Should I change -Di386 entries in the makefiles?

[prickle]

I've figured it out enough for myself to understand at this point with the help of some Google Fu.

The -Di386 needs to stay as that's the basic architecture. The -march=xxxxxxx is the optimization instruction set to compile into the binary during compile. Essentially, Intel and AMD 64 bit processors are x86 processors with their individual 64 bit optimizations...

As for your question with some makefiles with and without the -D flag, i believe the ones without are being called upon by other makefile(s) and inherit the -D flags from those files.