c1_globals.hpp includes c1_globals_pd.hpp. c1_globals_pd.hpp includes the corresponding CPU_HEADER and OS_HEADER files. All of the c1_globals_<os>.hpp files are essentially identical and basically empty. (They just include globalDefinitions.hpp and macros.hpp, and provide nothing additional.)

This could be simplified by having c1_globals.hpp do the CPU_HEADER inclusion directly, and remove c1_globals_pd.hpp and all c1_globals_<os>.hpp files.

Even if there are some non-vacuous c1_globals_<os>.hpp files in the future, c1_globals_pd.hpp seems unwarranted; just add the OS_HEADER include directly in c1_globals.hpp. The c1_globals_pd.hpp files really don't seem worth the extra indirection.

Similarly for c2_globals.hpp &etc.