Each libretro profile records version_basis and core_version is read
there at its pin. snes9x states 1.63 in snes9x.h, nestopia 2.0.0, mgba
0.11.0, vice 3.10, atari800's libretro tree 7.0.0. Cores whose build
takes its version from git carry the nearest tag in describe form
(flycast v2.7-90-ge88b0ce, ppsspp, duckstation, gearcoleco), placeholders
copied from .info files (Git, SVN) are replaced by the code's statement,
and a code that states none is null with kind none.
100 emulator names the two platforms run had no profile, so their packs carried nothing for them. Each was read from the platform's own launcher or scriptmodule: the same program as an existing profile takes the name in cores:, a different build gets its own profile read from that version, a launcher or self-contained game goes to remove_cores, and the rest are new profiles written from their source or shipped binary. The files they need that the collection lacked are collected from the upstream distributions. Bungie and splitwolf trees are read by path and stay out of dedup.
Abdessamad Derraz