QGIS » QGIS Application

I'm using the instructions of https://github.com/qgis/QGIS/blob/master/INSTALL#L186 to compile QGIS 3 in Ubuntu Artful, but in process of "make -j8" (In my case) I'm getting the error:

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<pre>
Scanning dependencies of target translations [ 98%] Building CXX object src/plugins/grass/7/CMakeFiles/grassplugin7.dir/__/qtermwidget/moc_TerminalDisplay.cpp.o
[ 96%] Generating ../output/i18n/qgis_ar.qm 98%] Building CXX object src/plugins/grass/7/CMakeFiles/grassplugin7.dir/__/qtermwidget/moc_Vt102Emulation.cpp.o
lrelease: could not find a Qt installation of '' [ 98%] Building CXX object src/plugins/grass/7/CMakeFiles/grassplugin7.dir/__/qtermwidget/moc_kprocess.cpp.o
i18n/CMakeFiles/translations.dir/build.make:97: [ 98%] Building CXX object src/plugins/grass/7/CMakeFiles/grassplugin7.dir/__/qtermwidget/moc_kptydevice.cpp.o
[ 98%] Building CXX object src/plugins/grass/7/CMakeFiles/grassplugin7.dir/__/qtermwidget/moc_kptyprocess.cpp.o
[ 98%] Building CXX object src/plugins/grass/7/CMakeFiles/grassplugin7.dir/__/qtermwidget/moc_qtermwidget.cpp.o
[ 98%] Building CXX object src/plugins/grass/7/CMakeFiles/grassplugin7.dir/qrc_qgsgrass_plugin.cpp.o
[ 98%] Linking CXX shared module ../../../../output/lib/qgis/plugins/libgrassplugin7.so
[ 98%] Built target grassplugin7
Makefile:162: recipe for target 'output/i18n/qgis_ar.qm' &#39;all&#39; failed
make[2]: make: *** [output/i18n/qgis_ar.qm] [all] Error 2
</pre>