GCC 7 default update planned for early August

[Matthias Klose]

Hi,

it's this time of the year where you go to your vacation, and look at a new
shiny new GCC version in the archive when you come back.  Well, not exactly ...

I'm planning to change the default on Aug 03/04, and then working to get things
migrated and buildable again, including two transitions for GCC runtime
libraries.  Fixing things pro-actively is appreciated.  If there are questions,
please use the #ubuntu-devel irc channel.  Resources for the GCC 7 update are:

Results of a test rebuild using GCC 7:

  http://qa.ubuntuwire.org/ftbfs/rebuilds/test-rebuild-20170706-gcc7-artful.html

The ubuntu-toolchain-r/test PPA has the updated defaults packages.

Distro specific informations (and bugs filed for Debian only):

  https://wiki.debian.org/GCC7

Upstream documentation for porting:

  https://gcc.gnu.org/gcc-7/porting_to.html

Thanks for your support for this update!

  Matthias