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I am not inclined to roll back the code we do have and write a lot of new code in C. Yes, it’s more portable, easier and faster to build, etc. It’s also far more error prone and lacking in basic library facilities that modern C++ has available. That said, the nature of that C++ code needs to change radically, simplifying and modernizing it, dropping reducing the use of templates wherever possible, and sticking to the standard library and only limited usage of Boost where essential.
The obvious target would be C++11, but C++14 is supported on all of the “current” platforms we support (granted, a very small set) and appears to be supported on all non-EOL versions of Debian/Ubuntu. The main outliers for C++14 support are RHEL 7 (and similar) and Suse 12, neither of which are actively supported, though we do build packages for CentOS 7 and Amazon Linux 2. The former addresses RHEL 7, which is extremely widely adopted (and will be long past its EOL date).
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