After creating a new project and hitting “Generate the code” button (or menu option), the application will write the Makefile file. The structure and the content of the file is heavily inspired from CubeMX Makefile template, with little addition from my part.

The debug, optimization options, floating point options that you set the moment you create the project or when you edit the project settings, the toolchain folder, all are illustrated in the Makefile (things that are not automated or completely missing from the CubeMX Makefile generation).

But not yet tested, and it might very well not work at all …
Anyway, I moved onto main.h header generation which is not yet complete.
See the repository (in the right panel).