Qt Creator 6/7/8 (Qt 6) qmake doesn't exist isn't executable or has no output

[jarvis76]

Re: Qt Creator Qt Versions saying "qmake does not exist or is not executable"

I am having a similar issue on Rocky Linux 8.6

• QTC_USE_QPROCESS=1 doesn't fix the problem on 6.0.2/7.0.2/8.0.0 which use Qt 6.2.2 and up
• Using QTC_USE_QPROCESS=1 only causes Qt Creator to load a lot faster (or whenever it tries to run qmake, like when opening the preferences/options menu)
• I cannot open my CMake project because of this. It just lists CMakeLists.txt and not the project files

Version 6.0.2 (Qt 6.2.2 / GCC 10.3.1 20210422 / Red Hat 10.3.1-1) says:

qt.qpa.plugin: Could not find the Qt platform plugin "wayland" in ""
SOFT ASSERT: "match.hasMatch()" in file /home/qt/work/build/qt-creator/src/plugins/git/gitclient.cpp, line 3585
Cannot update Qt version information: /home/USER/Qt/6.3.1/gcc_64/bin/qmake cannot be run.
SOFT ASSERT: "false && "__cplusplus is not predefined, assuming latest C++ we support."" in file /home/qt/work/build/qt-creator/src/plugins/projectexplorer/toolchain.cpp, line 443

Version 7.0.2 (Qt 6.2.3 / GCC 10.3.1 20210422 / Red Hat 10.3.1-1) says:

Warning: Ignoring WAYLAND_DISPLAY on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
SOFT ASSERT: "match.hasMatch()" in file /home/qt/work/build/qt-creator/src/plugins/git/gitclient.cpp, line 3598
Cannot update Qt version information: /home/USER/Qt/6.3.1/gcc_64/bin/qmake cannot be run.

On version 8.0.0 (Qt 6.3.1 / GCC 10.3.1 20210422 / Red Hat 10.3.1-1) it changes to say:

Warning: Ignoring WAYLAND_DISPLAY on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
Cannot update Qt version information from /home/USER/Qt/6.3.1/gcc_64/bin/qmake: "/home/USER/Qt/6.3.1/gcc_64/bin/qmake" produced no output: ..

In Kits -> Qt Versions -> Auto-detected Qt

• qmake path: /home/USER/Qt/6.3.1/gcc_64/bin/qmake
• qmake does not exist or is not executable

qmake does exist and is executable, its output:

QMake version 3.1
Using Qt version 6.3.1 in /home/USER/Qt/6.3.1/gcc_64/lib

The only version of Qt Creator that still works is 5.0.3 using Qt 5.15.2 / GCC 7.3.1 20180303 / Red Hat 7.3.1-5

[cristian-adam]

Is there a bug report about this at http://bugreports.qt.io/ ?

[jarvis76]

@cristian-adam It has been reported here: https://bugreports.qt.io/browse/QTCREATORBUG-28067

[cristian-adam]

You can download Qt Creator 8.0.1 built for Qt5 https://download.qt.io/snapshots/qtcreator_qt5/8.0/8.0.1/241/

It worked for me with Rocky Linux 8.6 in a VirtualBox.

[cristian-adam]

As it turns out it's due to a bug in the 4.18 kernel that is used by Rocky LInux 8.6.

See QTBUG-101275 Unable to capture output from QProcess and Bug 2082719 - kernel-4.18.0-358.el8.x86_64 doing strange things to sddm on centos stream 8.

And apparently has been fixed in kernel-4.18.0-392.el8.

[jarvis76]

@cristian-adam Thanks, it works great