I just tried to test on the Mac (commenting out the GUI building part of the code), and I get the following error:
[ 9%] Building CXX object CMakeFiles/btc.dir/irc.cpp.o
/Users/alkor/Desktop/Dev/bitcoin/irc.cpp: In function ‘bool Send(SOCKET, const char*)’:
/Users/alkor/Desktop/Dev/bitcoin/irc.cpp:61: error: ‘MSG_NOSIGNAL’ was not declared in this scope
make[2]: *** [CMakeFiles/btc.dir/irc.cpp.o] Error 1
make[1]: *** [CMakeFiles/btc.dir/all] Error 2
make: *** [all] Error 2