QApplication: No such file or directory

[WhyNotHugo]

$ make
g++ -c -pipe -std=c++11 -g -D_REENTRANT -Wall -W -fPIC -DQT_GUI_LIB -DQT_CORE_LIB -I. -isystem /usr/include/qt -isystem /usr/include/qt/QtGui -isystem /usr/include/qt/QtCore -I. -I/usr/lib/qt/mkspecs/linux-g++ -o main.o main.cpp
main.cpp:2:24: fatal error: QApplication: No such file or directory
compilation terminated.
Makefile:419: recipe for target 'main.o' failed
make: *** [main.o] Error 1

Archlinux, amd64. qt 5.4.1 and 4.8.7 installed.

[WhyNotHugo]

Oh, right after posting the above I realized I should try this:

qmake-qt4
make

And it works. Maybe a README should clarify this. :)