8.9 and 3rd party library code

[misra-c]

Yes, Rule 8.9 does apply to 3rd party libraries (see Rule 3.6).

If you don't have the source code for the library then you can:

• write a stub that provides appropriate definitions in order to allow you to analyse your code; and
  
• ask the library's developer(s) to provide a statement regarding its MISRA C compliance.