tutorials/alarms not compiling

g++ -c -pipe -O2 -Wall -Wextra -D_REENTRANT -fPIC -DQT_NO_DEBUG -DQT_QUICK_LIB -DQT_GUI_LIB -DQT_QMLMODELS_LIB -DQT_QML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -I. -I../../../../5.15.15/gcc_64/include -I../../../../5.15.15/gcc_64/include/QtQuick -I../../../../5.15.15/gcc_64/include/QtGui -I../../../../5.15.15/gcc_64/include/QtQmlModels -I../../../../5.15.15/gcc_64/include/QtQml -I../../../../5.15.15/gcc_64/include/QtNetwork -I../../../../5.15.15/gcc_64/include/QtCore -I. -I/usr/include/libdrm -I../../../../5.15.15/gcc_64/mkspecs/linux-g++ -o main.o main.cpp
main.cpp: In function ‘int main(int, char**)’:
main.cpp:60:20: error: unable to find string literal operator ‘operator""_qs’ with ‘const char16_t [21]’, ‘long unsigned int’ arguments
   60 |     const QUrl url(u"qrc:/alarms/main.qml"_qs);
      |                    ^~~~~~~~~~~~~~~~~~~~~~~~~~
make: *** [Makefile:910: main.o] Error 1