clang++ version restricton

[gunjannandy]

Problem

If we specify clang++ verison 8 in Makefile.common like this:

/usr/bin/clang++-8

It won't work in clang++-9 though version 9 is supported.
But clang versions below 8 doesn't support aggregate expression. See below error:

dnnCompiler/include/operators/GlobalAveragePool.h:61:54: error: cannot compile this
      aggregate expression yet
    eResult = eigenTensor.mean(Eigen::array<int, 1>({2}));

Workarounds

• Use cMake.
  • By doing this we will be supporting Windows natively (without docker).
• Change the aggregate expression so that our compilation has backward compatiability.
  • By doing this we will be supporting Mac OS natively (without docker).

Solution

Implement both the above mentioned workarounds, to fully close this issue!