What is the minimal approach to build only qhelpgenerator from source (5.15)?

devjb

Hi,

I am going crazy while trying to build the qhelpgenerator binary from source.

I build Qt from source inside a docker image to use as build environment in my ci. The configuration that I used for 3 years was reduced to increase build time and produce everything I need for my environment:

../configure -nomake examples -no-gui -no-eglfs -skip wayland -skip qt3d -skip qtquick3d -skip webview -skip qtwebengine -opensource -confirm-license

That build takes my ci about 12 minutes to finish.

When I use that resulting environment to build my application code, I get a set of code documentation from doxygen which provides a *.qhp file which I then need to pass through qhelpgenerator to finally get a qhc file which I then can load in qtcreator.

However, the qhelpgenerator tool is not buiilt using the above configuration.

From all my findings in the last few days I conclude that it is apparently not possible to get a qhelpgenerator binary that matches my environment unless I omit the no-gui option when I configure the build.

I need to build qtbase with all the gui overhead to be able to build qt assistant which then gives me a qhelpgenerator binary.

The issue with that is that the build takes really long and produces a whole lot of unneeded libs and binaries.

So I am looking for a solution how to get qhelpgenerator built with minimal dependencies.

Any tips how to achieve that?

jeremy_k

The qhelpgenerator output isn't specific to a particular Qt platform. I also haven't seen any problems using an earlier 5.15.x build with later 5.15.x QHelpEngine runtimes. My solution has been to create a static build, and copy the executable to the build system.

ChrisW67

@devjb qhelpgenerator is built with assistant. Both assistant and qhelpgenerator depend on help which, in turn, depends on the Qt gui and widgets modules.

So, in short, you cannot without hacking on Qt sources. I don't see the point anyway; you are saving, say, a few minutes every few months when Qt is updated.

jeremy_k

The qhelpgenerator output isn't specific to a particular Qt platform. I also haven't seen any problems using an earlier 5.15.x build with later 5.15.x QHelpEngine runtimes. My solution has been to create a static build, and copy the executable to the build system.

devjb

@ChrisW67

I am more experiencing an increase of two hours in build time than just a few minutes. And that is with 20 parallel jobs.

I would not care about a few minutes.

Anyway, I now for the sake of simplicity went by installing the qhelpgenerator binary standalone from the base systems package management and use that instead.

Similar to using @jeremy_k approach.

Christian Ehrlicher

I don't understand why someone has to recompile Qt everytime he wants to compile it's own application though.

devjb

That's not the case here. Qt is only rebuilt wenn the container it lives in is updated.