I’ve had a number of people ask about this… The current state of the universal / combined MAME+MESS builds is simple.
The patch for the universal build target (posted 14th Feb 2012) still works as expected. This makes no changes to the existing source files, and simply adds a new folder called ‘uni’ containing details of the build target.
All that’s needed is for you to check out the current MESS sources from their public SVN or the GIT linked on the left and apply the patch, then change the target to ‘uni’ in the makefile ( or compile with make TARGET=uni )
There are no known current conflicts & everything should work just as well as it does in the individual builds. All validity checks pass. The compiler / linker still doesn’t report conflicting class names, but hopefully those have all been resolved manually.
Still no word on this going in the tree officially, but the work is all done and has been for a while. As stated previously the only thing I’d do is rebrand the target as ‘une’ the “UNiveral Emulator”
For whatever reason the megatech.xml & stv.xml (used for loading of those systems via software lists) are missing from the MESS distributions despite being in a shared folder, so you might want to copy those over from MAME if you plan on using the softlists for them, however the standard ‘internal lists’ still work fine in those cases as long as you don’t want multi-slot support.
I’ll probably post binaries sometime around the next full release, but I’d like to see the remaining CHD issues (random hangs) ironed out first, the ECC CD compression patch I sent Aaron applied in a suitable / clean way, and the lists all updated to use CHDv5 hashs where appropriate.