Ubuntu 15.10, the Wily Werewolf, will closely follow Debian in its GCC 5 compiler upgrade and libstdc++6 ABI updates. They hope to have everything settled for Ubuntu 15.10 to avoid any big tool-chain changes during the Ubuntu 16.04 LTS cycle...
July 7, 2015
Ubuntu 15.10 To Follow Debian In Its March To GCC 5
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