qtmqtt make error on linux: "qmqttglobal.h: No such file or directory"

udayraj123

Steps to reproduce my problem:

Download zip from https://github.com/qt/qtmqtt
cd into the folder and run qmake; and then make;
Following error is produced:
qmqttclient.h:33:32: fatal error: QtMqtt/qmqttglobal.h: No such file or directory

Update: tried with qmake -r as well, but no effect.
I have also seen this link: https://forum.qt.io/topic/80659/how-to-add-library-qmqtt-h-in-qmqtt-client-for-windows/ but it is a bit confusing and I am still stuck. How to compile this library so that I can use mqtt in Qt?

Thanks,
Udayraj

Egn1n3

What happens if you do: qmake -r

udayraj123

@Egn1n3 The qmake -r command produces output as follows -

Reading /home/test/Documents/qtmqtt-5.11/src/src.pro [/home/test/Documents/qtmqtt-5.11/build/src]
 Reading /home/test/Documents/qtmqtt-5.11/src/mqtt/mqtt.pro [/home/test/Documents/qtmqtt-5.11/build/src/mqtt]
Reading /home/test/Documents/qtmqtt-5.11/examples/examples.pro [/home/test/Documents/qtmqtt-5.11/build/examples]
 Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/mqtt.pro [/home/test/Documents/qtmqtt-5.11/build/examples/mqtt]
  Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/simpleclient/simpleclient.pro [/home/test/Documents/qtmqtt-5.11/build/examples/mqtt/simpleclient]
  Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/subscriptions/subscriptions.pro [/home/test/Documents/qtmqtt-5.11/build/examples/mqtt/subscriptions]
Reading /home/test/Documents/qtmqtt-5.11/tests/tests.pro [/home/test/Documents/qtmqtt-5.11/build/tests]
 Reading /home/test/Documents/qtmqtt-5.11/tests/auto/auto.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto]
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/cmake/cmake.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto/cmake]
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/conformance/conformance.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto/conformance]
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqttcontrolpacket/qmqttcontrolpacket.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto/qmqttcontrolpacket]
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqttclient/qmqttclient.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto/qmqttclient]
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqttsubscription/qmqttsubscription.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto/qmqttsubscription]
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqtttopicname/qmqtttopicname.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto/qmqtttopicname]
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqtttopicfilter/qmqtttopicfilter.pro [/home/test/Documents/qtmqtt-5.11/build/tests/auto/qmqtttopicfilter]
 Reading /home/test/Documents/qtmqtt-5.11/tests/benchmarks/benchmarks.pro [/home/test/Documents/qtmqtt-5.11/build/tests/benchmarks]
  Reading /home/test/Documents/qtmqtt-5.11/tests/benchmarks/qmqttclient/qmqttclient.pro [/home/test/Documents/qtmqtt-5.11/build/tests/benchmarks/qmqttclient]

But then on doing make again, same error comes up: QtMqtt/qmqttglobal.h: No such file or directory

udayraj123

Okay, seems like cmake is not installed on my system. I'm installing it and running again now.
Update: Still exact same error. Updated the qmake -r output above.

SGaist

Hi,

Are you sure you are using the qmake executable of your Qt 5.11 ?

Sifu

@udayraj123 said in qmqtt make error on linux: "qmqttglobal.h: No such file or directory":

QtMqtt/

Edit the Makefile and add the option "-I/path-to-the-QtMqtt-header file"

jsulm

@Sifu Editing the Makefile isn't a good idea as it is auto-generated and will be overwritten next time qmake is executed.

udayraj123

@SGaist Just checked, it was using from /usr/bin
which qmake
/usr/bin/qmake

find ~/ -type f -executable -name 'qmake'

/home/test/Qt/5.11.0/android_x86/bin/qmake
/home/test/Qt/5.11.0/gcc_64/bin/qmake
/home/test/Qt/5.11.0/android_armv7/bin/qmake

So trying the second one now-

/home/test/Qt/5.11.0/gcc_64/bin/qmake -version
QMake version 3.1
Using Qt version 5.11.0 in /home/test/Qt/5.11.0/gcc_64/lib

cd qtmqtt-5.11
On using this qt I am getting a different error:

/home/test/Qt/5.11.0/gcc_64/bin/qmake -r

Info: creating stash file /home/test/Documents/qtmqtt-5.11/.qmake.stash
Info: creating cache file /home/test/Documents/qtmqtt-5.11/.qmake.cache
Reading /home/test/Documents/qtmqtt-5.11/src/src.pro
 Reading /home/test/Documents/qtmqtt-5.11/src/mqtt/mqtt.pro
Reading /home/test/Documents/qtmqtt-5.11/examples/examples.pro
 Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/mqtt.pro
Project ERROR: You cannot build examples inside the Qt source tree, except as part of a proper Qt build.

Update: On running it again, it worked!
/home/test/Qt/5.11.0/gcc_64/bin/qmake -r

Reading /home/test/Documents/qtmqtt-5.11/src/src.pro
 Reading /home/test/Documents/qtmqtt-5.11/src/mqtt/mqtt.pro
Reading /home/test/Documents/qtmqtt-5.11/examples/examples.pro
 Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/mqtt.pro
  Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/simpleclient/simpleclient.pro
  Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/subscriptions/subscriptions.pro
  Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/quicksubscription/quicksubscription.pro
  Reading /home/test/Documents/qtmqtt-5.11/examples/mqtt/websocketsubscription/websocketsubscription.pro
Reading /home/test/Documents/qtmqtt-5.11/tests/tests.pro
 Reading /home/test/Documents/qtmqtt-5.11/tests/auto/auto.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/cmake/cmake.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/conformance/conformance.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqttcontrolpacket/qmqttcontrolpacket.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqttclient/qmqttclient.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqttsubscription/qmqttsubscription.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqtttopicname/qmqtttopicname.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/auto/qmqtttopicfilter/qmqtttopicfilter.pro
 Reading /home/test/Documents/qtmqtt-5.11/tests/benchmarks/benchmarks.pro
  Reading /home/test/Documents/qtmqtt-5.11/tests/benchmarks/qmqttclient/qmqttclient.pro

Now make and sudo make install has finished building.
The directory /usr/lib/x86_64-linux-gnu/qtmqtt-5.11/ is now created
Will test with sample app now.

udayraj123

For changing the qmake, I replaced /usr/bin/qmake with new one using following command-

sudo mv /usr/bin/qmake /usr/bin/qmake.old
sudo ln -s /home/test/Qt/5.11.0/gcc_64/bin/qmake /usr/bin/qmake
qmake -version
 QMake version 3.1
 Using Qt version 5.11.0 in /home/test/Qt/5.11.0/gcc_64/lib

Now when I opened the qtmqtt-5.11 folder in qt creator, it first gave this warning:

Project ERROR: Module does not define version.
Error while parsing file /home/test/Documents/qtmqtt-5.11/src/mqtt/mqtt.pro. Giving up.
Project MESSAGE: This project is using private headers and will therefore be tied to this specific Qt module build version.
Project MESSAGE: Running this project against other versions of the Qt modules may crash at any arbitrary point.
Project MESSAGE: This is not a bug, but a result of using Qt internals. You have been warned!

Still proceeded to "Build all" and it worked. But now on doing "Run" -
I get this error:
In file included from /home/test/Documents/qtmqtt-5.11/examples/mqtt/simpleclient/main.cpp:51:0:
/home/test/Documents/qtmqtt-5.11/examples/mqtt/simpleclient/mainwindow.h:55:23: fatal error: QMqttClient: No such file or directory

SGaist

You should do out of source builds. This keeps the source clean and allows you to nuke the build folder if something goes wrong.

Do not change your distribution provided qmake. Use the full path to the version you want to use. You can be sure that you are going to hit a wall once you update Qt to a newer version.

udayraj123

Actually I tried the same procedure on a different PC, but it is not working on it.
It is showing the QtMqtt/qmqttglobal.h not found error. I think it bypassed it in mine because yesterday I had tried building by manually adding a QtMqtt/ directory inside ~/Qt/5.11.0/gcc_64/include/

ls ~/Qt/5.11.0/gcc_64/include/QtMqtt/

qmqttclient.h        qmqttconnection_p.h     qmqttglobal.h     qmqttmessage.h         qmqttsubscription.h    qmqtttopicfilter.cpp  qmqtttopicname.cpp
QMqttClient      qmqttclient_p.h      qmqttcontrolpacket.cpp  QMqttMessage      QMqttSubscription      qmqttsubscription_p.h  qmqtttopicfilter.h    qmqtttopicname.h
qmqttclient.cpp  qmqttconnection.cpp  qmqttcontrolpacket_p.h  qmqttmessage.cpp  qmqttsubscription.cpp  QMqttTopicFilter       QMqttTopicName        QtMqttDepends

echo ~/Qt/5.11.0/gcc_64/include/QtCore/5.11.0/QtCore/private/qmqtt*

/home/test/Qt/5.11.0/gcc_64/include/QtCore/5.11.0/QtCore/private/qmqttclient_p.h
(omitted) /private/qmqttconnection_p.h
(omitted) /private/qmqttcontrolpacket_p.h
(omitted) /private/qmqttsubscription_p.h

udayraj123

@SGaist Yes, I should use the full path. But If I am using it just for testing this one project right now, then I guess it should be fine(?)
About build folder - okay I'll do it from next time. Currently to restart the build I was deleting qtmqtt folder and extracting the zip again.

Also, how can I get this 1 reputation to be able to reply faster

SGaist

You are invoking Murphy's Law.

I'd recommend doing that now so you ensure that you have a full correct build also when calling make install.

To get a +1 somebody has to upvote one of your question or answer.

Sifu

@udayraj123 said in qmqtt make error on linux: "qmqttglobal.h: No such file or directory":

QtMqtt

Hi,
The reason behind the problem is the QtMqtt header files were not inside the default system include folders, when you run the make it will only take the external header files from the system include directories like /usr/include . /usr/share/include . etc,. . Here you installed the QtMqtt inside your home which is not a regular location of included. You are not telling the make that you need to include the header from a folder inside your home.

Solution 1 : You may set the INCLUDE_PATH in your environment variable in shell , or, update the build configuration https://doc-snapshots.qt.io/qtcreator-4.0/creator-build-settings.html

Soluton 2 : Install QtMqtt as root user with prefix=/usr , this may be easy

udayraj123

Thanks for your solutions, I'll try them, but I have some doubts-

QtMqtt header files were not inside the default system include folders...

Shouldn't this be a problem for all then? Is it building on your system without having to do the suggested change?

Here you installed the QtMqtt inside your home which is not a regular location of included

What location would you suggest for installing it?

Install QtMqtt as root user with prefix=/usr , this may be easy

I did not get the 'prefix=/usr' part.

SGaist

@udayraj123 said in qtmqtt make error on linux: "qmqttglobal.h: No such file or directory":

Thanks for your solutions, I'll try them, but I have some doubts-

QtMqtt header files were not inside the default system include folders...

Shouldn't this be a problem for all then? Is it building on your system without having to do the suggested change?

No, because you're not doing a system install. These headers should be found in the Qt installation you used to build the module after you called make install.

Here you installed the QtMqtt inside your home which is not a regular location of included

What location would you suggest for installing it?

Using the correct qmake executable, it should install the module in the correct folders.

Install QtMqtt as root user with prefix=/usr , this may be easy

I did not get the 'prefix=/usr' part.

When doing a full Qt build, you can configure where the installation should happen. You are not concerned by this.

Pablo J. Rogina

@udayraj123 said in qtmqtt make error on linux: "qmqttglobal.h: No such file or directory":

Download zip from https://github.com/qt/qtmqtt

I can confirm that using the .zip download from such location gave me same errors as you mention (I'm using Lubuntu 18.04 / Qt 5.11)

However cloning https://code.qt.io/qt/qtmqtt.git and doing:

qmake -r
qmake
make
sudo make install

led to QtMQTT module built Ok and installed along other existing modules in my Qt installation so later on you could use the module in any application (i.e. provided examples or your own).