As of commit 7cd150fe609b606f259af18fc98d34b4fbde20a7, the gcc-with-cpychecker harness now invokes the reference-count checker, removing the need to hack up libcpychecker/__init__.py to do this. So now you can invoke the checker on arbitrary CPython extension code (e.g. gdb) with something like: make CC=/path/to/built/plugin/gcc-with-cpychecker without having to hack up the checker's code: you'll get a GCC with the extra "cpychecker" compilation pass, which runs these tests: * format checking of Py_ArgParse* and Py_BuildValue calls * reference count analysis Having said that, expect to run into tracebacks and other bugs with the checker if you do (including incorrect reports - so proceed with caution!). I'm still slowly working through gdb and the plugin's code with the checker, fixing issues as I see them. Adding some kind of custom attributes to mark functions that steal references (and those that return borrowed references) is probably next. Dave