"fringe platforms which can't even run a Rust compiler"

> Yes, but that still doesn't magically collapse all the typedefs. With just socket.h that produces 500 lines of C, that a C compiler and scripts shared by *all* ports would much better grok than doing seds by hand.

Aha, thank you for giving me another use case for CTF! The upcoming CTF format v4 work will include an objdump option that emits a collection of C header files given a .ctf section. They won't be the same as the inputs, of course (no comments, for starters, and with the default linker options you'll get one big header for non-ambiguous types and then small headers #including the big one for all the ambiguously-defined ones), but it'll be better than nothing -- but until now I didn't have an answer for why this would ever be better than using the original .h files. Now I have one: transformations on the headers to help people doing work like this. (A transformation that collapses away all typedefs, leaving everything textually defined in terms of the base types, and leaving the typedefs around but with no actual users, should be trivial to implement. It's probably a bad idea to *use* those headers, but for human analysis for FFIs it's probably likely to be useful.)