It regressed by 0.4.12-dev-1064-g 09c4d0a74b
when we tried to mute compiler warnings in the GCC Release configuration
for all modules, that do contain .y files.
In master we switched to use flex+bison to process those files at build-time
in 0.4.15-dev-2277-g 28dadda8be and at the same
time reverted the guilty rev.
In the backport to the old releases we do only revert, but do not introduce
flex+bison. This will reintroduce the warnings in GCC Release configuration.
