Cpp-library plugin produces .obj / .lib file whereas it uses mingw64

Hello,

As stated in the title, I cannot find the way to specify that I want .o / .a files instead of .obj / .lib. I’m on Windows 10 and I use msys2 / mingw64.

Here is my build script : https://pastebin.com/jPAVFpwj

Thanks for your answers.