Despite skipping a *.pro file via qtHaveModule(quick), qmake fails due to missing gui module

devjb

Hi,

i have QT += quick in one of my qmake project files. Because I build several projects within my subdirs project, I want certain target environments to compile only the stuff that does not depend on graphical stuff because the targets are headless.

So I decided to entirely skip the build of the gui dependent pro files via

qtHaveModule(quick){
DEFINES += \
	BLABLA_UI_LIBRARY
QT += quick

[...]
}
else
{
message("QtQuick not available, skipping building the blabla-ui lib")
}

However those headless systems fail to run qmake. They successfully print the error message that quick is not available and afterwards fail nonetheless:

Project MESSAGE: QtQuick not available, skipping building the blabla ui lib
Project ERROR: Unknown module(s) in QT: gui

Any ideas what to do further? Thanks in advance.

The full log, starting with the skip is here:

https://gist.github.com/darkmattercoder/e82b62638ec76597fb7365e1cf404275

KroMignon

@devjb said in Despite skipping a *.pro file via qtHaveModule(quick), qmake fails due to missing gui module:

Project ERROR: Unknown module(s) in QT: gui

If you don't you gui, you should insert in your PRO file QT -= gui

qtHaveModule(quick){
DEFINES += \
	BLABLA_UI_LIBRARY
QT += quick

[...]
}
else
{
    message("QtQuick not available, skipping building the blabla-ui lib")
    QT -= gui
}

devjb

Well, that was a quick and obvious fix... worked

However, I do not understand why the error appears in the first place. Because qmake should not process the file at all.
I have several other project files, some of them contain QT-=gui and some of them don't, however they all build successfully, even those where I did not put that in.

Furthermore, the project file in question is practically empty beside the qthavemodule check, so why tries qmake to do something else afterwards.

I simply want to get at least a kind of understanding of what goes on here.

KroMignon

@devjb said in Despite skipping a *.pro file via qtHaveModule(quick), qmake fails due to missing gui module:

I simply want to get at least a kind of understanding of what goes on here.

As describe here ==> https://doc.qt.io/qt-5/qtgui-index.html
GUI module is included by default and must be removed if not required/used

devjb

@KroMignon thanks for the clarification

Well, my approach was even wrong in the first place.
What I wanted to achieve is done via one line in the *.pro file:

requires(qtHaveModule(quick))

this is was I was looking for and gives me the correct results that I am expecting.

KroMignon

@devjb said in Despite skipping a *.pro file via qtHaveModule(quick), qmake fails due to missing gui module:

this is was I was looking for and gives me the correct results that I am expecting.

Sorry, I have readed too fast your post! Yes, using requires() is the right way to do what you want!