Why does Qt use its own make tool, qmake?

Question

I just started using Qt and noticed that it uses its own make tool, qmake.

• Why does Qt use its own make tool?
• Is there something special that prevents

Answer 1

To support its signal/slot system Qt relies on a special preprocessor and compiler that generates intermediate objects that do much of the processing. They refer to this as the Meta-Object Compiler or MOC.

See Qt 5 Documentation: Using the Meta-Object Compiler for details.

The MOC (along with a couple of other intermediate tools) works in conjunction with qmake; a build automation tool which produces Makefiles in your native format (VC++, g++, etc.) that build the intermediate files generated by the MOC as well as all of your source files into the final executable.