The Compact C Type Format in the GNU toolchain

I don't think they are really duplicates. BTF is describing the BPF type system: maps maps maps. CTF is describing the C type system: it can already handle floats, for instance, and things like 'restrict', and I am definitely going to add everything in GNU C, including things like vector and fixed-point types.

(And, honestly, I see no reason why we can't translate one into the other anyway. If BTF can be translated from DWARF, I'm sure I can write a CTF->BTF translator :) ).