You can always run configure -help and inspect the options, so an external file is not that important. The problem is you have to think about handling those options afterwards The simplest solution is to just... ignore new switches or give a list of options to enable/modify them at the end of the configuration process and I think it's a good solution for a start.
I'll think about it. I will choose the solution which seems most fit on a long term.
I think I will start this project this week, but I don't know when it's gonna be ready. Hope it won't take more than two weeks.
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