Building for android from source; undefined reference to Win32MakefileGenerator

sierdzio

You forgot to tell Qt that it should cross-compile: please add the -xplatform android-g++ flag to your configure call.

Wiru

Wish that would help, I tried with and without it (randomly trying to see what's wrong) and posted the line where I didn't include the -xplatform but even with it I get the same error.
I don't know if it would help to change some parameters maybe?

Previously I build the same source for linux without issues, but then again it's different for android.

sierdzio

@Wiru said in Building for android from source; undefined reference to Win32MakefileGenerator:

Previously I build the same source for linux without issues, but then again it's different for android.

Make sure your build dir is clean, then.

Also, what is -android-ndk-host linux-x86_64 doing there? Perhaps follow the Windows instructions since your host is Windows https://wiki.qt.io/Building_qt-android_on_windows . Not sure if they work, I've never tried building Qt for Android on Windows.

Wiru

The thing is that the host is linux, that's why the Win32MakefileGenerator is even more confusing. I deleted all the modified flies, at least all that git said were different. I'll try to clone again just in case some files got ignored and didn't show up in git.

Wiru

Ok that was one reason, apparently some stuff stays from old builds and it's not shown in git.
Now the only issue is I get the ERROR: Unknown command line option -skip, if I understand right it should be used to not build unsupported modules.
But it does say

Creating qmake...
.Done.
ERROR: Unknown command line option -skip

So not sure if that's something that can be ignored.

sierdzio

@Wiru said in Building for android from source; undefined reference to Win32MakefileGenerator:

The thing is that the host is linux, that's why the Win32MakefileGenerator is even more confusing. I deleted all the modified flies, at least all that git said were different. I'll try to clone again just in case some files got ignored and didn't show up in git.

Ah, ok sorry I got confused :-)

If you use git and clean it (git clean -dxf) make sure the repo is initialized.

Best way to safely compile Qt is to do an out of source build:

git clone ...
cd repo
perl init-repository
cd ..
mkdir build 
cd build
../repo/configure ...

Easier yet - use a tarball from qt.io archive. It's a faster download, no need to init-repository, in general just less hassle.

sierdzio

Here is a script I use to compile Qt on Android, maybe it will help you. Host is Kubuntu 18.10 in this case.

export QTVER=5.11.1
    wget http://download.qt.io/official_releases/qt/5.11/$QTVER/single/qt-everywhere-src-$QTVER.tar.xz
    tar -xaf qt-everywhere-src-$QTVER.tar.xz
    mv qt-everywhere-src-$QTVER $QTVER-src
    mkdir qtbuild
    cd qtbuild
    # Check if this path is correct
    export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-amd64
    export ANDROID_NDK_ROOT=/path/to/android/ndk-r10e
    ../$QTVER-src/configure -release -xplatform android-g++ --disable-rpath -nomake tests -nomake examples -android-ndk-host linux-x86_64 -android-toolchain-version 4.9 -android-ndk $ANDROID_NDK_ROOT -android-sdk /path/to/android/sdk -no-warnings-are-errors -opensource -confirm-license -prefix ../$QTVER-android -skip qttranslations -skip qtserialport -skip qtserialbus -skip qtscxml -skip qtscript -skip qtcharts -skip qt3d -skip qtdatavis3d -skip qtcanvas3d -skip qtgamepad -skip qtvirtualkeyboard -skip qtwayland -skip qtwebengine -skip qtwebchannel -skip qtwebsockets -android-arch armeabi-v7a
    time make -j `nproc`
    make install

You may want to experiment with some OpenSSL flags, too, but I've left them out to make it easier.

sierdzio

@Wiru said in Building for android from source; undefined reference to Win32MakefileGenerator:

Ok that was one reason, apparently some stuff stays from old builds and it's not shown in git.
Now the only issue is I get the ERROR: Unknown command line option -skip, if I understand right it should be used to not build unsupported modules.
But it does say
Creating qmake...
.Done.
ERROR: Unknown command line option -skip
So not sure if that's something that can be ignored.

Nope. Your build dir or environment is seriously wrong if it fails to recognise -skip.

Wiru

Thanks for the help, I'll play around with settings.
First I'll try to download the zip because using perl init-repository just ends up with Can't open perl script "init-repository" no such file or directory, and first I do cd qtbase, so who knows what's not working correctly.

Wiru

Ok I simply have no luck.
I downloaded the tar 5 times, and every time
wget http://download.qt.io/official_releases/qt/5.11/5.11.1/single/qt-everywhere-src-5.11.1.tar.xz

~/source_qt $ tar -xaf qt-everywhere-src-5.11.1.tar.xz 
xz: (stdin): Compressed data is corrupt
tar: Unexpected EOF in archive
tar: Unexpected EOF in archive
tar: Error is not recoverable: exiting now

I'll continue trying with the git source... :S

SGaist

Hi,

The .zip archive is for Windows.
The .tar.xz archive is for Linux.

Completely unrelated to the target you want to build for, it's a question of line ending type.

Wiru

It is for linux, I tried one more time and now it was ok. Only thing is that's not what I need, since I can't edit the files like this, so I still have to use the git version.

Wiru

The mystery about -skip not found is simply because I was building the wrong repo the whole time qtbase instead of qt5, that's also why the perl init-repository didn't work...
I feel a bit stupid, but now I know something new.
Thank you all for the help.

sierdzio

No worries :-) Building Qt is a complex thing, I guess we all understand it and went through similar hurdles at some point in the past ;-) Happy coding!