Cpp clean tells me I need to #include something that I can forward declare. about cppclean HOT 5 OPEN

I can't reproduce this:

$ cat Foo.h
class Blah;
class Foo: public Bar{
public:
    Foo();
    virtual bool doSomething(Blah* blah);
};
$ ./cppclean Foo.h

from cppclean.

My examples wasn't good. I'll need to look further into this to work out what's going on, but may not have time. My project is very large so it could be very difficult to reduce it to a Minimal, Complete, and Verifiable example
Is there a chance that cppclean could give the reason behind its conclusions? Like, it says something needs to be #included, can it give the location of the code that requires the #include, as well as the location of the forward-declare that it gives now?

from cppclean.

I've got this kind of behaviour in specific templates.
Ex :

class Data;

class Toto {
QPointer<Data> _socket
}

QPointer stores a pointer, it doesn't need access to Data implementation.
This is the same for many smart pointers classes.

from cppclean.

Would something that was forward declared but needs to be included even compile?

from cppclean.

The following might help.

This works:

class MyCoolClass;

int do_something(MyCoolClass * ptr);

but this raises 'MyCoolClass' forward declared, but needs to be #included:

class MyCoolClass;

template <typename T>
T do_something(MyCoolClass * ptr)
{
    // whatever
    return 0;
}

from cppclean.