[cfe-dev] Checking if a ParmVarDecl is null in a Checker

[Timothy J. Wood via cfe-dev]

> On Apr 24, 2018, at 5:07 PM, Artem Dergachev <noqnoqneo at gmail.com> wrote:
> 
> I still strongly encourage you to have a look at the exploded graph. It'll immediately explain the whole analysis step-by-step to you and show you everything that's available on every step and you won't have to blindly experiment with random callbacks anymore. Please ask if you'll have problems understanding it.

For extremely simple examples, the exploded graph is sort of tractable, but in large cases it is difficult to figure out what is going on. Maybe I missing something but I’d find it much more useful if I could find a way to:

- Have my custom state (registered with REGISTER_MAP_WITH_PROGRAMSTATE) be logged in the nodes
- Have error nodes marked red
- Have newly added/updated/removed state called out with some style changes (bold blue for added, bold black for updated, red for removed?)
- Add log messages of findings in my checker callbacks on the ProgramState or ExplodedNode

These might be a project to tackle on their own, but if there are tips for getting some useful meaning out of the exploded graph, it would be helpful.

Thanks,

-tim