So you were linking against prebuilt libraries, and you had third party headers for those libraries that were doing some constexpr stuff that was breaking linki

So you were linking against prebuilt libraries, and you had third party headers for those libraries that were doing some constexpr stuff that was breaking linking because the prebuilts no longer matched the headers? In C++ if you aren’t able to build your entire stack of dependencies from source you are gonna have a bad time like this at some point. Any prebuilt libraries you depend on better be pure C, headers included.