It breaks when creating packages, i.e. affects OBS package generation.
It fails (FTBFS) when running make distcheck:
libtool: error: 'lib/shinonome/libeasyrpg_player_la-gothic.lo' is not a valid libtool object
The offending line seems to be there since Player 0.2 (my bad):
EXTRA_DIST = builds lib Modules resources CMakeLists.txt src/platform
I guess the "lib" folder shouldn't be there.