I would like to use include files in "Compiler explorer" and tried this with the help from this question.
Include external header file for C on Compiler Explorer
But I get allays an fatal error: 'F0_MemMap.h' file not found.
This is my project:
https://godbolt.org/z/qqervK1en
Looks like you've got a "compiler window" that's linked to only that one C++ file. That file will be compiled on its own.
Sorry it's not clearer, but if you close the compiler window, then click "Add New..." on the "Tree #1" (cmake) window, you'll get this: https://godbolt.org/z/4Wv4WhG5E
Here you'll see it's now running the whole project as a CMake build (not just a single file build).
The file inclusions are then found OK; but there are still issues with the build itself (which I haven't tried to look in to).
Hope that helps with your original question!