Emscripten ABI compatibility checks for side modules?

There has been discussion with the CPython folks about trying to add `wasm32-emscripten` wheels to PyPI. For this, we would like to have some way to decide which wheels are compatible with which main modules. Looking around, I see there used to be `EMSCRIPTEN_ABI_MAJOR` and `EMSCRIPTEN_ABI_MINOR` but they were removed.

Suppose we compile a main module and a side module at separate times using possibly different versions of Emscripten. Is there any way to check whether they are compatible? Could such a feature be added? What will happen at load time if they are not compatible?