Installing macvim 7.4 already supports clipboard
gvim --version | grep clipboard
+clipboard +iconv +path_extra +transparency
+eval +mouse_dec +startuptime -xterm_clipboard
But after setting up
set clipboard=unnamed
No effect?
http://vim.wikia.com/wiki/Mac_OS_X_clipboard_sharing
There will be problems when opening in tmux
https://hynek.me/articles/macvim-and-the-clipboard/