Retroarch: MAME 2015 core not working

[Cibomatto2002]

MAME 2015 core not working it goes back to the RetroArch screen. games tester in Romcenter it shows there good copies. Also the MAME UI32 0.159 Emulator will run them. Is this the right Emulator to use with MAME 2015?

[hizzlekizzle]

This issue should probably be opened at the core repo, since it's (probably) out of the frontend's control:
https://github.com/libretro/mame2015-libretro

The description there says v0.160-ish, which means most v0.159 ROMs should work, but if they don't, what's the error it's giving in the logs? You can include that information when you open the new issue at the core tracker.

[Cibomatto2002]

I got it working I had to disable rewind.

[i30817]

Cores which don't support rewind (or other frontend features) should really advertise it in the API to prevent problems like this.

Or do they and the core is simply lying because 'part of' mame can use rewind?

[hizzlekizzle]

Rewind (and other RetroArch-specific goodies, like shaders, remaps, runahead, etc.) isn't part of the API, so the cores can't and shouldn't directly know anything about it (and therefore shouldn't announce compatibility with it). However, I completely agree with your sentiment, and to this end I've started (slowly) adding frontend-agnostic descriptors for some of these things in the core info files, which could theoretically be used to automatically disable incompatible features: https://github.com/libretro/libretro-super/blob/master/dist/info/bsnes_libretro.info#L77