QT5 won't compile.

I am trying to create a backup copy of QT5 for Slackware 14.2 (64-bit), but after about six hours worth of compiling, the procrss seems to "hang" at this point:Code:make[4]: Leaving directory '/tmp/SBo/qt-everywhere-src-5.12.8/qtwebengine/src/core/api'
( test -e Makefile.core_module || /tmp/SBo/qt-everywhere-src-5.12.8/qtbase/bin/qmake -o Makefile.core_module /tmp/SBo/qt-everywhere-src-5.12.8/qtwebengine/src/core/core_module.pro ) && make -f Makefile.core_module
make[4]: Entering directory '/tmp/SBo/qt-everywhere-src-5.12.8/qtwebengine/src/core'
perl /tmp/SBo/qt-everywhere-src-5.12.8/qtbase/mkspecs/features/data/unix/findclasslist.pl < QtWebEngineCore.version.in > QtWebEngineCore.version
rm -f libQt5WebEngineCore.so.5.12.8 libQt5WebEngineCore.so libQt5WebEngineCore.so.5 libQt5WebEngineCore.so.5.12
g++ @/tmp/SBo/qt-everywhere-src-5.12.8/qtwebengine/src/core/release/QtWebEngineCore_o.rsp -Wl,--start-group @/tmp/SBo/qt-everywhere-src-5.12.8/qtwebengine/src/core/release/QtWebEngineCore_a.rsp -Wl,--end-group -Wl,-z,noexecstack -Wl,--fatal-warnings -Wl,--build-id=sha1 -fPIC -Wl,-z,now -Wl,-z,relro -Wl,-z,defs -m64 -Wl,-O2 -Wl,--gc-sections -rdynamic -Wl,-O1 -L/usr/lib64 -Wl,--enable-new-dtags -Wl,-whole-archive -lqtwebenginecoreapi -Wl,-no-whole-archive -Wl,--no-undefined -Wl,--version-script,QtWebEngineCore.version -Wl,-O1 -L/usr/lib64 -Wl,--enable-new-dtags -shared -Wl,-Bsymbolic-functions -Wl,-soname,libQt5WebEngineCore.so.5 -o libQt5WebEngineCore.so.5.12.8 /tmp/SBo/qt-everywhere-src-5.12.8/qtdeclarative/lib/libQt5Quick.so /tmp/SBo/qt-everywhere-src-5.12.8/qtbase/lib/libQt5Gui.so /tmp/SBo/qt-everywhere-src-5.12.8/qtwebchannel/lib/libQt5WebChannel.so /tmp/SBo/qt-everywhere-src-5.12.8/qtdeclarative/lib/libQt5Qml.so /tmp/SBo/qt-everywhere-src-5.12.8/qtbase/lib/libQt5Network.so /tmp/SBo/qt-everywhere-src-5.12.8/qtlocation/lib/libQt5Positioning.so /tmp/SBo/qt-everywhere-src-5.12.8/qtbase/lib/libQt5Core.so -lpthread -lpthread -ldl -lrt -lnss3 -lsmime3 -lsoftokn3 -lnssutil3 -lplds4 -lplc4 -lnspr4 -lsqlite3 -lexpat -levent -lresolv -lz -lpng16 -lwebpmux -lwebpdemux -lwebp -lfreetype -ljpeg -lfontconfig -lX11 -lX11-xcb -lxcb -lXcomposite -lXcursor -lXdamage -lXext -lXfixes -lXi -lXrender -lXtst -lXss -lpci -lasound -lm -lopus -ldbus-1 -lminizip -llcms2 -L/tmp/SBo/qt-everywhere-src-5.12.8/qtwebengine/src/core/api/release /usr/lib64/libGL.so