message: construction_worker: changed c++17 to c++1z
diff: @@ -256,7 +256,7 @@ matrix:
  compiler: clang
  env:
  - COMPILER=clang++-4.0
  - - CXXFLAGS=-std=c++17
  + - CXXFLAGS=-std=c++1z
  addons:
  apt:
  sources: ['ubuntu-toolchain-r-test', 'llvm-toolchain-trusty-4.0']
  