
self.misra_8_12(cfg)
File "/usr/bin/misra.py", line 930, in misra_8_12
if not e_token.previous.str in ',{':
TypeError: 'in <string>' requires string as left operand, not instance</string></module>

[versat]

Hmm, we could add a sanitiy check to verify that e_token.previous.str really is a string, but i think it would be better to know what caused e_token.previous.str to be no string.
Is the code compilable? Maybe there is some compiler specific code at that place?

[versat]

I have found code that causes such an exception:

enum e { e1 = sizeof(int), e2};

This is valid compilable code, but it causes misra.py to throw an exception:

  File "../misra.py", line 2286, in parseDump
    self.misra_8_12(cfg)
  File "../misra.py", line 903, in misra_8_12
    if not e_token.previous.str in ',{':
TypeError: 'in <string>' requires string as left operand, not instance

[versat]

I created a ticket: https://trac.cppcheck.net/ticket/9208
If you find another maybe similar problematic code we can add it there or create another ticket.

[Richard Smith]

Yes the code compiles.

It seems to associated with code that uses this macro.

enum KernelUnawareISRs
{
    GPIO_WAKE_IRQ_PRIORITY = (0u >> (8u - __NVIC_PRIO_BITS)),
    MAX_KERNEL_UNAWARE_CMSIS_PRI
};

Where #define __NVIC_PRIO_BITS          4

is something included from an ARM CMSIS hardware support .h file

The enum is used this way:

    NVIC_SetPriority(GPIOWAKE_IRQn, GPIO_WAKE_IRQ_PRIORITY);

I know the (0u >>) looks odd but its part of a general form of computing interrupt prioritys. The 0u could be 1,2,3,... etc.

If I do a print(e_token.str) when checking the .c file containg this code then GPIO_WAKE_IRQ_PRIORITY is printed before the exception occurs.

[Richard Smith]

Looks like this got fixed in master. Thank you. Now I can make more progress on moving to newer cppcheck.