project = test
outputdir   = html
headers = a.h
sources = a.cpp
headerdirs  = .
sourcedirs  = .

class A {
public:
    A() {}

    void f() { }
    void g();
    void h();
};

#include "a.h"

/*!
  \class A
  \brief Powerful class for doing A.
  \inmodule test

  A is a class.
 */

void A::g()
{

}

/*!
  Does h() on a A class
 */
void A::h()
{
}

C:\dev\tmp\qtbug-104614>C:\Qt\6.3.0\msvc2019_64\bin\qdoc.exe qdocwarnings.qdocconf
qt.qdoc: Start qdoc for test in dual process mode: generate phase.
qt.qdoc: No include paths passed to qdoc; guessing reasonable include paths
(qdoc) Could not find the module header in include paths for module "test"   (include paths:  QList() )
       Artificial module header built from header dirs in qdocconf file
qt.qdoc: Parse source files for "test"
qt.qdoc: No include paths passed to qdoc; guessing reasonable include paths
qt.qdoc: Source files parsed for "test"
qt.qdoc: End qdoc for test in dual process mode: generate phase.