Why do we need _fake_defines.h? about pycparser

[eliben]

I see your point. However, you only have a single use in your mind - source transformation. Keep in mind that source transformation was never an explicit goal of pycparser; pycparser creates an AST which loses so much syntactic information that accurate source transformation is infeasible anyhow. In the past, other uses of pycparser (like a frontend for a very basic C compiler) found the fake defines useful.

Reconciling very different uses of a tool is difficult. But the fake headers are just optional utils, not really a core part of pycparser. If someone has special needs, they can serve as a template for more comprehensive fake headers.