Try out gcc 6

[pervazea]

Assess if Peloton compiles and / or what changes are needed to get it to compile

[crd477]

For what it's worth, it used to work just fine under Debian Stretch which uses gcc 6.3 as the default (i.e., apt-get install gcc). This was before a lot of the integration of TF and other things though so I don't know if it would still work. At the very least, the corresponding packages.sh section would need updating.

[mbutrovich]

Default on Ubuntu 18.04 is GCC 7 and that worked for me when I was testing a couple of weeks ago.

[pmenon]

Seems to compile okay if we update to C++14, too (default on GCC6 and GCC7).

[mbutrovich]

C++14 is good on (Apple) Clang too. Sounds like we have a decent list of toolchain updates to discuss at the end of summer (LLVM, C++14, GCC, clang-format, etc.).