Qmake, How to link with different architecture libraries?

I'm programming an c++ application in qtcreator, which use 64-bit libraries. But I also need to use some features that are in 32-bit libraries and these have not 64-bit versions. Is it possible to use links to libraries of 32 and 64 bits in the same qmake project?

No C++ compiler that I am aware of would allow this.

You could split your application into two processes:
- one linking the 64bit libraries
- one linking the 32bit libraries

and one starting the other as a child process.

Cheers,
_