I write new stuff in Python3, and what I do easily works on any Python3. I don't have Python2 code to maintain, but if I had I would seriously consider updatin

I write new stuff in Python3, and what I do easily works on any Python3. I don't have Python2 code to maintain, but if I had I would seriously consider updating it. Because I think the changes are reasonable for the most part. Dou you write your C code in GCC C? Intel C? Microsoft C? C89? C99? C11? What libraries and what versions do you use?